Gustavo Gomez

Gustavo Gomez
Institute for Integrative Systems Biology (I2SysBio - CSIC-UV) · Molecular Interaction and Regulation

PhD

About

80
Publications
8,069
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,599
Citations
Additional affiliations
July 1999 - October 2016
Institute for Integrative Systems Biology (I2SysBio - CSIC-UV)
Position
  • Principal Investigator

Publications

Publications (80)
Article
It is well known that viroids promote significant alterations at diverse host regulatory levels. However the mechanisms by which these tiny RNAs subvert endogenous regulatory networks remain a to a large extent unsolved question. In the last years diverse studies have revealed the existence of a close interplay between viroid infection and host DNA...
Preprint
Gene silencing for functional studies in plants has been largely facilitated by manipulating viral genomes with inserts from host genes to trigger virus induced gene silencing (VIGS) against the corresponding mRNAs. However, viral genomes encode multiple proteins and disrupt plant homeostasis by interfering with endogenous cell mechanisms. To circu...
Preprint
Full-text available
Constricted by an extreme biological simplicity, viroids are compelled to subvert host regulatory networks in order to accomplish their infectious process. Most of the studies focused on the response to viroid infection have only addressed a specific host regulatory level and considered a unique infection time. Thus, much remains to be done if we w...
Article
Full-text available
Climate change has been associated with a higher incidence of combined adverse environmental conditions that can promote a significant decrease in crop productivity. However, knowledge on how a combination of stresses might affect plant development is still scarce. MicroRNAs (miRNAs) have been proposed as potential targets for improving crop produc...
Article
Full-text available
Circular RNAs (circRNAs) are regulatory molecules involved in the modulation of gene expression. Although originally assumed as non-coding RNAs, recent studies have evidenced that animal circRNAs can act as translatable transcripts. The study of plant-circRNAs is incipient, and no autonomous coding plant-circRNA has been described yet. Viroids are...
Preprint
Full-text available
Climate change has been associated with a higher incidence of combined adverse environmental conditions that can promote a significant decrease in crop productivity. However, knowledge on how a combination of stresses might affect plant development is still scarce. MicroRNAs (miRNAs) have been proposed as potential targets for improving crop-produc...
Article
Full-text available
Infectious viroid clones consist of dimeric cDNAs used to generate transcripts which mimic the longer-than-unit replication intermediates. These transcripts can be either generated in vitro or produced in vivo by agro-inoculation. We have designed a new plasmid, which allows both inoculation methods, and we have compared them by infecting Solanum l...
Article
Full-text available
Taxonomy: Hop stunt viroid (HSVd) is the type species of the genus Hostuviroid (family Pospiviroidae). The other species of this genus is Dahlia latent viroid, which presents an identical central conserved region (CCR) but lacks other structural hallmarks present in Hop stunt viroid. HSVd replication occurs in the nucleus through an asymmetric rol...
Poster
Full-text available
Efficient inoculation methods are the basis of studies on viroid-host interactions. Traditional inoculation methods based on the use of sap extracts or grafting procedures are often inefficient and non-reproducible. We have recently developed a method that allows the efficient cDNA dimer production into a binary vector ready for agro-inoculation. H...
Article
Although epigenetic factors may influence the expression of defense genes in plants, their role in antiviral responses and the impact of viral adaptation and evolution in shaping these interactions are still poorly explored. We used two isolates of turnip mosaic potyvirus (TuMV) with varying degrees of adaptation to Arabidopsis thaliana to address...
Preprint
Full-text available
Although epigenetic factors may influence the expression of defense genes in plants, their role in antiviral responses and the impact of viral adaptation and evolution in shaping these interactions are still poorly explored. We used two isolates of turnip mosaic potyvirus (TuMV) with varying degrees of adaptation to Arabidopsis thaliana to address...
Poster
Full-text available
Any external factor that imposes a negative impact on plant growth and development is recognized as a stress inducer. Because of their sessile nature, plants have evolved sophisticated and robust mechanisms to favor a certain degree of transcriptional plasticity to cope with stress. Epigenetic regulation of the genome is a key regulatory mechanism...
Article
miRNAs are small RNAs that regulate mRNAs at both transcriptional and posttranscriptional level. In plants, miRNAs are involved in the regulation of different processes including development and stress-response. Elucidating how stress-responsive miRNAs are regulated is key to understand the global response to stress but also to develop efficient bi...
Preprint
Full-text available
miRNAs are small RNAs that regulate mRNAs at both transcriptional and posttranscriptional level. In plants, miRNAs are involved in the regulation of different processes including development and stress-response. Elucidating how stress-responsive miRNAs are regulated is key to understand the global response to stress but also to develop efficient bi...
Article
Full-text available
Background: Viroid research generally relies on infectious cDNA clones that consist of dimers of the entire viroid sequence. At present, those dimers are generated by self-ligation of monomeric cDNA, a strategy that presents several disadvantages: (i) low efficiency, (ii) it is a non-oriented reaction requiring tedious screenings and (iii) additio...
Article
Small interfering RNAs (siRNA) are key regulators of gene expression that play essential roles in diverse biological processes. Trans-acting siRNAs (tasiRNAs) are a class of plant-endogenous siRNAs that lead the cleavage of non-identical transcripts. TasiRNAs are usually involved in fine-tuning development. However, increasing evidence supports tha...
Article
Full-text available
Background MiRNAs have emerged as key regulators of stress response in plants, suggesting their potential as candidates for knock-in/out to improve stress tolerance in agricultural crops. Although diverse assays have been performed, systematic and detailed studies of miRNA expression and function during exposure to multiple environments in crops ar...
Article
Full-text available
Abstract miRNAs are fundamental endogenous regulators of gene expression in higher organisms. miRNAs modulate multiple biological processes in plants. Consequently, miRNA accumulation is strictly controlled through miRNA precursor accumulation and processing. Members of the miRNA319 family are ancient ribo-regulators that are essential for plant de...
Poster
MiRNAs are a class of small (20-24 nts in length) non-coding RNAs widely distributed in Eukariota. Functionally, miRNAs regulate gene expression at the post-transcriptional level mediating cleavage or translational repression of their mRNA target. In plants, only a few annotated MIRNA gene families are highly conserved from mosses to higher floweri...
Chapter
Studies on viroid-host interactions have become essential to understand different aspects of the structure-function relationships in the RNA world. Work on viroid RNA has led to seminal discoveries in RNA biology. Over the last two decades, significant progress has been made as to how viroid RNA traffics within and among cells, and how these noncod...
Chapter
Many hypotheses have been advanced to explain how viroid infection might alter host gene expression to produce the symptoms seen on diseased plants. Only recently, however, has a series of technological advances allowed these hypotheses to be tested experimentally. The first section of this chapter describes changes in the host proteome following v...
Article
Eukaryotic organisms exposed to adverse conditions are required to show a certain degree of transcriptional plasticity in order to cope successfully with stress. Epigenetic regulation of the genome is a key regulatory mechanism allowing dynamic changes of the transcriptional status of the plant in response to stress. The Hop stunt viroid (HSVd) ind...
Article
Viroids - ancient plant-pathogenic long noncoding RNAs - have developed a singular evolutionary strategy based on reprogramming specific phases of host-metabolism to ensure that their infection cycle can be completed in infected cells. However, the molecular aspects governing this transregulatory phenomenon remain elusive. Here, we use immunoprecip...
Article
Full-text available
In a survey of viral diseases conducted in November 2014 in Imbabura Province, Ecuador, we observed severe yellow mosaic, chlorosis, and leaf deformation symptoms in approximately 70% of the red pepper (Capsicum annuum) plants. In Ecuador, pepper production in 2012 was estimated at 5,500 tons cultivated on 1,700 ha (FAOSTAT). Although nearly 90% of...
Article
ncreasing evidence points to the epigenetic regulation of the transcriptional activity as a general mechanism controlling host-response to pathogen-infection. Recent results revealed that cucumber plants infected with Hop stunt viroid (HSVd) showed alterations in the DNA methylation-pattern of usually silenced rRNA-genes that are consequently trans...
Article
Full-text available
Viroids are plant-pathogenic non-coding RNAs able to interfere with as yet poorly known host-regulatory pathways and to cause alterations recognized as diseases. The way in which these RNAs coerce the host to express symptoms remains to be totally deciphered. In recent years, diverse studies have proposed a close interplay between viroid-induced pa...
Article
Full-text available
RNA-binding proteins (RBPs) govern a myriad of different essential processes in eukaryotic cells. Recent evidence reveals that apart from playing critical roles in RNA metabolism and RNA transport, RBPs perform a key function in plant adaptation to various environmental conditions. Long-distance RNA transport occurs in land plants through the phloe...
Article
Plant material free of pests and diseas es is an essential requirement for obtaining high fruit quality in productive orchards. Unfortunately, the increase of genetic diversity has prevailed until now in most germplasm collections over the health status of the accessions. As a cons equence, most fruit tree germplasm collec- tions are infected with...
Article
Full-text available
Viroids belonging to the family Avsunviroidae are the only functional RNAs known to traffic selectively into chloroplasts. Subcellular targeting is a critical step in guaranteeing their access to the machineries involved in their replication. However, the host mechanisms exploited by these non coding pathogenic RNAs to be selectively imported into...
Article
A large body of evidence has lead to the suggestive proposal of a potential interplay between viroid-induced pathogenesis and RNA silencing regulatory mechanisms. A variety of techniques have been used to examine this interaction. This chapter outlines the use of a green fluorescent protein (GFP) sensor, containing viroid-specific sequence targets...
Article
Full-text available
Intracellular RNA-trafficking and specific subcellular compartmentalization are key regulatory processes controlling gene expression. Viroids are plant-pathogenic non-coding RNAs that specifically replicate in the nucleus (family Pospiviroidae) or chloroplasts (Avsunviroidae) of infected cells. Subcellular compartmentalization is a critical step in...
Data
Northern blot detection of miR159, miR167 and miR168 in cucumber plants. The leaves were collected weekly from 4 (one group for week) independent groups of 3 different plants and pooled, before the RNA extraction. The samples were recovered at 5, 6, 7 and 8 weeks after germination (lanes 1 to 4, respectively). The 3 different plant sectors analyzed...
Data
Conserved and known but non-conserved miRNA families predicted by miRCat in cucumber transcriptome. (DOC)
Article
Full-text available
Micro RNAS (miRNAs) are a class of endogenous small non coding RNAs involved in the post-transcriptional regulation of gene expression. In plants, a great number of conserved and specific miRNAs, mainly arising from model species, have been identified to date. However less is known about the diversity of these regulatory RNAs in vegetal species wit...
Article
The import of diverse nucleus-encoded proteins into chloroplasts is crucial for plant life. Although this crosstalk is mainly dependent on specific transit peptides, it has been recently reported that a non protein-coding RNA (ncRNA) based on a viroid-derived sequence (vdRNA) and acting as a 5´UTR-end mediates the functional import of GFP-mRNA into...
Article
Full-text available
Communication between chloroplasts and the nucleus is one of the milestones of the evolution of plants on earth. Proteins encoded by ancestral chloroplast-endogenous genes were transferred to the nucleus during the endosymbiotic evolution and originated this communication, which is mainly dependent on specific transit-peptides. However, the identif...
Article
Small RNA (sRNA)-guided processes, referred to as RNA silencing, regulate endogenous and exogenous gene expression. In plants and some animals, these processes are noncell autonomous and can operate beyond the site of initiation. Viroids, the smallest self-replicating plant pathogens known, are inducers, targets and evaders of this regulatory mecha...
Article
Full-text available
We suggest that viroids are trapped into adaptive peaks as the result of adaptive constraints. The first one is imposed by the necessity to fold into packed structures to escape from RNA silencing. This creates antagonistic epistases, which make future adaptive trajectories contingent upon the first mutation and slow down the rate of adaptation. Th...
Article
Full-text available
In this paper, we report a large-scale survey for the incidence of Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd) in stone fruit collections and commercial orchards in the Czech Republic. From the 645 samples analysed, PLMVd was detected in 80 (26.6%) of peaches and the HSVd in 3 (1.3%) of apricot and 1 (0.33%) of peach trees. Sixty...
Article
Of all known plant pathogens, viroids have the lowest biological complexity. Their genome consists of a naked RNA without protein-encoding capacity. However, viroids contain sufficient genetic information to establish infection in susceptible hosts. The process by which this tiny RNA subverts the plant cell machinery by coercing the host to express...
Article
Full-text available
Viroids are small self-replicating RNAs that infect plants. How these noncoding pathogenic RNAs interact with hosts to induce disease symptoms is a long-standing unanswered question. Recent experimental data have led to the suggestive proposal of a pathogenic model based on the RNA silencing mechanism. However, evidence of a direct relation between...
Article
China-tree or paraiso (Melia azedarach) decline, caused by a phytoplasma, is a disease in Argentina for which hitherto no diagnostic reagents were available. The production of a polyclonal antiserum using a purification protocol involving a double Percoll gradient is reported. The antiserum was used successfully in immuno-dot blot assay to discrimi...
Article
Full-text available
Viroids are sub-viral plant pathogens consisting of covalently closed circular RNAs that infect herbaceous and woody hosts. They do not code for any peptide or protein and therefore are fully dependent on the host machinery for most biological processes, including pathogenesis. Certain viroid-host combinations show severe symptoms but the biochemic...
Article
Full-text available
Tissue-imprint hybridization (TIH) assay was validated for large-scale detection of Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd). All 72 collected leaves (100%) from 2 PLMVd- and 2 HSVd-infected trees were positive in TIH, regardless of the geographic orientation of the scaffold, level of the canopy and position of the leaf in the...
Article
Viroids, small non-coding pathogenic RNAs, are able to induce RNA silencing, a phenomenon that has been associated with the pathogenesis and evolution of these small RNAs. It has been recently suggested that viroids may resist this plant defense mechanism. However, the simultaneous degradation of non-replicating full-length viroid RNA, and the resi...
Article
Viroids are small, single-stranded, circular, non-coding pathogenic RNAs. Hop stunt viroid (HSVd) is characterized by possesses rod-like structure and replicate in the host nuclei. Green fluorescent protein (GFP) fusions with transit sequences or entire proteins can be used for deliberate labelling of particular cell compartments. Different GFP-fus...
Article
Full-text available
The province of Murcia (Murcia Region) is the one of the most important apricot growing regions in Europe. In recent years a fruit disorder named by growers as “degeneración” has been detected in apricot commercial orchards of this region, mainly in the variety Velázquez Fino. Affected fruits are characterized by changes in their external appearanc...
Article
SUMMARY Viroids are small, single-stranded, circular, pathogenic RNAs that do not code for proteins and thus depend on host factors for their replication and movement. They induce diseases in plants by direct interaction with host factors through a mechanism as yet unidentified. Hop stunt viroid (HSVd) has been found in a wide range of herbaceous a...
Article
Full-text available
A functional genomics project has been initiated to approach the molecular characterization of the main biological and agronomical traits of citrus. As a key part of this project, a citrus EST collection has been generated from 25 cDNA libraries covering different tissues, developmental stages and stress conditions. The collection includes a total...
Article
Phloem proteins (P-proteins) are an enigmatic group of proteins present in most angiosperm species. The best characterized P-proteins (PP1 and PP2) are synthesized in companion cells, transported into sieve elements via pore plasmodesmata and translocated through the plant. Characteristics such as long-distance translocation, RNA-binding activity a...
Article
Full-text available
"Tissue-printing" hybridization (3) for Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd) was used to assess the sanitary status of stone fruit accessions in the Canadian Clonal Genebank (CCG) located in Harrow (Ontario). The Prunus spp. accessions in the CCG are primarily of Canadian origin; other countries of origin include the Unite...
Article
Full-text available
Viroids are highly structured plant pathogenic RNAs that do not code for any protein, and thus, their long-distance movement within the plant must be mediated by direct interaction with cellular factors, the nature of which is presently unknown. In addition to this type of RNAs, recent evidence indicates that endogenous RNAs move through the phloem...
Article
The two viroids known to affect stone fruit trees are Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd). Viroids can be detected by biological, biochemical or molecular methods. The two first approaches are time consuming and expensive, with the limiting step for molecular techniques being the sample preparation process. In the present...
Article
Two phytoplasmas closely related to the X-disease group were associated with China-tree (Melia azedarach L.) and garlic (Allium sativum L.) decline diseases in Argentina. The present work was aimed at studying their phylogenetic relationship based on molecular characterization of the 16S ribosomal DNA sequences. Phytoplasma DNAs were obtained from...