Yumin Mao

Fudan University, Shanghai, Shanghai Shi, China

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Publications (155)347.15 Total impact

  • Article: Cloning, expression and biochemical characterization of a novel, moderately thermostable GDSL family esterase from Geobacillus thermodenitrificans T2.
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    ABSTRACT: A thermostable GDSL family esterase-encoding gene, EstL5, was directly obtained from the genomic DNA of Geobacillus thermodenitrificans T2. Recombinant hexahistidine-tagged EstL5 was overexpressed, purified, and its biochemical properties were partially characterized. EstL5 was observed to be active within the temperature range of 0-80°C, having maximal activity at 60°C. Unlike most other thermostable enzymes, EstL5 displayed 24% of its highest activity at 0°C. EstL5 exhibited a high level of activity within a pH range of 6.0-11.0, showing the highest activity at pH 8.0. EstL5 also retained 100% of its activity after a 12-h incubation at 55°C. Furthermore, this enzyme was observed to be strongly inhibited by 10% (w/v) SDS and 0.1 mM PMSF.
    Journal of Bioscience and Bioengineering 09/2012; · 1.79 Impact Factor
  • Article: Co-evolution analysis on endocrine research
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    ABSTRACT: The rapid growth of different kinds of biological information allows a good opportunity to analyze the co-evolutionary characteristics in endocrine regulatory pathways. Data ranging from kinds of species’ genome, gene sequence, protein structure, and expression profile of different organisms can reveal the inner co-evolutionary relationship of ligands, receptors, and other related molecules. In return, these co-evolutionary characteristics can help us determine uncharacterized ligands and receptors, annotate gene functions, highlight amino acid residues with biochemical significance, and identify regulated genes in the endocrine process. Encouraging examples in this field, although at their starting stage, have emerged. Here we focus on recent progress in endocrine-related co-evolution research from a methodological approach.
    Endocrine 04/2012; 28(2):187-192. · 1.42 Impact Factor
  • Article: Crystal structure of Human ASB9-2 and substrate-recognition of CKB.
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    ABSTRACT: Human ankyrin repeat and suppressor of cytokine signaling box protein 9 (hASB9) is a specific substrate-recognition subunit of an elongin C-cullin-SOCS box E3 ubiquitin ligase complex. It recognizes its substrate, brain type creatine kinase (CKB), using the ankyrin repeat domain; and facilitates the polyubiquitination of CKB to mediate proteasomal degradation through the SOCS box domain. HASB9-2 is an isoform of hASB9 that contains one ankyrin repeat domain. In this study, the crystal structure of hASB9-2 is shown at 2.2-Å resolution using molecular replacement. Overall, hASB9-2 forms a slightly curved arch with a characteristic L-shaped cross-section. Amino acid substitution analysis based on docking experiments revealed that His103 and Phe107 in hASB9-2 are essential for binding to CKB. Analysis of truncation mutants demonstrated that the first six ankyrin repeats along with the N-terminal region of hASB9-2 contribute to the interaction with CKB.
    The Protein Journal 03/2012; 31(4):275-84. · 1.04 Impact Factor
  • Article: A global genomic view on LNX siRNA-mediated cell cycle arrest.
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    ABSTRACT: LNX protein is the first described PDZ domain-containing member of the RING finger-type E3 ubiquitin ligase family. Studies have approved that LNX could participate in signal transduction, such as Notch pathway, and play an important role in tumorigenesis. In this study, we found that down-regulation of LNX resulted in G0/G1 cell cycle arrest in G0/G1 phase in HEK293 cells. To explore the molecular mechanism of this phenomenon, we employed expression microarray to comparatively analyze the genome-wide expression between the LNX-knockdown cells and the normal cells. We also used quantitative real-time PCR to further confirm the differential expression patterns of 25 transcripts involved in cell cycle. Combined with known information about genic functions, signal pathways and cell cycle machinery, we analyzed the role of endogenous LNX in cell cycle. The results suggest that down-regulation of LNX could result in cell cycle arrest in G0/G1 phase through inhibition of β-catenin, MAPK, NFκB, c-Myc-dependent pathway and activation of p53, TGF-β-dependent pathway. This study provides new perspectives on LNX's pleiotropic activities, especially its essential role in cell proliferation and cell cycle.
    Molecular Biology Reports 11/2010; 38(4):2771-83. · 2.93 Impact Factor
  • Article: Cellular and molecular mechanisms of photodynamic hypericin therapy for nasopharyngeal carcinoma cells.
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    ABSTRACT: Hypericin-mediated photodynamic therapy (HY-PDT) has become a potential treatment for tumors and nonmalignant disorders. Some studies reported that HY-PDT could lead to apoptosis in some carcinoma cells. However, the molecular mechanism of HY-PDT remains unknown. In this study, we evaluated the molecular mechanisms of hypericin associated with light-emitting diode irradiation on the poorly differentiated human nasopharyngeal carcinoma cell line CNE-2 in vitro. To comprehensively understand the effects of HY-PDT on CNE-2 cells, we detected cell viability, cell cycle, apoptosis, intracellular glutathione content, and intracellular caspase (caspase-9, caspase-3, and caspase-8) activity. Furthermore, we performed genome-wide expression analysis via microarrays at different time points in response to HY-PDT, and we found that differentially expressed genes were highly enriched in the pathways related to reactive oxygen species generation, mitochondrial activity, DNA replication and repair, cell cycle/proliferation, and apoptosis. These results were consistent with our cytology test results and demonstrated that caspase-dependent apoptosis occurred after HY-PDT. Taken together, both cellular and molecular data revealed that HY-PDT could inhibit the growth of CNE-2 cells and induce their apoptosis.
    Journal of Pharmacology and Experimental Therapeutics 09/2010; 334(3):847-53. · 3.83 Impact Factor
  • Article: Thiolated trimethyl chitosan nanocomplexes as gene carriers with high in vitro and in vivo transfection efficiency.
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    ABSTRACT: Trimethyl chitosan-cysteine conjugate (TMC-Cys) was evaluated as non-viral gene carriers to combine the advantages of TMC and thiolated chitosan. TMC-Cys with various molecular weights (30, 100, and 200 kDa) and quaternization degrees (15 and 30%) was allowed to form polyelectrolyte nanocomplexes with plasmid encoding enhanced green fluorescence protein (pEGFP), which demonstrated preferable diameters of below 200 nm and zeta potentials of +15 to +20 mV. Cell binding and uptake of TMC-Cys/pEGFP nanocomplexes (TMC-Cys NC) were enhanced 2.4-3.0 and 1.4-3.0 folds, respectively, compared to TMC/pEGFP nanocomplexes (TMC NC). pEGFP could be easily released from TMC-Cys NC at the intracellular glutathione concentration, which promoted its nuclear transport and accumulation. Consequently, TMC-Cys NC showed a 1.4 to 3.2-fold increase in the transfection efficiency in HEK293 cells as compared to TMC NC and the optimal TMC-Cys(100,30) NC showed a 1.5-fold enhancement than Lipofectamine2000. Such results were further confirmed by in vivo transfection with a 2.3-fold and 4.1-fold higher transfection efficiency of TMC-Cys(100,30) NC than TMC(100,30) NC and Lipofectamine2000, respectively. Therefore, TMC-Cys/DNA nanocomplexes could be a promising gene delivery system with in vitro and in vivo superiority to Lipofectamine2000.
    Journal of Controlled Release 05/2010; 144(1):46-54. · 5.73 Impact Factor
  • Article: System biology analysis of cell cycle pathway involved in hepatocellular carcinoma.
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    ABSTRACT: To investigate genetic mechanisms of hepatocarcinogenesis and identify potential anticancer targets in hepatocellular carcinoma (HCC), we analyzed microarray gene expression profiles between 33 HCCs and their corresponding noncancerous liver tissues. Functional analysis of differentially-expressed genes in HCC indicated that cell cycle dysregulation plays an important role in hepatocarcinogenesis. Based on 14 differentially-expressed genes involved in cell cycle in HCC, we applied Structural Equation Modeling (SEM) to establish a potential genetic network which could assist understanding of HCC molecular mechanisms. siRNA-mediated knock-down of two significantly up-regulated genes, minichromosome maintenance protein 2 (MCM2) and cyclin B1 (CCNB1), in HCC cells (SMMC-7721 and QGY-7703) induced G2/M-phase arrest, apoptosis and antiproliferation in HCC. Some up-regulated cell cycle-related genes in HCC were down-regulated following specific depletion of MCM2 or/and CCNB1 in HCC cells, which might well validate and complement the reconstructed cell cycle network. This study may contribute to further disclose hepatocarcinogenesis mechanism through systematically analyzed the HCC-related-cell-cycle pathway. This study also shows that MCM2 and CCNB1 could be promising prognostic and therapeutic targets for HCC.
    Frontiers in bioscience (Scholar edition) 01/2010; 2:1127-44.
  • Article: Expression profile reveals novel prognostic biomarkers in hepatocellular carcinoma.
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    ABSTRACT: The purpose of this study was to identify and validate novel prognostic biomarkers in human hepatocellular carcinoma (HCC). We analyzed gene expression profiles not only between 33 HCCs and their corresponding noncancerous liver tissues, but also between 25 HCCs and pooled normal liver tissues using cDNA microarrays containing 12800 genes. Functional analysis of differentially expressed genes involved in HCC carcinogenesis and tumor progression revealed that up-regulated and down-regulated genes are mainly associated with cell cycle and immune response, respectively. We detected two regions of cytogenetic changes only in poorly-differentiated HCCs using the expression data. We identified a 9-gene expression signature, which was able to predict differentiation degree and survival of HCC samples. Among the 9 most discriminatory genes, minichromosome maintenance protein 2 (MCM2), a significantly up-regulated gene involved in cell cycle pathway, was selected for further analysis. Overexpression of MCM2 protein related to poor-differentiation in HCC was validated using tissue microarray-based immunohistochemistry containing 96 HCCs. Our studies show that the 9-gene expression signature may serve as promising prognostic biomarkers involved in hepatocarcinogenesis and tumor progression.
    Frontiers in bioscience (Elite edition) 01/2010; 2:829-40.
  • Article: Methionine synthase A2756G polymorphism and cancer risk: a meta-analysis.
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    ABSTRACT: Polymorphisms in methionine synthase (MTR) gene may be involved in carcinogenesis by affecting DNA methylation. However, association studies on MTR A2756G polymorphism in cancers have reported conflicting results. Therefore we performed a meta-analysis to better assess the associations. A total of 24 896 cancer patients and 33 862 controls from 52 articles for MTR A2756G were investigated. Overall, individuals carrying MTR 2756GG genotype had a subtly reduced cancer risk under a recessive genetic model (odds ratio (OR), 0.92; P=0.053; 95% confidence interval (95% CI), 0.84-1.00; I(2)=0.0%; P(heterogeneity)=0.61). In the subgroup analyses by ethnicity, 2756GG was associated with a significantly reduced cancer risk in European populations (OR, 0.83; P=0.001; 95% CI, 0.74-0.93; I(2)=0.0%; P(heterogeneity)=0.99). However, in Asian populations, a significantly elevated association between 2756GG genotype and cancer risk was observed (OR, 1.33; P=0.012; 95% CI, 1.06-1.65; I(2)=0.0%; P(heterogeneity)=0.50). In studies stratified by tumor site, there was a significantly reduced risk of acute lymphoblastic leukemia (ALL) (OR, 0.54; P=0.049; 95% CI, 0.29-1.00; I(2)=10.7%; P(heterogeneity)=0.33) and colorectal cancer (OR, 0.63; P=0.004; 95% CI, 0.47-0.87; I(2)=0.0%; P(heterogeneity)=0.73) in European populations. Our study indicates that MTR A2756G polymorphism is a candidate gene polymorphism for cancer susceptibility regardless of environmental factors. Large-scale, well-designed, and population-based studies are required to further investigate gene-gene and gene-environment interactions on MTR A2756G polymorphism and tissue-specific cancer risk in an ethnicity-specific population.
    European journal of human genetics: EJHG 10/2009; 18(3):370-8. · 3.56 Impact Factor
  • Article: Androgen-responsive gene database: integrated knowledge on androgen-responsive genes.
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    ABSTRACT: Androgen signaling plays an important role in many biological processes. Androgen Responsive Gene Database (ARGDB) is devoted to providing integrated knowledge on androgen-controlled genes. Gene records were collected on the basis of PubMed literature collections. More than 6000 abstracts and 950 original publications were manually screened, leading to 1785 human genes, 993 mouse genes, and 583 rat genes finally included in the database. All the collected genes were experimentally proved to be regulated by androgen at the expression level or to contain androgen-responsive regions. For each gene important details of the androgen regulation experiments were collected from references, such as expression change, androgen-responsive sequence, response time, tissue/cell type, experimental method, ligand identity, and androgen amount, which will facilitate further evaluation by researchers. Furthermore, the database was integrated with multiple annotation resources, including National Center for Biotechnology Information, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway, to reveal the biological characteristics and significance of androgen-regulated genes. The ARGDB web site is mainly composed of the Browse, Search, Element Scan, and Submission modules. It is user friendly and freely accessible at http://argdb.fudan.edu.cn. Preliminary analysis of the collected data was performed. Many disease pathways, such as prostate carcinogenesis, were found to be enriched in androgen-regulated genes. The discovered androgen-response motifs were similar to those in previous reports. The analysis results are displayed in the web site. In conclusion, ARGDB provides a unified gateway to storage, retrieval, and update of information on androgen-regulated genes.
    Molecular Endocrinology 09/2009; 23(11):1927-33. · 4.54 Impact Factor
  • Article: LNX (Ligand of Numb-protein X) interacts with RhoC, both of which regulate AP-1-mediated transcriptional activation.
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    ABSTRACT: LNX (Ligand of Numb-protein X) was originally isolated as a binding partner to the cell-fate Determinant Numb during development, and then identified to act as a RING finger-type E3 ubiquitin ligase for the ubiquitylation and degradation of Numb. LNX contains 4 PDZ domains which are proved to play a central role in organizing diverse cell signaling assemblies. A yeast two-hybrid screening was used to identify LNX as a potential binding partner for RhoC. RhoC, a member of the Ras family of small GTPases, promotes reorganization of the actin cytoskeleton and regulation of cell shape, attachment, and motility. The interaction between LNX and RhoC in mammalian cells was identified by co-immunoprecipitation assays, and the efficient binding required the first PDZ domain of LNX. LNX and RhoC were further colocalized with each other in mammalian cells, in which RhoC changed its sublocalization from cytoplasm to nucleus when co-transferred with LNX. Furthermore, co-expression of RhoC reduced the transcriptional activity of AP-1, which was up-regulated by over-expression of LNX alone. These results suggest that LNX and RhoC might be part of a larger protein complex that would have important functions in signaling transduction about regulating the transcriptional activities of AP-1.
    Molecular Biology Reports 09/2009; 37(5):2431-7. · 2.93 Impact Factor
  • Article: Cloning and characterization of a novel splice variant of human U2AF1L3 gene†Full Length Research Paper
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    ABSTRACT: Pre-mRNA splicing allows individual genes to produce multiple protein isoforms with diverse functions. Recognition of functional splice sites in pre-mRNAs is very important in this splicing process and requires some protein auxiliary factors such as U2 small nuclear ribonucleoprotein auxiliary factor small subunit (U2AF35, encoded by U2AF1). By its RNA binding domains, U2AF35 interacts with U2AF65 to bind 3′ splice site of pre-mRNA and initiates splicing. Another protein, which is named as U2AF1-like3 (U2AF1L3), shows high similarity with U2AF35 and may have related function in pre-mRNA splicing. Here, we report a splice variant of U2AF1L3, which is 767 bp in length and has an open reading frame (ORF) coding a predicted 181 amino acids protein. Reverse transcription-PCR (RT-PCR) shows that this isoform has different expression pattern with U2AF1L3 and is highly expressed in heart, brain and lung.
    07/2009; 17(4):282-286.
  • Article: Sequence analysis of a human RhoGAP domain-containing gene and characterization of its expression in human multiple tissues†Full length research paper
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    ABSTRACT: Rho GTPase activating proteins (GAPs) stimulate the intrinsic GTP hydrolysis activity of Rho family proteins. Here we isolated a rhoGAP domain-containing protein gene with the same reading frame with ARHGAP19 gene, which has an ORF of 1485 bp encoding a putative protein of 494 amino acid residues with a predicted molecular mass of 55.806 kDa. Protein pattern analysis shows that it contains a bipartite nuclear localization signal (NLS) besides the rhoGAP domain, and it is consistent with the result of sub-cellular localization. ARHGAP19 is located in chromosome 10q24.1 and consists of 12 exons according to the Blastn result. Weak expression was detected in adult pancreas, spleen, thymus and ovary of the 16 adult tissues examined, while it had a more abundant expression pattern in eight important human fetal tissues. The expression pattern of ARHGAP19 shows it may have functions related to fetus development and gives us some clues on its probable functions in adult tissues.
    07/2009; 18(3):184-189.
  • Article: TP53 Arg72Pro polymorphism and lung cancer risk: a meta-analysis.
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    ABSTRACT: No clear consensus has been reached on the TP53 Arg72Pro polymorphism (G12139C) and lung cancer risk. Thus, a meta-analysis was conducted to summarize the possible association. There was no statistical association between 12139C (Pro allele) and lung cancer risk in Caucasians compared with 12139G allele. However, the association was observed in all subjects (9,387 patients and 9,922 controls, p=0.04, OR=1.08, 95% CI 1.00-1.17), as well as in Asians (p=0.0004, OR=1.14, 95% CI 1.06-1.22). The association was also found in Asians under recessive genetic model (p<0.00001, OR=1.37, 95% CI 1.20-1.57) and homozygote comparison (CC vs. GG) (p<0.0001, OR=1.34, 95% CI 1.16-1.56). 12139C allele might increase the lung adenocarcinoma risk compared with 12139G allele (p=0.01, OR=1.11, 95% CI 1.02-1.21), and the effect was also found under recessive genetic model (p=0.003, OR=1.28, 95% CI 1.09-1.50) and homozygote comparison (CC vs. GG) (p=0.007, OR=1.28, 95% CI 1.07-1.52). There was an elevated association between the 12139C and the stage I lung cancer under dominant genetic model (p=0.04, OR=1.48, 95% CI 1.02-2.16), but no association was observed in other stages. No association of smoking was found between 12139C allele and lung cancer under recessive genetic model. Our result indicated that 12139C might increase the risk of lung cancer under recessive genetic model in adenocarcinoma, in Asians, and in lung cancer stage I. More studies stratified for lung cancer stage-genotyping interaction should be performed to clarify the role of TP53 Arg72Pro polymorphism in the development of lung cancer.
    International Journal of Cancer 06/2009; 125(12):2903-11. · 5.44 Impact Factor
  • Article: Expression, purification and characterization of human ubiquitin-activating enzyme, UBE1.
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    ABSTRACT: UBE1 plays an important role in the first step of ubiquitin-proteasome pathway to activate ubiquitin. Both the structure and biochemical property research of human UBE1 protein, and the activity analysis of those enzymes which are related with ubiquitination pathway, are based on high purity of UBE1 protein. To obtain human UBE1 protein, the full length of human UBE1 was expressed in E. coli and purified by Ni-NTA superflow sepharose and strep-tactin sepharose which based on UB-UBE1 high-energy thioester bonded intermediate complex. It was demonstrated that purified UBE1 could activate and conjugate UB to ubiquitin-conjugating enzyme E2s. The purified large amount of UBE1 could be used for in vitro studies of ubiquitin pathway and structural studies.
    Molecular Biology Reports 05/2009; 37(3):1413-9. · 2.93 Impact Factor
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    Article: Global gene expression analysis reveals reduced abundance of putative microRNA targets in human prostate tumours.
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    ABSTRACT: Recently, microRNAs (miRNAs) have taken centre stage in the field of human molecular oncology. Several studies have shown that miRNA profiling analyses offer new possibilities in cancer classification, diagnosis and prognosis. However, the function of miRNAs that are dysregulated in tumours remains largely a mystery. Global analysis of miRNA-target gene expression has helped illuminate the role of miRNAs in developmental gene expression programs, but such an approach has not been reported in cancer transcriptomics. In this study, we globally analysed the expression patterns of miRNA target genes in prostate cancer by using several public microarray datasets. Intriguingly, we found that, in contrast to global mRNA transcript levels, putative miRNA targets showed a reduced abundance in prostate tumours relative to benign prostate tissue. Additionally, the down-regulation of these miRNA targets positively correlated with the number of types of miRNA target-sites in the 3' untranslated regions of these targets. Further investigation revealed that the globally low expression was mainly driven by the targets of 36 specific miRNAs that were reported to be up-regulated in prostate cancer by a miRNA expression profiling study. We also found that the transcript levels of miRNA targets were lower in androgen-independent prostate cancer than in androgen-dependent prostate cancer. Moreover, when the global analysis was extended to four other cancers, significant differences in transcript levels between miRNA targets and total mRNA backgrounds were found. Global gene expression analysis, along with further investigation, suggests that miRNA targets have a significantly reduced transcript abundance in prostate cancer, when compared with the combined pool of all mRNAs. The abnormal expression pattern of miRNA targets in human cancer could be a common feature of the human cancer transcriptome. Our study may help to shed new light on the functional roles of miRNAs in cancer transcriptomics.
    BMC Genomics 03/2009; 10:93. · 4.07 Impact Factor
  • Article: A strategy for meta-analysis of short time series microarray datasets.
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    ABSTRACT: Many time series microarray experiments have relatively short (less than ten) time points and lack in repeats, weakening the confidence of results. Combining the microarray data from different groups may improve the statistical power of detecting differentially expressed genes. However, few efforts have been taken to combine or compare the time-course array datasets generated by independent groups. Here we demonstrated a suitable strategy for meta-analysis of short time series microarray datasets and implemented this strategy on four published heat shock microarray datasets of Saccharomyces Cerevisiae. We first assessed the significance of each gene in each datasets based on area calculation and the null distribution of the areas. Then the similarity of significance values across datasets was assessed with meta-analysis methods, yielding a set of transient heat shock stress sensitive genes. Following correlation calculation helped us to combine the transformed data at the same time points of each gene. Further bioinformatic investigation showed the significance of our strategy, and also indicated some interesting features of regulatory systems in S. cerevisiae during transient heat stress.
    Frontiers in Bioscience 02/2009; 14:4058-70. · 3.52 Impact Factor
  • Article: Crystallization and preliminary X-ray analysis of the splice variant of human ankyrin repeat and suppressor of cytokine signaling box protein 9 (hASB9-2).
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    ABSTRACT: Human ankyrin repeat and suppressor of cytokine signaling box protein 9 (hASB9), a subunit of an Elongin C-cullin-SOCS box (ECS) E3 ubiquitin ligase complex, is believed to be involved in specific substrate-recognition for ubiquitination and degradation. In fact, this specific substrate-recognition is determined by the ankyrin repeats of hASB9 protein. Here, we have cloned and overexpressed the hASB9-2, the splice variant of hASB9 with only one ankyrin repeat domain, as a 6His-tagged recombinant protein in Escherichia coli. The purified hASB9-2 protein was crystallized by the hanging-drop vapor-diffusion technique and diffracted to 2.2A resolution. The data showed that the cubic hASB9-2 crystal belongs to space group P4(3)32 with unit-cell parameters (a=b=c=129.25A, alpha=beta=gamma=90 degrees). An asymmetric unit in the crystal was assumed to contain one protein molecule giving the Matthews Coefficient factor of 2.81 and the solvent content of 56.3%.
    Protein and Peptide Letters 02/2009; 16(3):333-5. · 1.94 Impact Factor
  • Article: Cloning, expression, and characterization of a thermostable PAP2L2, a new member of the type-2 phosphatidic acid phosphatase family from Geobacillus toebii T-85.
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    ABSTRACT: Most members of the type-2 phosphatidic acid phosphatase (PAP2) superfamily are integral membrane phophatases involved in lipid-related signal transduction and metabolism. Here we describe the cloning of a novel gene from Geobacillus toebii T-85, encoding a PAP2-like protein, Gtb PAP2L2, which contains 212 amino acids and shows a limited homology to other known PAP2s, especially at conserved phosphatase motifs, and a similar six-transmembrane topology structure. This enzyme was expressed, and purified in Escherichia coli. Recombinant Gtb PAP2L2s from the membrane fractions were solublized with 0.3% (v/v) Triton X-100 and purified by Ni(2+) affinity chromatography. The purified enzyme showed broad substrate specificity to phosphatidic acid, diacylglycerol pyrophosphate, and lysophosphatidic, but preferred phosphatidic acid and diacylglycerol pyrophosphate in vitro. Gtb PAP2L2 is a thermal stable enzyme with a half-life of 30 min at 60 degrees C. The enzyme was strongly inhibited by 1% SDS, 10 mM veranda, and Zn(2+), whereas it was independent of the Mg(2+) ion, and insensitive to N-ethylmaleimide. The purified recombinant Gtb PAP2L2 was catalytically active and highly stable, making it ideal as a candidate on which to base further PAP2 structure/function studies.
    Bioscience Biotechnology and Biochemistry 01/2009; 72(12):3134-41. · 1.28 Impact Factor
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    Article: Macrophage migration inhibitory factor (MIF) interacts with Bim and inhibits Bim-mediated apoptosis.
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    ABSTRACT: The pro-apoptotic Bcl-2 family member Bim acts as a sensor for apoptotic stimuli and initiates apoptosis through the mitochondrial pathway. To identify novel regulators of Bim, we employed the yeast two-hybrid system and isolated the human gene encoding macrophage migration inhibitory factor (MIF), a ubiquitously expressed proinflammatory mediator that has also been implicated in cell proliferation, the cell cycle and carcinogenesis. The interaction between MIF and Bim was confirmed by both in vitro and in vivo protein interaction assays. Intriguingly, protein complexes between MIF and the three major Bim isoforms (BimEL/BimL/BimS) could be detected in HEK293 and K562 cells, especially in cells undergoing apoptosis. Moreover, exogenous expression of MIF partially inhibited Bim-induced apoptosis in HEK293 cells. SiRNA-mediated knockdown of MIF increased apoptosis in K562 cells exposed to the chemical oxidant diamide. Endogenous MIF may regulate the pro-apoptotic activity of Bim and inhibit the release of cytochrome c from mitochondria.
    Molecules and Cells 09/2008; 26(2):193-9. · 2.18 Impact Factor

Institutions

  • 2001–2012
    • Fudan University
      • Institute of Genetics
      Shanghai, Shanghai Shi, China
  • 2005
    • Central South University
      • School of Resources Processing and Bioengineering
      Changsha, Hunan, China
  • 2004
    • Second Military Medical University, Shanghai
      Shanghai, Shanghai Shi, China
  • 2002–2004
    • Changhai Hospital, Shanghai
      Shanghai, Shanghai Shi, China
    • State Key Laboratory of Medical Genetics of China
      Changsha, Hunan, China
  • 2003
    • Huazhong University of Science and Technology
      Wuhan, Hubei, China
    • The Second Military Medical University
      Shanghai, Shanghai Shi, China