Project description:The red spider mite, Tetranychus evansi, is a oligophagous specialist mite pest of Solanaceae plants. Here, we described tomato transcriptional responses to T. evansi feeding and compared them to responses to tomato-adapted and -non-adapted strains of generalist herbivorous spider mite Tetranychus urticae. We used microarray to assess global gene expression in Solanum lycopersicum cv. Heinz 1706 upon T. evansi attack.
Project description:Proteins were extracted from tomato seedling (Heinz 1706) grown under 16-hour light/8-hour dark at 22 C for 4 days. Root consisted of ~3 cm from the tip and shoot consisted of cotyledons, meristems and ~1 cm hypocotyl. Proteins were then digested with either Trypsin/LysC or GluC, independently.
Project description:The environment has a profound influence on the tomato fruit organoleptic quality. The extent of which depends from a well-regulated and dynamic interplay among genes, metabolites and sensorial attributes. A systems biology approach, could be useful for elucidating complex interacting mechanisms regulating the plasticity of sensorial quality properties. In order to investigate the transcriptomic and metabolomic environmentally challenged remodeling and to evaluate organoleptic consequences of such variation, three tomato (Solanumlycopersisum) genotypes, Heinz 1706, San Marzano and Vesuviano were grown in two different localities. The metabolome and transcriptome analysis revealed common as well as genotype specific challenged pathways, the dynamic of which are in turn regulated by genome organization and gene diversity. When combined with sensorial data, through a network analysis, interesting aspects of fruit quality fine regulation were revealed: first, duplicated genes and different genes/isoforms and transcription factors have a dominant role in shaping environment response; second the lost or gained interactions and/or the changing position of a node is crucial for phenotypic expression of a given trait; third, sensorial traits as sweetness, turgidity and are much responsive to environment. The fundamental role of cell wall metabolism in tuning all the quality attributes was also highlighted. Tomato genotypes, although activate the same fruit related quality processes, follow different transcriptomic, metabolomic and sensorial trajectories depending of their own genetic makeup.
Project description:Tomato fruit ripening is associated with a dramatic increase in susceptibility to the fungal pathogen Botrytis cinerea, the causal agent of gray mold. Mature green fruit, prior to ripening, are largely resistant to B. cinerea, whereas red fruit, at the end of ripening, are susceptible to B. cinerea infection. We used microarrays to detail the gene expression changes that are induced by B. cinerea when tomato fruit at unripe and ripe stages are infected. Experiment Overall Design: Tomato fruit at mature green and red ripe stages were wound inoculated with a water suspension of B. cinerea conidia. Twenty four hours post inoculation fruit pericarp and epicarp tissue around and including the inoculation sites was collected and the total RNA extracted. Total RNA was also collected from healthy and mock inoculated fruit.
Project description:Gene expression in three stages of ripening tomato fruit (variety Ailsa Craig) was determined with the EUTOM3 Affymetrix array in order to compare with degradrome sequencing data from study GSE42661, treated as RNAseq. three replicates of each stage (MG, mature green; T, turning/breaker; RR, red ripe) were hybridized; Expression values were normalized for each sample and reported by iTAG2.3 cDNA identifier in the accompanying matrix table.
Project description:Tomato fruit ripening is associated with a dramatic increase in susceptibility to the fungal pathogen Botrytis cinerea, the causal agent of gray mold. Mature green fruit, prior to ripening, are largely resistant to B. cinerea, whereas red fruit, at the end of ripening, are susceptible to B. cinerea infection. We used microarrays to detail the gene expression changes that are induced by B. cinerea when tomato fruit at unripe and ripe stages are infected. Keywords: plant responses to pathogens
Project description:The increased susceptibility of ripe fruit to fungal pathogens poses a substantial threat to crop production and marketability. Here, we coupled transcriptomic analyses with mutant studies to uncover critical genes and processes governing ripening-associated susceptibility in tomato (Solanum lycopersicum) fruit. Using wild-type unripe and ripe fruit inoculated with three fungal pathogens—Botrytis cinerea, Fusarium acuminatum, and Rhizopus stolonifer—we identified common pathogen response genes reliant on chitinases, WRKY transcription factors, and reactive oxygen species detoxification. Interestingly, susceptible ripe fruit demonstrated a more extensive defense response than resistant unripe fruit, indicating that the magnitude and diversity of defense response does not significantly impact the interaction. To tease apart individual features of ripening that may be responsible for susceptibility, we utilized three tomato non-ripening mutants: Cnr, rin and nor. Fruit from these mutants displayed different patterns of susceptibility to fungal infection. Functional analysis of the genes altered during ripening in the susceptible genotypes revealed losses in the maintenance of cellular redox homeostasis. Moreover, jasmonic acid accumulation and signaling coincided with the activation of defenses in resistant fruit. Lastly, based on high gene expression in susceptible fruit, we identified and tested two candidate susceptibility factors, pectate lyase (PL) and polygalacturonase (PG2a). CRISPR-based knockouts of PL, but not PG2a, resulted in more than 50% decrease in the susceptibility of ripe fruit, demonstrating that PL is a major susceptibility factor. Ultimately, this study demonstrates that targeting specific genes that drive susceptibility is a viable strategy to improve resistance of tomato fruit against fungal pathogens.
Project description:Worldwide, 20-25% of all harvested fruit and vegetables are lost annually in the field and throughout the postharvest supply handling chain due to spoilage by fungal pathogens. Most impactful postharvest pathogens exhibit necrotrophic lifestyles, resulting in rotting of the host tissues and complete loss of marketable commodities. Necrotrophic fungi can readily infect ripe fruit leading to the rapid establishment of disease symptoms. However, these pathogens generally fail to infect unripe fruit, or remain quiescent until host and environmental conditions stimulate a successful infection. Current research on necrotrophic infections of fruit was mainly focused on the host by characterizing genetic and physicochemical factors that inhibit or promote the disease. However, the pathogenicity and virulence strategies employed by necrotrophic pathogens in ripe and unripe fruit are mostly understudied. Here, we provide a first comparative transcriptomics study of fungal postharvest pathogens: Botrytis cinerea, Rhizopus stolonifer and Fusarium acuminatum, all of which display necrotrophic behavior when infecting fruit. We de novo assembled and annotated the transcriptomes of R. stolonifer, and F. acuminatum and performed a differential gene expression analysis comparing the three fungal transcriptomes during fruit infection with that of fungal in-vitro growth. Analysis of the differentially expressed genes for enrichment of functional annotations revealed shared strategies of the three fungi during infection of compatible (ripe fruit) and incompatible (unripe fruit) hosts. We furthermore selected candidate genes that are involved in these strategies to characterize their expression during infection of unripe and ripe-like fruit of the non-ripening (nor) tomato mutant, both of which are physiologically and biochemically similar to unripe wildtype fruit. By enabling a better understanding of fungal necrotrophic infection strategies, we move closer to generating accurate models of fruit diseases and development of early detection tools and effective management strategies.
Project description:In this study, we explored the metabolome and transcriptome of the ripe fruit in nine landrace accessions representing the seven genetic groups and compared them to the mature fruit of the wild progenitor S. pimpinellifolium. The goal is to shed light in understanding the factors responsible for acquiring tomato fruit quality (taste and flavour) at molecular level during the domestication process.