Project description:The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers) is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. Transcriptomic profiles of the 7B-1 male-sterile and wild type (WT) anthers were studied using mRNA sequencing (RNA-Seq). In total, 768 differentially expressed genes (DEGs) were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO) enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturation, dysfunctional meiosis, arrested microspores, defect in callose degradation and abnormal tapetum development. TUNEL assay showed a defect in programmed cell death (PCD) of tapetal cells in 7B-1 anthers. The present study provides insights into the transcriptome of the 7B-1 mutant. We identified several genes with altered expression level in 7B-1 (including beta-1,3 glucanase, GA2oxs, cystatin, cysteine protease, pectinesterase, TA29, and actin) that could potentially regulate anther developmental processes, such as meiosis, tapetum development, and cell-wall formation/degradation.
Project description:The function of the plant hormone jasmonic acid (JA) in development of tomato flowers was analyzed with a mutant defective in JA perception (jasmonate-insensitive1-1, jai1-1). In contrast to Arabidopsis JA-insensitive plants that are male sterile, the tomato mutant jai1-1 exhibits major defects in female development resulting in female sterility. To identify putative JA-dependent regulatory components, transcriptomics was performed using isolated ovules of three different stages of flower development, from both wild type and jai1-1. Among the strongly down-regulated genes in jai1-1, one encoding a MYB transcription factor (SlMYB21) was found. Its orthologue in Arabidopsis has a crucial role in JA-regulated stamen development. SlMYB21 showed transcription factor activity in yeast, interaction with SlJAZ9 in yeast and in planta, and complemented the Arabidopsis mutant myb21-5. To analyze SlMYB21 function in tomato ovule development, CRISPR/Cas9 mutants were created and a TILLING mutant was identified, all showing female sterility and therefore corroborating a function of MYB21 in tomato ovule development. Transcriptomics from wild type, jai1-1 and myb21-2 carpels revealed processes that might be controlled by SlMYB21. The data suggest a positive regulation of JA biosynthesis by SlMYB21, but a negative regulation of the action of auxin and GA. The results demonstrate that SlMYB21 mediates at least partially the action of JA and might control the flower to fruit transition.
Project description:The function of the plant hormone jasmonic acid (JA) in development of tomato flowers was analyzed with a mutant defective in JA perception (jasmonate-insensitive1-1, jai1-1). In contrast to Arabidopsis JA-insensitive plants that are male sterile, the tomato mutant jai1-1 exhibits major defects in female development resulting in female sterility. To identify putative JA-dependent regulatory components, transcriptomics was performed using isolated ovules of three different stages of flower development, from both wild type and jai1-1. Among the strongly down-regulated genes in jai1-1, one encoding a MYB transcription factor (SlMYB21) was found. Its orthologue in Arabidopsis has a crucial role in JA-regulated stamen development. SlMYB21 showed transcription factor activity in yeast, interaction with SlJAZ9 in yeast and in planta, and complemented the Arabidopsis mutant myb21-5. To analyze SlMYB21 function in tomato ovule development, CRISPR/Cas9 mutants were created and a TILLING mutant was identified, all showing female sterility and therefore corroborating a function of MYB21 in tomato ovule development. Transcriptomics from wild type, jai1-1 and myb21-2 carpels revealed processes that might be controlled by SlMYB21. The data suggest a positive regulation of JA biosynthesis by SlMYB21, but a negative regulation of the action of auxin and GA. The results demonstrate that SlMYB21 mediates at least partially the action of JA and might control the flower to fruit transition.
Project description:We report a mutant that has defective pollens and abnormal anthers from its semi-sterile mutant (sstl) progeny segregates. Comparative transcriptomics analysis illustrates the mechanism of male sterility.
Project description:To characterize the PTI response of tomato and the effect of the delivery of a subset of effectors, we performed an RNA-seq analysis of tomato Rio Grande prf3 leaves challenged with either the flgII-28 peptide or the following bacterial strains: Agrobacterium tumefaciens GV2260, Pseudomonas fluorescens 55, Pseudomonas putida KT2440, Pseudomonas syringae pv. tomato (Pst) DC3000, Pst DC3000 deltahrcQ-U deltafliC and Pst DC3000 deltaavrPto deltaavrPtoB. NOTE: Samples in SRA were assigned the same sample accession. This is incorrect as there are different samples, hence âSource Nameâ was replaced with new values. Comment[ENA_SAMPLE] contains the original SRA sample accessions.