Science topic

Gene Regulation - Science topic

Regulation of gene expression (or gene regulation) includes the processes that cells and viruses use to regulate the way that the information in genes is turned into gene products. Although a functional gene product can be an RNA, the majority of known mechanisms regulate protein coding genes. Any step of the gene's expression may be modulated, from DNA-RNA transcription to the post-translational modification of a protein.
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I have been trying to find a publication that used CUT&RUN (Cleavage Under Targets and Release Using Nuclease) to study gene regulation in bacteria, but have not found it yet... am I just bad at googling/searching Pubmed or it has never been done in bacteria? In that case, is it just because it is a newer technology or there's something that I am not realizing? I have never done CUT&RUN myself but am trying to decide between CUT&RUN vs. ChIP approaches to study gene regulation in bacteria. Thanks.
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After further reading, my understand is that the issue relies on the isolation of fragmented/cut DNA, as in CUT&RUN the long DNA is trapped in the nuclei bound to ConA beads... could a CUT&RUN expert confirm that?
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Most recently, we found the mRNA expressions of JUN,JUNB,FOSL1,ATF were changed when we overexpressed a gene. So ,We would like to know the potential regulatory mechanisms.
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Dear Prof. Pingfu Hou
The AP-1 activity is controlled by the Mitogen Activated Protein Kinases (MAPK), a family of enzymes conserved among eukaryotes that regulate cellular activities in response to numerous environmental signals such as oncogenes, cytokines and growth factors. These signals result in activation of the MAPK pathway via a cascade of phosphorylation events on serine/threonine residues of distinct target proteins, peaking in the activation of the extracellular signal-regulated kinase (ERK), the c-Jun N-terminal kinase (JNK) and the p38 kinase.
The ERKs can activate JunB transcription by activating Ets-1, an ETS-domain transcription factor that augments the expression of Fos and Jun family members (e.g., JunB) through direct binding on the respective gene promoter.
The JNKs phosphorylate cJun at the transactivation domain (ser63, ser73) and ATF-2 within its N-terminal activation domain (Thr63, Thr71), and thus potentiate the transactivation capacity of these AP-1 members.
ATF-2 is also found to be a substrate for p38 kinase, the third member of the MAPK, through phosphorylation at Thr69 and Thr71, which have important implications for its activation.
You may want to refer to the article attached below for more information.
Regards,
Malcolm Nobre
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For my doctoral thesis I would like to carry out a gene expression analysis in the plant Melissa officinalis. For this purpose, I will examine various genotypes that are located in a field that is 60 kilometers away from my laboratory. My idea is to harvest the plant with the stem, store it in the dark and after an hour's journey, mortar the leaves of the plant in liquid nitrogen and store them at -80°C. It is not possible to carry a nitrogen tank in the field during harvest.
I am concerned about gene regulation in the plant triggered by harvesting. Has anyone had experience with gene expression patterns due to plant harvesting? How strong is the gene regulation, and would this lead to a complete shift in the original 'gene pattern'?
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Hi Manuela
expression of stress genes can be seen by this way, but one hour at room temperature even in the dark will conduct to most degradation of DNA and RNA. in addition to what you decided to do, I would add some storage in dry ice in an icebox for the travel.
best regards
fred
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I plan to use the kit from life technologies using CRISPR nuclease vector kit.
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Dear Colleague,
Identifying target sequences along with Protospacer Adjacent Motif (PAM) sites for CRISPR/Cas9-mediated genome editing involves a series of strategic steps. The CRISPR/Cas9 system requires the design of a guide RNA (gRNA) that is complementary to the target DNA sequence, adjacent to a PAM site, which is essential for Cas9 nuclease binding and DNA cleavage. Here is a methodical approach to identify suitable target sequences for your gene of interest:
  1. Understand PAM Requirements:First, familiarize yourself with the PAM sequence required by the Cas9 nuclease you plan to use. For Streptococcus pyogenes Cas9 (SpCas9), the most commonly used variant, the PAM sequence is NGG, where N can be any nucleotide.
  2. Select Your Gene of Interest:Identify the genomic region of your gene of interest where you aim to induce a modification. Consider whether you intend to knock out the gene function (targeting the coding sequence) or modulate its expression (targeting regulatory regions).
  3. Use Bioinformatics Tools:Leverage online bioinformatics tools designed for CRISPR target and gRNA design, such as CRISPOR, CHOPCHOP, or Benchling's CRISPR tool. These platforms allow you to input your gene of interest and will automatically identify potential target sequences adjacent to PAM sites, considering factors like off-target potential, efficiency, and specificity.
  4. Evaluate Off-Target Risks:A critical aspect of target sequence selection is evaluating the potential for off-target effects. The tools mentioned above typically provide scores or metrics indicating the likelihood of gRNA binding to unintended genomic locations. Select gRNAs with minimal off-target potential to ensure specificity.
  5. Check for GC Content and Secondary Structures:Ideal gRNA sequences generally have a GC content between 40% and 80% and lack significant secondary structures that could impede Cas9 binding. These parameters are often considered by automated design tools but should be reviewed manually if necessary.
  6. Experimental Validation:After selecting your target sequences and designing gRNAs, empirical validation is crucial. Clone your gRNA into an appropriate vector, introduce it into your target cells along with the Cas9 nuclease, and assess the efficiency of target gene editing using techniques such as T7 endonuclease I assay, Surveyor assay, or sequencing.
  7. Consider Ethical and Safety Guidelines:When working with CRISPR/Cas9 technology, it's essential to adhere to ethical guidelines and safety regulations, especially if your work involves human or animal subjects.
By following these steps, you can identify appropriate target sequences with PAM sites for CRISPR/Cas9-mediated gene editing. This technology offers unparalleled precision in genome engineering, but its success hinges on careful target selection, design, and validation.
Best regards.
Take a look at this protocol list; it could assist in understanding and solving the problem.
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2024 3rd International Conference on Biomedical and Intelligent Systems (IC-BIS 2024) will be held from April 26 to 28, 2024, in Nanchang, China.
It is a comprehensive conference which focuses on Biomedical Engineering and Artificial Intelligent Systems. The main objective of IC-BIS 2024 is to address and deliberate on the latest technical status and recent trends in the research and applications of Biomedical Engineering and Bioinformatics. IC-BIS 2024 provides an opportunity for the scientists, engineers, industrialists, scholars and other professionals from all over the world to interact and exchange their new ideas and research outcomes in related fields and develop possible chances for future collaboration. The conference also aims at motivating the next generation of researchers to promote their interests in Biomedical Engineering and Artificial Intelligent Systems.
Important Dates:
Registration Deadline: March 26, 2024
Final Paper Submission Date: April 22, 2024
Conference Dates: April 26-28, 2024
---Call For Papers---
The topics of interest for submission include, but are not limited to:
- Biomedical Signal Processing and Medical Information
· Biomedical signal processing
· Medical big data and machine learning
· Application of artificial intelligent for biomedical signal processing
......
- Bioinformatics & Intelligent Computing
· Algorithms and Software Tools
· Algorithms, models, software, and tools in Bioinformatics
· Biostatistics and Stochastic Models
......
- Gene regulation, expression, identification and network
·High-performance computational systems biology and parallel implementations
· Image Analysis
· Inference from high-throughput experimental data
......
For More Details please visit:
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Veryy nice I interesting
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We want to use some natural oily material as the nutrient for HeLa cells. According to the Insoluble material in medium, if we want to treat HeLa cells with oily material in order to study the effects of the oil in the growth and division also in the transcription of treated HeLa cells, what is the best method and has somebody done projects like this?
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Dissolve the oil using dmso and test the efficacy, a dmso alone control can be maintained to ensure the undesirable effects of dmso. Usually less than 0.05% dmso is effective. Best wishes.
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Hello,
I am designing a plasmid with an SV40 promoter-driven antibiotic resistance. Does expression from an SV40 promoter require a TATA box upstream of the transcription start site? The original vector had a TATA box at -30, however this is lost in my cloning strategy. With my current plan, the transcription start site is just 8bp from the end of the SV40 promoter. Will this allow for expression, or is a TATA box needed?
Thanks!
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The SV40 (Simian virus 40) promoter is a strong viral promoter commonly used for driving gene expression in various experimental systems. While the presence of a TATA box upstream of the transcription start site is a common feature in many promoters, the SV40 promoter is unique in that it lacks a canonical TATA box.
The SV40 promoter utilizes an alternative mechanism for transcription initiation called the "TATA-less" promoter. Instead of relying on a TATA box, it utilizes other elements and transcription factors to initiate transcription. The absence of a TATA box in the SV40 promoter does not necessarily impair its ability to drive gene expression.
Therefore, in your current cloning strategy where the transcription start site is located just 8bp from the end of the SV40 promoter, it is likely that the expression can still occur without the presence of a TATA box. The SV40 promoter contains other regulatory elements and transcription factor binding sites that can facilitate transcription initiation.
However, it's worth noting that the exact transcriptional activity may depend on the specific context and the downstream sequence elements present in your plasmid. Experimental verification, such as measuring the expression levels of your gene of interest, can help confirm the functionality of the modified SV40 promoter in your specific system.
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I'd like to know that what are the different ways to know/identify whether a particular Gene is expressed or not ?
Few points from my side are :
1) identifying it's corresponding m-RNA transcripts level.
2) identifying the protein that was produced by the expression of that particular Gene.
Any other points ?
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Hi,
You can do qPCR to check the expression of the target genes.
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When staining with hematoxylin and eosin of a muscle biopsy from a patient with T341P desminopathy, we observe accumulations of inclusions similar to nuclei (arrows in figures 1 and 2, x280). And outside of these accumulations - adipose tissue, which used to be muscle tissue. There are no such massive accumulations of inclusions in adjacent muscle fibers. We assume that clusters of inclusions are not nuclei? Figure 2 is the inverted figure 1.
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Dear Geir Bjorklund, Duc M. Hoang, John Hildyard, thank you very much for your answers and recommendations!
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I am looking to model how expression of a target gene from a state of dysfunction (i.e., knockout; CRISPR-Cas9 induced) to overexpression may influence aspects of neuronal functioning/morphology using patient-derived hiPSCs. The gene itself is associated with several neurodevelopmental phenotypes, so I would like to measure the effects from the iPS cell state -> NPCs -> neuronal state to try and capture whether the degree of expression influences the ability of the cells to mature into neurons.
The target gene itself is quite large (>195kb), so it was suggested to me to apply CRISPRa to achieve overexpression as this makes use of endogenous transcriptional machinery to upregulate the target. However, I have not come across any published articles where (1) gene upregulation is initiated prior to and sustained throughout the differentiation process (i.e., the CRISPRa system is introduced once the cells are at the desired cellular phenotype), or (2) upregulation is maintained over an extended time course. The latter may be necessary to allow me to measure functional outputs of interest. I am thinking an inducible system approach would be useful here, but am open to suggestions!
I am very green in this area of research, and CRISPRa has not been previously attempted in my lab, so would immensely appreciate any advice/recommendations on how I might approach this!
Thanks :)
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Thank you for your suggestion Shambhabi Chatterjee!
It may be the case that I cam unable to effectively upregulate the target gene expression during the differentiation process due to to a reduction doxycycline response.
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A patient with desminopathy survived Covid-19 six months ago without pneumonia, but with a temporary loss of smell and taste. After Covid-19, we note an accelerated progression of desminopathy, penetration accelerates, new muscles are quickly involved in the pathological process, muscle mass decreases, and heart function worsens. Perhaps the infection or its consequences are somehow connected with the mechanism of progression of desminopathy?
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To save life in desminopathy, can the body purposefully reduce muscle mass, for example, due to decreased heart function or for another reason?
It is known that when hypothermia, the body sacrifices limbs for survival. Is it possible with desminopathy a similar phenomenon?
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Dear Mozhgan Norouzi, thank you very much for your reply!
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Hi, Iinserted gene of Reverse transcriptase into pPLc245 plazmid. If I'm right, this plazmid doesn't code cI857 represor. For expression od reverse transcriptase from this plasmid I used E. coli DH10B. RT was expressed after increase of cultivation temperature to 37 °C. Before this thermo induction I cultivated E. coli DH10B with pPLc245 at 28 °C. But at this temperature RT was not expressed. Why is this possible? Is E. coli DH10B coding cI represor or pPLc245 could contain gene for this represor?
Thank you for all responses.
Bohuš
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If your plasmid really is pPLc245 (and not some derivative of it) then it should not carry the lambda repressor gene and you should get constitutive expression at any temperature. So I can't really explain your result unless RT does not fold properly to have activity at RT or 28.
I'm actually a bit surprised this worked at all for you though, generally plasmids with superstrong promoters like lambda pL are not very stable under conditions where there is no repressor.
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Hi all,
I want to know the kinetics of a transcriptomic response to infection. I am interested in the earliest time points, how minutes does it take a cell to activate a gene upon infection?
Thank you for your insights
Julien
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The cascade leading to the transcriptional factor activation is short, in the case of the canonical ones (NFkB, IMD). The accumulation of the transcripts is another subject matter. The structure of the promoters of AMPs suggest non immune related transcription factors are likely to bind and interfere with the specific transcription. HIF binding site, for instance, is frequently found nearby these genes, suggesting a potential hindrance upon redox stress.
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I need to identify and compare TFBSs in a number of sequences. I've used Transfac with the Match program (http://gene-regulation.com/) before but it seems that the website has been having issues lately. Are there other programs that can accomplish similar tasks? Ideally I'm looking for something browser based, but I can work with command line if that's the next best thing.
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Dear Jacob
Kindly read following review article in which they mentioned few online tools other than TRANSFAC
Best regards
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I am using DAVID (https://david.ncifcrf.gov/home.jsp) to cluster some genes I found upregulated in my RNAseq data. I am just using the official gene symbol without any quantitative data. However, the KEGG pathway results are giving me p-values which are extremely high. It does not make any sense to me. How the p-value can be calculated without any number? Can the p-value be significant?
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Functional enrichments are based on statistical tests made with CATEGORICAL VARIABLES (which differ from numerical ones that we use, for instance, in a t-test). This means that your test will find out wether the genes of a particular pathway or biological process are significant, given the number of the genes/proteins that you put as input, the list of genes/proteins belonging to that pathway/process and a specific background (that could be the entire transcriptome, proteome, or the total list of genes/proteins of your experiment). Thus, you should not be surprised to get a p-value.
If you want to rank your genes/proteins, giving priority to genes that have a higher or lower fold change for your enrichment analysis, you could use GSEA from Broad Institute https://www.gsea-msigdb.org/gsea/index.jsp
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I'm trying to purify a natively expressed protein from a large operon, native expression levels are very low, does anyone have any experience with changing the innate promoter with let's say an inducible one? Is it possible? I'm trying to find any literature on that, but don't see much.
I'd appreciate any help :)
(heterologous expression from a vector is not an option)
All the best!
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alright then you can use lamda red to take the regulatory region of a plasmid for induction and recombine it instead of the native promoter. You can for example use pQE-5 as template (https://www.snapgene.com/resources/plasmid-files/?set=qiagen_vectors&plasmid=pQE-5) you add homology arms that are 50bp start from the atg codon from your target locus and extend 50bp and do the same with the other homology arm (I cannot advice where to stop since I do not know the locus you are targeting therefore you will have to use your own judgement for that). The pQE-5 plasmid has an IPTG regulated t5 promoter hence no need for a t7 strain and it also has an amp maker close to the promoter add your homology to this fragment allows to easily identify the recombinants that took up the promoter + amp (hence the wt promoter has been switched). Of course you can use whatever plasmid you want as template depending on the system you want to incorporate just make sure you gel purify your fragment before electroporation otherwise you will end you with the plasmid itself rather than the promoter swapped region.
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Is there any database that can provide me with information on how a particular gene is regulated (for example, names of transcription factors)
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awo! great, thanks
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I have analysed some bioinformatically important information relevant to gene regulation. I want to publish it.
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Hi,
Pharmacognosy Magazine, Bioinformation, Advances in Bioinformatics, Current Drug Discovery Technologies, Chemistry Research Journal, In silico Pharmacology, Medical Hypotheses, Journal of Biomolecular Structure and Dynamics.
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I would like to create a biosensor in which gene1 produces the cellular receptors for a ligand. Upon the binding of this ligand I would like the transcription of gene2 to be activated. This can be done with a histidine kinase receptor.
Mostly, I want to know if this can be done with 1 vector and not 2. If yes, then how can I promote the expression of gene1 under all conditions and not the gene2.
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Great! Hope you figured out how to get one induce the other. Good luck.
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Hi,
I am working on molecular validation of co-expressed genes in Rice under moisture stress.
I have a list of genes that are co-expressed in three rice varieties, under a particular set of physiological conditions. How do I plot/draw a gene regulation network ?
What else data do I need to do the same? Is there a Bioinformatics tool?
Thank you
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We recently identified a novel transcriptional isoform of a gene in brain. It's endogenous expression is very low compared to the annotated one. Exon 1 of the gene is missing, and a portion of a long terminal repeat (33bp) spliced into Exon 2. Thus, the first ATG for this new isoform is found in Exon 6 due to the loss of Exon 1. my question is: 1. is the new isoform translated into protein? 2. if not, how can we test it is a non-coding RNA? 3. If it is translated, how can we test the protein it makes.
Thank you very much!
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northern blot analysis
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Hi everyone,
With the weird social isolation issues we are all facing i am hoping to find a few people to start some discussions.
If we can't attend conferences, then why not try some other means of trading some knowledge to help get our experiments moving again when we are back in the lab (if you find yourself in isolation that is).
I have a project at the moment looking at epithelial mesenchymal transition in CF airways. I am a little bit stuck at the moment after developing a lineage tracing vector, which possibly stems from not enough fore thought regarding E and N-Cadherin gene regulation.
If anyone has any experience with EMT, E or N-Cadherin gene regulation, or lineage tracing vectors/methods, it would be great to chat to you.
Happy to discuss via email and or zoom
Kind regards,
Nathan
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Legitemedly, sure it would not be expressed, because as you knock-out the first exon probably by frameshift, all you get is residual of proteins which are not functional and decays swift. Sometimes, however, there are secondary starting codons in different part of exons which can produce sort of pseudogenes but rearly functional.
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I am looking for putative transcription factors binding sites (which I know the sequences of) on some promoters (which I also know the sequences). What I want is a software where I can upload my promoter, the consensus sequence of one TF, and it tells me how many of putative binding sites (with a certain degree of liberty) can be found on my promoter sequence.
(FYI, I work with budding yeast)
Thanks for you help
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Nice Topic , Following
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I am sure if the binding site of a microRNA can be implicated on a gene or mRNA there one can conclude about the mechanism of action and in a cancer case, its parthenogenesis.
Is the binding on both 3' and 5' end of mRNA, just 3' UTR or other coding region?
Recall also that they have multiple targets, if this microRNA binds to more than one sites, can can one implicate the specific one responsible for regulation?
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Good Answer Satyajeet Salunkhe
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Suppose i have a DNA sequence and i want to find transcription strat site, CDS, poly A signal etc., which software will be useful to find this out?
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#GlimmerHMM is a new gene finder based on a Generalized Hidden Markov Model (GHMM). It actually helps you to annotate the draft genome by running a few simple commands.
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The attached image shows chromatograms from the same FAME sample run three times on our GC-MS. As seen, additional peaks show up if running the sample several times. From the MS spectra the additional peaks seem to be plasticizers. If I heat the column to max for 30 min and then rerun the sample the peaks are gone. The additional peaks elute at approximately the same in all samples. I have tried changing septum, liner, injector needle, needle wash whiteout any improvements. Any suggestion how to lose these peaks? Thanks in advance.
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What is m/z for plasticizers peaks?
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Hi all,
I am working on the interaction between C. elegans and the nematode-trapping fungus. Now I found a gene in C .elegans called epc-1 which will have the phenotype I want when it was deleted. It is to contribute to histone acetyltransferase activity. Now I am wondering how to find the genes regulated by it.
Could anyone give me some suggestions? I will very much appreciate it.
Thanks,
HanWen
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Hi Hanwen,
There are a number of websites that compile gene information, but the biggest determinant for you in choosing a website is probably the one with the most relevant and detailed information for your organism. Some general websites include Uniprot and NCBI.
If you have a set of genes that you want to identify pathways, GO-term searches can be helpful and can be acquired from websites like http://amigo.geneontology.org/amigo.
In the end, I think the best source of information would be searching the primary literature or reviews that cover your gene of interest. You can find literature in Web of Science, Pubmed, or even Google Scholar.
If your gene has never been studied before, there still are ways to get some hypotheses on relevant pathways, namely to search for sequence homologues of your gene in other organisms where there may be more information (websites such as BLAST or https://www.flyrnai.org/cgi-bin/DRSC_orthologs.pl).
Thanks,
Barry
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I have got a promoter region which is size about 1000bp from human genome. I'm trying to find cis acting elements corresponds for gene regulation in multiple myeloma. What are the freely available methods for this?
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In brief,
1. Use the genomic sequence to find out potential transcription factor binding site(s) using the TRANSFAC program (or any other free program);
2. Generate a reporter construct with the promoter sequence to be tested;
3. Use potential sequence(s) for a candidate TF to perform binding assays using the labelled cis-sequence;
4. Mutate the potential TF binding site(s) in the reporter to demonstrate the specificity of binding;
5. Perform ChIP assays to demonstrate binding of a TF to cis-sequence in vivo (in cells).
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I'd like to purchase some custom DNA microarrays, circa 100K spot density and 30mers in length. Would anyone be able to recommend a company?
thanks
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You can visit this website http://www.sciomics.de/services/microarray-printing. Hope this helps
Regards
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In a patient with hereditary desminopathy (Thr341Pro DES mutation in the heterozygous state), a significant loss of muscle mass is observed after a night's sleep, with its replacement by adipose tissue. How to reduce muscle loss during sleep?
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Dear Ali Javadmanesh, Adrian Fierl, Abdulnabi Abdullamer Matruod, thank you very much for your answers!
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Hi,
i am currently looking for an experiment alternative to southern blot. I heard that pcr based assays give results quickly ( let's say within few hours). I want to perform sybr green relied pcr to detect copy number of my interested gene in the human genome like in southern blot. however, I couldn't find a proper protocol. If you address a protocol or share your experience, I will appreciate.
Thanks.
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Agree with the author above. If there are multiple copies of GOI scattered around genome, Southern blot may not resolve all of them, and qPCR may also be inconclusive. You may need to do NGS using long read platform to convulsively determine the copy number. qPCR is handy for an estimate.
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I need a suggession for a good RNA isolation protocol from Serum/Plasma. Looking for any kit name of any modification of protocol etc
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Hi Andrea,
RNA found in both plasma and serum is normally fragmented RNA or small RNA , mainly miRNA, and is either bound to proteins or contained inside extracellular vesicles. If your target is to purify mRNA from plasma/serum then you have to be aware that this mRNA may not be the full length, original RNA, that you may be getting when isolating RNA from whole blood.
I personally recommend for you using one of Norgen's Plasma/Serum RNA Purification kits ( https://norgenbiotek.com/sites/default/files/resources/Plasma-Serum-RNA-Purification-Kit-PI55000-5.pdf). These kits covers a sample volume range from 50ul up to 5mL without using any phenol or carrier RNA. Unlike other purification kits, Norgen's kits uses Silicon carbide as its separating matrix instead of silica. Some literature has mentioned that silica-based technology with/without phenol has a bias towards binding large RNA sizes as well as a bias towards binding RNA with sequences containing high GC contents whereas Norgen's Silicon carbide doesn't have such a bias.
For the isolation of RNA from blood, this should be a straight forward isolation but you have to use a different isolation method for this. I also recommend using Norgen's Total RNA Purificiation kit (Cat. 17200) for this.
When isolating RNA from plasma/serum you should be expecting low RNA amounts (normally in the picogram range) therefore you can't quantify you plasma/serum RNA using conventional methods such as regular spectrometer or Nanodrop since they are not sensitive enough to quantify such low RNA amounts. I recommend using Agilent Bioanalyzer RNA Pico Chip for quantifying plasma/serum RNA. Also don't relay on the RIN values from the bioanalyzer chips cause it will be low and won;t reflect the quality of the purified RNA. RIN values are calculated based on the ratio of the 28S rRNA and the 18S rRNA and since plasma/serum doesn't have cells therefore the purified RNA won't have these two bands which will lead to a very low RIN value. The best way to evaluate the quality of the purified RNA is to amplify a highly abundant small RNA target such as the 5s rRNA or to amplify a highly abundant miRNA such as miR-21. I believe that what Norgen does when performing small RNA sequencing services. https://norgenbiotek.com/services/small-rna-and-microrna-next-gen-sequencing
Sorry for the long message but I just want to give you some detailed information so you don't face any issues through out you project.
I hope this answered all of your concerns.
Best Regards and Good luck.
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I want to check whether any response element is present for a particular set of transcription factors on my gene of interest. I have already found EPD (http://epd.epfl.ch/) for promoter sequence and motif search and JASPAR (http://jaspar.genereg.net/) for response sequences. But the problem is, I am not able to merge those information.
The problem with EPD is, many gene promoters are not available. Even if they are available and I find transcription factor motifs on my gene of interest, there is no way to see them as sequence and annotate it.
So, if someone knows any software/ database/ technique for this purpose, it will be immensely helpful for me.
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Biswajit Biswas I'd also recommend looking at the various ENCODE tracks. For example: https://genome.ucsc.edu/cgi-bin/hgTrackUi?hgsid=725021383_RGLKNnOIuYWhC8gnLaWXEWCGidL3&c=chr21&g=wgEncodeTfBindingSuper gives you actual TFBS data from experiments. You can click on the names of any track to see detailed information. Keep clicking through the links on the subsequent pages to turn on/off specific TFs and cell lines.
For mouse, there are several experimental TFBS tracks in the mm9 assembly under "Expression and Regulation".
As Frederic Lepretre pointed out, the table browser option will allow you to pull the associated information for your genes/regions of interest. I'd also be happy to help further by private message, if you need it.
Good luck,
Ryan
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Predicted G2-M phase cell cycle defect mutant change ploidy distribution , but most of the cell cycle progression gene up-regulate in mutant background.
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Thank you, Mr. Nashaat Ghalib, for your interest. I found the opposite expression pattern of some important downstream gene.
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There are specific gene for specific expression. But if any one gene regulated ( up or down ) then other gene will also effected for their regulation or not?Though they may or may not be interlinked.
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Thank you for your suggestion.
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I have very limited resources in my lab and very narrow budget. I used to use the red blood lysis solution, but I'm now trying to find a new protocol. Can anyone help?
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How I can isolate WBC from whole blood ?
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When we have a positive regulation the control is tight, so we have low background expression under non-induced conditions.
Negative regulation can not be fully controlled, but as far as I understand it is more popular than positive regulation.
Why?
Are there any other important features of these two types of regulations?
Thank you in advance!
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I think many of the respondents are mixing up the difference between positive and negative regulation, which is defined as the behavior of the regulatory protein, which is not the same as a inducible or co-repressible system. For example in E. coli both the arabinose operon and the lactose operon are inducible by the sugar, but lac operon is primarily controlled by a repressor and hence negative regulation whereas ara operon is positively regulated by a transcriptional activator (I realize that is an oversimplification for both but primarily correct).
For controlling gene expression and inducible system is normally easier to regulate because you just need to add the small molecule inducer to turn on gene expression, whereas in a co-repressible system you would need to remove the co-repressor (frequently an amino acid or something similar). So from that context inducible is much easier.
Whereas the difference between a negatively regulated vs a positively regulated system is about the behavior of the regulatory protein. The problem with a negatively regulated system is that for controlling a multi copy plasmid you need to have excess repressor present, and usually a single copy of the repressor gene on the chromosome does not suffice. So often negatively regulated promoters are not as tightly regulated and may have substantial basal expression. Whereas for positive regulation you don't have the same difficulty and the basal uninduced expression levels are usually lower (more tightly regulated).
As to why negative regulation is more common in plasmid systems, I think it primarily is historical. The lac operon was extremely well studied and understood in E. coli at the time many cloning and expression plasmids were being developed and it has just stayed with us.
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To assess whether expression of the gene of our interest is associated with mutant status of p53 we have treated FaDu cells( mut-p53) with CP-31398, a Known p53 stabilizer, that restore a wild-type DNA-binding conformation of mutant p53. we check the expression by TaqMan based q-PCR, and got expected result, but when we treated the Fadu cells with Pifithrin-α( an inhibitor of p53 ) we again got the same trend( in both cases RQ is 0.2 & 0.4 respectively), while we are expecting No change or Induction. According to the publication: Cancer Biol Ther. 2002 Jan-Feb;1(1):47-55, FaDu expressed only 50% of the normal level of p53 mRNA, either because only one allele was present (A431), or because only one of the two alleles was transcribed. What could be the possible reason of same trend of gene expression after the exposure of CP-31398 & Pifithrin-α in Fadu Cells?
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May the the molecule of your interest which you are working is simply not involved in cascade. The result can be interpreted as it has no role in particular pathway or may be any other signaling deivn the proces. Thanks
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Dear all,
I am eager to know your opinions about site-specific expression of secondary metabolite genes in plants. Which one is more involved: epigenetic regulation, transcription factor-mediated gene regulation or post-transcriptional gene regulations?
P.S: It is clear that all mentioned items (and other mechanisms) are involved, but my question is which one is more engaged, specifically for secondary metabolite differential biosynthesis?
Many thanks for all your consultations,
Ahmad
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I'm trying to look at the induction of candidate genes involved in plant defence when I block the signalling pathways related to JAs and ethylene and apply different stresses. For ethylene I can use the AVG, an inhibitor of ethylene biosynthesis, but as far as I know, there are no inhibitors of the jasmonate signaling pathway. Do you have any info about it?
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I need to find an over-expressed thyroid hormone receptors hepatic cell line 
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good question
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Dear all,
Recently I am performing RT-PCRs and Western blots of a mammalian cell line in which I overexpressed two vectors (wild-type and mutated) of equal promoter and sequence length. However, in both RT-PCR and Western blot I observed very different expression levels between both vectors, despite always transfecting the cells with the same amount of DNA. Could these results be acceptable for publication? Could I assume that the mutation is affecting the gene regulation of its vector in a different way? Or should I normalize this effect in some way in order to explore changes caused in other genes/proteins?
Thank you
Jaime
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Hi there,
First of all you have to repeat the experiment in order to be able to validate the hypothesis that mutation has a significant effect at RNA/protein levels. If you want to normalize the data you definitely need an internal control (from a housekeeping gene both for RNA and protein levels).
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When I give a list of genes regulated by my protein of interest as input in GSEA MSigDB, does the output of C3 TFT mean that my set of genes regulate these Transcription factors?
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If I may complete the previous answers: GSEA calculate enrichment of a set of genes over the entire genome. If you get hits in C3 TFT, it means that your set of genes are probable targets of the transcription factors that are indicated by GSEA. Therefore if what you call "hits" are the C3 TFT results, it's understandable that they are not (all) in your gene subset. However, if you look at the genes which make the C3 TFT result significant, they should all be a subset of your gene list. Now, if your set of genes is regulated by a protein of interest and you get indication of putative regulation by some TF, it might be that your protein of interest is another TF working in dimer or a transcriptional cofactor and it may be worth investigating.
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Dr. Magnus Nordborg recently pointed out in a presentation that is no evidence that methylation is involved in either development or adaptation and there is still little evidence of the involvement with gene regulation.
Also, the paper "Epigenomic Diversity in a Global Collection of Arabidopsis thaliana Accessions" (Kawakatsu et al. 2016) showed methylation in Arabidopsis strongly correlated with geography and climate of origin.
It seems that environment controls both methylation and gene expression but there is not necessarily a cause-effect relationship between these two.
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I support the comments of MR Schaefer and I can contribute that epigenetic changes also interfere in the behavior of transgenic plants in field conditions.
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Gene regulation and environment are quite related with each other thats why the circadian rhythm is maintained but what are the exact factor for that specific gene expression and the molecular mechanism behind detecting the environmental changes by the human body?
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Ok sir.
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We are using lipofectamine for transfecting synthetic miRNA mimics for the miRNA functional analyses and miRNA target site validation experiments that we are developing with human cancer cell lines. However I would like to know if in your experience those experiments work as well with jet-PEY or similar reagents, which seems to be more cost effective. Thank you, Inma
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It all depends on the cell line, and the transfection reagent for it as well. Given the similarities between miRNA and siRNA, if you find reagents that work well for siRNA delivery it's likely they'll work for miRNA delivery as well. See this catalog (https://altogen.com/products-index/) and you'll see that different cell lines have different efficiencies, even for optimized reagents. Generics will work, but they won't be stellar. Look through previous studies to see what reagents they used for given cell lines, and you should be set for getting the empirical values for efficiency as well.
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We will performed ChIp and reporter gene assays to functional validate rSNPs identified within breast cancer-relevant regulatory regions. Which breast cancer line is most suitable for this study? or alternatively, how to select it among the available breast cancer lines such as MCF10 MCF7 HCC1954.
Thank you
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Dear Laura,
You don't give details about which association with breast cancer you are talking about but I assume it is association with risk (not outcomes) of breast cancer.
In this case (examining risk), the assumption is that this candidate SNPs would have its effects driving risk in a "normal cell" (the cell of origin of the tumor being studied) and therefore your best bet is to use a immortalized 'normal' MCF10A.
Sometimes 'normal' cells are not available or suffer from technical limitations (low transfection efficiency, or clumping during FACS analysis, for example). In this case, you could resort to cancer cell lines - understanding this is the 'next best model'.
If you decide to use cancer cells make sure you try to use a line that is representative of the tumor subtype associated with the SNP. Sometimes, a SNP is associated with risk of ER-negative breast cancer only and it would not be wise to use MCF7 or other ER-positive cell lines. You should be able to justify your choice of cell lines in light of the question you are asking.
Good luck,
alvaro
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Regulation of gene expression operates at different levels. If you are working on laboratory animals which have a problem with accumulation of a certain protein earlier than the stage when the organisms need it, how would you apply the concept of gene regulation to them? Assume that you have maximal power, capability and all the equipment needed.
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This is a very imprecise question. Is this specific for a strain of animals? Is it genetic and heritable? Does it cause a phenotype that is deterimental to fitness? Lot of genes are expresed in cells that may be superficial or unnecessary, but if they cause no harm then the cell has no reason to suppress expression. When you say earlier, do you mean in embryonic development? If so then the cells are likley to see a signal prematurely. They may have increased sensitivity to a peptide or morphogen, perhaps due to a variant in the receptor. Or, they may be missing a repressor that acts to inhibit expression early but is then switched off later. There are many models for how this could happen.
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methylation is un important process for gene regulation.
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Methylation is a very location-specific mechanism for gene repression, such that hyper-methylation of the gene promoter is primarily linked to reduced transcriptional activity.
In the context of adolescent diseases, imprinting disorders such as Angelman and Prader-Willi syndromes are classical examples of abberent imprinting disorders:
If interested in somatic diseases associated with DNA hypermethylation, the above mention of cancer is a great example. Specifically for adolescents, osteosarcoma and various leukemias (e.g. Acute Myelogenous Leukemia, AML) are malignancies affective younger adults:
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Nuclear extraction of bean tissue
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Hello guys, '
Is it a must to add PMSF ? I only have protease/phosphates inhibitor cocktail ?
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Many articles have used cloning method for understanding gene regulation. what other methods can be used to know the expression of common promotor in different gene regulation.
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You can insert a fragment of your promoter of interest in some plasmid, (for example, pGL3 Basic Vector) conjugated to a luciferase gene (reporter gene). Then you could create mutations in that recombinant plasmid to evaluate how the function of the promoter is affected. I did a similar approach using pGL3 Basic Vector from promega and I created different mutations using Q5® Site-Directed Mutagenesis Kit from NEB. At the end, you can evaluate the response of luciferase gene using the appropriate equipment. However, you need to consider the type of cells that you will use, the reporter plasmid and the length of the promoter that you want to evaluate.
I hope this helps.
Frances M
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I would like to prepare in silico analysis of role chosen by me transcriptor factor(TF) in the regulation few human gene expression.
Earlier I used the TRED: a Transcriptional Regulatory Element Database to the prediction present of transcriptional regulatory elements (TRE) specific for analyzed transcriptor factor(TF) in the promoters of analyzed genes.
TRED: a Transcriptional Regulatory Element Database (http://rulai.cshl.edu/TRED) was designed as a resource for functional studies and gene regulation studies.
Can you suggest me the free simple online tools to predict the presence of a transcriptional regulatory element (TRE) in the promotor of interested genes?
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Thank you all for your answer!
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I have read contradictory reports.
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Has it really been 5 years since I posted this question? How time flies! I no longer work in this field but thank you anyway.
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Gene regulation network of rice with respect to soil salinity and drought are used by researchers to study the genes and their interplay as these stress conditions lead to reduced production of crop produce.
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PFA
The attached content shall be useful to you.
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Enhancers and target promoters are often found "in contact". Some 'in contact' enhancer-promoter pairs stay dormant, i.e., there is little detectable promoter-driven transcription. But other enhancer-promoter pairs 'in contact' are 'active'. That is, both the enhancer and promoter 'in contact' are actively transcribing, generating eRNAs at the enhancers and mRNAs from the promoter. So, if we look at the 'in contact' enhancer-promoter pairs, they can either both be transcribing, or both not transcribing. My question is, is there any enhancer 'in contact' with a transcribing promoter but is itself not transcribing? That is, only the promoter is active, but the enhancer is not, despite both being in contact with each other? Shall appreciate any insightful answer that provides evidence, e.g., comparative 3C/HiC-RNA-seq data from same cell populations.
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Hi Anil,
Indeed, there may be eRNAs at the enhancer of FT that we overlooked so I cannot guarantee their absence. Several non-coding RNAs, smRNAs, and mRNA datasets did not reveal them though. About the contact of the enhancer with the promoter at the FT locus, there are two papers published (including one from my previous group): Cao et al., 2014 (doi/10.1105/tpc.113.120352) and Liu et al., 2014 (DOI: 10.1038/ncomms5558). In these papers, interactions within the FT locus were investigated using 3C (chromosome conformation capture). Unfortunately, the interactions between the promoter of FT and its upstream region are discordant between the 2 studies. Several factors can explain this discrepancy, including the fact that relatively short distances were probed (less than 5 kb). At the end, I would be really carefull when interpreting 3C data since this method is really tricky (see Jamge et al., 2017, doi.org/10.1186/s13007-017-0251-x).
About other enhancers at FT locus, yes, there are others, but you will have to wait a bit more for our next paper to get out ;)
What do you mean by mutualism exactly?
To get more information about enhancers in plants, I refer you to our review (Weber et al., 2016, doi: 10.1016/j.tplants.2016.07.013).
Best regards,
Johan
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I have a bunch of differentially expressed genes and a long intergenic non-coding RNA, what can do (bioinformatically first) to check the hypothesis that some of these genes may be directly regulated by this linc-RNA?
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Try to see the correlation between the gene expression and the lnc RNA expressions, as a preliminary analysis by writing a simple R script. You could choose the targets for the correlation analysis using online tools suggested by the answer above. There might be good tools which could do all this and much more bioinformatics analysis.
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Hello everyone,
Does anyone know which gene regulate the MyD88 gene expression in the intestinal epithelial cells ? or whether PI3K/AKT regulate the MyD88 expression or not? if MyD88 downregulated in your model, how will you check the signal pathway? Thanks!
Xin
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Hi Xin, You might want to take a look on this webpage:http://www.genecards.org/cgi-bin/carddisp.pl?gene=MYD88 It has info on regulatory elements from different sources:"...This subsection describes genomic regulatory elements related to the gene from GeneHancer. GeneHancer is a database of genome-wide enhancer-to-gene associations, embedded in GeneCards. Regulatory elements were mined from the following sources:
  1. The ENCODE project. Z-Lab Enhancer-like regions
  2. Ensembl regulatory build
  3. FANTOM5 atlas of active enhancers
  4. VISTA Enhancer Browser enhancers validated by transgenic mouse assays."
It also includes Transcription Factor Binding Sites within enhancers and Gene Targets for Enhancer. I hope is useful, irepan
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For studying the role of these receptors in my gene of interest regulation in liver I need to have these cell lines
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Thanks a lot
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We have a nuclear/cytoplasmic fractionation protocol that works well, but the problem is that the isolated nuclei are EXTREMELY sticky and very difficult to work with.
We want to fix these cells, stain for cell-type specific intracellular markers, and FACS sort for RNA-seq. We can do this routinely with whole cells, but isolated nuclei are totally unmanageable.
All buffers are made with Ca/Mg-free PBS, and supplementation of 5mM EDTA does not help. I have also tried treatment with 50U/ml DNase + 5mM MgCl2 to no avail.
Straining cells through a 70um nylon mesh is off the cards, as the nuclei gloops get stuck on the mesh.
Does anyone have ideas/tips and tricks to deal with this problem?
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Hi there. I am working on unfixed nuclei separation from tissue for chromatin studies. What I found was that sucrose in the buffer is essential for the integarity of nuclei, for it helps to maintain the osmatic pressure. 5%-15% sucrose all helps. Mg++ might be also important for the integarity of nuclei. When I simply use PBS, the nuclei don't look good. The DNA was leaking and thus clump them together.
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Hi there,
It has been a long time that I think about one of the important aspects of miRNA research: how many genes mediate miRNA effects? According to the literature, most if not all of miRNAs exert their effects through modulating tens (or hundreds) of mRNA targets (although in different contexts and cell types). For some miRNAs, a small number of key mRNA targets mediate the effects elicited by the miRNA, but for others, a large(r) set of mRNAs are fine-tuned by the miRNA and it is the collective effects of these minor downregulations which lead to a cellular behavior promoted by the miRNA. However, what I see is that almost all of the journals insist on finding a single target for the miRNA of interest! The situation gets more complicated to me when the miRNA influences several behaviors of a cell at the same time (e.g. survival, differentiation, colony formation, migration), yet the reviewer expects authors to find a 'single' target which probably mediates all these diverse effects. Actually, this rationale does not make sense to me, since I think there should be more than one miRNA targets that are mediating the miRNA effects in different cellular contexts.
I would highly appreciate if you comment on my question and let me know what you think in this regard as well as how we should manage a situation where the reviewer requests you to find a single target but you think (or expect) that there should be several miRNA targets, since I think insisting on finding a single target may result in bias (which is not good science).
Best regards,
Sharif
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Hi Sharif
Excellent question and very interesting reflection.
I suffered the same critics from reviewers. Thinking in a very simplistic way, complex eukaryotic organisms are very redundant. So, they have many ways to do the same things. In consequence it should be very difficult to find a "master" miRNA which will regulate a very important gene or pathway. On the other hand, a multiple and complex effect is expected, involving many miRNAs that are working together. Of course that you can find "master" miRNAs in simple organisms, but in humans this is very difficult.
If you want to find interesting miRNAs in a particular process, I would suggest you to use a complex approach, combining information about target recognition and also about pathways. You can distinguish different categories of targeted mRNAs if you pinpoint them into biochemical pathways. More relevant miRNAs will target "receptors" instead of "effectors".
Of course this is not an easy task.. Analysis of many variables is needed. More relevant miRNAs will be the ones that regulate more targets. On the other hand, the most relevant targets will be those regulated with more miRNAs at the same time.
Take a look at this paper where we did this kind of approach.
Best of luck. Waiting for your feedback.
Paco
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Database may or may not contain gene regulation data of other strains.
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Hello Gaurav, DO you know about this 
Hope that will help you. You can use transcription units data. 
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I did RT-PCRs and got several interested genes.  The thing is I want to know the intracelluar pathways that could lead to these genes regulation.
Is someone familiar with this or could someone provide useful tips about that?
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Hi
there are lot of tools, but what you can do is a look on biogps (http://biogps.org/#goto=welcome) , the reactome (http://www.reactome.org) or DAVID (https://david.ncifcrf.gov) to analyze your lists of genes, just to begin. otherwise, my comments match Heena's ones, you should provide more details to get better answers.
fred
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I observed this in one of my microarray experiments in which the first two gene got upregulated and last gene was downregulated. these three genes belonged to the same operon. Kindly suggest
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If you are sure that these genes are in the operon and can confirm these results using qRT-PCR, then the difference can be due transcriptional attenuation, e. g.  premature termination of transcription. Transcriptional termination is one of the mechanisms to regulate gene expression. 
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Hi,
I have 8 different starch samples from stressed wheat (drought and heat). I want to plan an assay for define differences of amounts for amylose and amylopectin.  I have found one assay kit for it but cannot afford the money (kit is for 100 tests and more than 550€ in Turkey). I was looking for some protocols online for wet lab and found 1 about it “iodine complex”. But couldn’t understand the quantification methods. Do you have any suggestions for it?
Thanks,
Deniz.
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The reaction is pretty straight forward. A potassium iodide solution is used as iodine itself is not very soluble and in aqueous solution s the triiodide ion is formed which binds with the spiral structure of the starch molecule and turn to purple-blue color from brown. This blue-black color can easily be measured using a spectrophotometer usually at 600nm. You can easily construct a standard curve using pure starch samples.
As far as a distinction between amylose and amylopectin is concerned, there are some fairly old but tried and tested protocols available that can be used to separate amylose and amylopectin, or if you know the ratio of the two in wheat samples you can get away with measuring just amylose. Also you may need to do a multi-wavelength study to get more accurate results. It can be a bit time consuming but not at all difficult. And yes your concerns about the kits are not unfounded, their prices can be exorbitant but mostly because they are enzyme based.
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We are getting large deletion, although we expecting only small deletion by NHEJ with Cas9 nickase. Between the two sgRNAs is a 22bp gap. The picked & sequenced clones have deletion up to 100bp. Does anyone have an explanation?
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Double nicking in a 22-bp region can generate, in some cases, a "double stranded break" with free DNA-ends like a true (wild type) Cas9-mediated DSB. These ends are targets for exonucleases removing a lot of nucleotides ending up with a 100-bp deletion. 
Getting these free-ended DNA fragments can be generated due to replication or transcription, both of which are in most cases not easily controlled. 
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Dear all,
I want to knock down one protein by 50% in HCC cell lines. I want to know whether it is possible and how to achieve it?
Thanks sincerely for your answer.
Zhou.
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I agree with Joseph Papamatheakis. If you need to maintain this for any length of time, you would have to make a heterozygous null using genome edits tools such as CRISPR/Cas9.
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 Would like to check in vivo if a gene were interested in is indeed flow-regulated. Collaborators will be co-author on the final publication. Your help is highly appreciated
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no,. it is about Tie2
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Hello all,
I am planning to perform a viability drug screen with Selleckchem bioactive compounds library (~2000 drugs). 
My goal is to find drugs that differentially kill cells with  wt or knockout of my gene of interest. Since the potency of drugs varies widely (nM to >50 uM range of IC50) I wonder what is the best design strategy. I saw that people just use 1 uM and/or 10 uM in primary screens but this would miss the relevant range of many drugs, where I have a chance to see the effect of my gene.
Obviously, doing the screen with more concentrations will decrease the replicates for each (I am thinking to use duplicates since CellTiter-GLo gives very tight replicates).
I would appreciate any input regarding the screen design.
Thanks,
Igor
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We do automated high throughput screening in our facility for Chemical Genomics.  For an initial screen, all compounds are used at 10 uM in DMSO.  If you identify a hit, we then do a dose response curve over a broader range from 1 nM to 100 uM. 
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I'm looking for mRNA markers for general IFN response. Also, can the type I and II interferon responses be identified using mRNA expression of defined marker gene sets by qPCR?
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Dear Kristiina,
mRNA markers for  IFN responses can be very cell/tissue specific.
But you can consider the following "general" interferons:
Interferon-α&β Receptor Ligands: IFNA1, IFNA4, IFNB1.
Cytokine Receptor Ligands: IFNA14, IFNA16, IFNA2, IFNA21, IFNA5, IFNA6, IFNA7, IFNA8, IFNE, IL15.
Interferon Related Genes: IFRD1, IFRD2, IFNL2, IFNL1, IL6.
You can also monitor the general Interferon Receptors:
Interferon-α&β Receptors: IFNAR1, IFNAR2.
Hematopoietin & Interferon-Class Receptors: IL10RB, IL11RA, IL12B, IL13RA1, IL20RA, IL21R, IL22RA2, IFNLR1, IL2RB...(there are few more)
Monitoring the "common" Interferon Regulatory Factors may also be a good idea:
IRF1, IRF2, IRF3, IRF4, IRF5, IRF6...
Usually we  initially test a broad range of mRNA markers to ID those best expressed in the specific cell line/tissue.
Good luck!
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Hi,
I'm purifying a recombinant protein. It's secreted protein. After chromatography procedure, I have some samples of protein:
- Fermentation sample (applied sample): the supernatant from BSM medium (pH 7.1 - 7.3, conductivity: 35 mS/cm, approximately)
- Column flow sample: pH 4.0
- Eluted sample: pH 7.0, NaCl 0.9 M, Tris-HCl 20mM,
I see these three protein samples have three different buffer. I want to measure the amount of protein in these samples by Bradford assay method, but I don't know which buffer should I use to balance. I'm using mQ for this step.
Please give me advice. 
Thanks.
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Hi, in the Bradford assay you have to prepare a standard curve, in particular you have a linear range of the assay for your standard protein, for example BSA, between 1 to 20ug or 20-140 ug. In the standard curve you have to add the ul of lysis buffer in which you resuspended your protein of interest. The same ul of buffer the you add to your blank sample. In your situation, if I understand correctly, the buffers are different (prepared with completely different reagents), so you have to prepare a blank and curve samples for each buffers, in this case 3 curves and 3 blanks (all in duplicates at least). Another way, not properly correct, it would be to prepare only a standard curve, without adding any buffers, only water, and prepare at least 3 different blanks.
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I have mouse tissue expression genes, but I  did not found any database or r package for this purpose ?all for human
kindly answer
second I also have lncrna data what kind of ontology or other bioinformatics analysis I can do (mouse data)
?
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For mouse gene ontology analysis, DAVID tool can be used.
Check this review for bioinformatics tools for lncRNA research
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I used genomatyx to analyze transcription factors in promoters sequences, but now I have many problems to login, so does anyone knows another facility to do this?
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Use JASPAR
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It is known that around 1000 TFs are discovered in human cells (bionumbers website). But the statistics about TF-gene interactions are not clarified enough. The answer to this question is crucial in my simulation project. Anybody who could reply to my question based on scientific references would be appreciated as co-author in the final reports. 
Best Wishes,
Mohieddin Jafari
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I read somwhere (I have to find this reference) that a mammalian cell has 5000-6000 expressed genes.
If the human genome has let's say 30000 genes, then around 1/5th of the genes are active in each cell type. And  around 4/5th of the genes then are repressed. Maybe this gives a starting point for some guesstimation work?
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I am trying to knockdown basal level expression of my target microRNA by transfected Anti-Mir,miRNA Inhibitor, but I didn’t get significant  level of knockdown  result by real time PCR.
Have any one any idea please help me?
Conditions.
·         Cell line-MCF12A (The MCF-12A cell line is a non-tumorigenic epithelial cell line). For cell culture I am using  MEGM, Kit Catalog No. CC-3150 by  Lonza/Clonetics with 100 ng/ml cholera toxin.
·         Name of the transfection reagent- lifofectamin 2000(forward transfection),  RNAiMAX(reverse transfection). Transfection down by according to the thermos fisher scientific. I did also forward and reverse but results is same after 24h and also 48h of incubation.
·         For the RNA isolation, used miRCURY RNA isolation kit(EXICON). For cDNA making, used miRCURY LNA universal RT microRNA PCR/Universal cDNA Synthesis kit(exiqon), for real Time PCR, used miRCURY LNA universal RT microRNA PCR/ExiLENT SYBER Green(exiqon). For endogenous control I used U6. Everything I did according to company protocol.
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Locus specific hydroxymethylation quantification using NEB EpiMark Analysis Kit. Does anyone has a template for data analysis using this kit? I want to use raw ct values for my hydroxymethylation analysis and tried to do qpcr but for some samples I don't see any ct values? I am not sure if my conversion protocol failed or my qPCR is not working well. Any suggestions?
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5hmC levels could be very low and not even detectable with qPCR. Did you use the control DNA (5mC, 5hmC and unmodified)? If those gave the expected results, then did you run a qPCR of your fragment of interest without any restriction enzyme? Was the result positive (do you have enough DNA to start with)? NEB Epimark is based on the same technology / concept (beta-glycosylaytion of 5hmC) than Active Motif Specific Chemical Labelling (SCL) precipitation of 5hmC that can also be used for detection at a single locus, except that NEB doesn't use precipitation but 5hmC sensitive restriction enzymes. As a SCL user, I have also been confronted to very high Ct values (> 38) at some loci which are very poorly enriched in 5hmC. How many cycles of qPCR are you doing? I usually run at least 45 cycles. Good luck !
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Dear all
I am going to produce zebrafish knock-in by CRISPR/Cas method. So I want to know proper concentration of CRISPR/Cas components for knock-in (sgRNA, Donor plasmid, Cas9 mRNA). Does anyone have experience with this?
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