Project description:Here, we found that the tomato jmjC domain-containing gene SlJMJ6 encodes a histone lysine demethylase that specifically demethylates H3K27 methylation. Overexpression of SlJMJ6 accelerated fruit ripening in tomato, which is associated with the up-regulated expression of a large number of ripening-related genes. Integrated analysis of RNA-seq and ChIP-seq data identified 55 genes that are targeted directly by SlJMJ6 and transcriptionally up-regulated with decreased H3K27m3 in SlJMJ6 overexpressing (SlJMJ6-OE) fruits. A large number of the SlJMJ6-regulated genes are involved in transcription regulation, ethylene biosynthesis, cell wall degradation, pigment biosynthesis, and hormone signaling. Fourteen ripening-related genes including RIN, ACS4, ACO1, PL, TBG4 were confirmed to be directly regulated by SlJMJ6 through removing H3K27me3. Taken together, these results indicated that SlJMJ6 is a ripening prompting H3K27me3 demethylase that activates the expression of the ripening-related genes by modulating H3K27me3, thereby facilitating fruit ripening in tomato. To our knowledge, this is the first report of the involvement of a histone lysine demethylase in the regulation of fruit ripening.
Project description:For exploring whether mRNA m6A modification participates in the regulation of tomato fruit ripening, we performed m6A-seq in three tomato fruit samples, including wild-type (WT) at 39 days post-anthesis (DPA) and 42 DPA, and Cnr mutant at 42 DPA, with three biological replicates. mRNA methylome analysis reveals that m6A methylation is a prevalent modification in mRNA of tomato fruit and the m6A sites are predominantly enriched in the stop codon and 3’ untranslated region, where m6A deposition has been proved to negatively correlate with gene expression. Hundreds of ripening-induced and ripening-repressed genes, including the SlDML2, were found to harbour changed m6A levels during fruit ripening or in the Cnr mutant, implicating the involvement of m6A modification in the regulation of fruit ripening.
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:Fruit set is triggered after ovule fertilization, as a consequence of the downregulation of ovary growth repressors, such as the tomato transcription factors Auxin/indole-3-acetic acid 9 (IAA9) and Agamous-like 6 (AGL6). We produced small RNA libraries from IAA9- and AGL6-silenced ovaries to identify miRNAs differentially expressed in IAA9- and AGL6-silenced ovaries as compared with unpollinated control ovaries. The identified miRNAs represent a pool of regulatory sRNAs potentially involved in tomato fruit initiation.
Project description:To further clarify the differences in the potential regulatory mechanisms of cold tolerance between wild and cultivated tomatoes, we subjected cold-sensitive cultivated tomato (Solanum lycopersicum) Ailsa Craig (AC) and cold-tolerant wild tomato (S. habrochaites) LA1777 to cold stress for 6 h, and performed ATAC-Seq and RNA-Seq, respectively.
Project description:By using parallel analysis of RNA ends (PARE) for global identification of miRNA targets and comparing four different stages of tomato fruit development we identified a large number of target genes of miRNAs. PARE libraries were produced, one each, for tomato fruits at 5 days after pollination, mature green fruit, Breaker fruit, and 7 days after Breaker stge fruits
