Project description:Petunia floral scent production and emission is highly regulated, with a major role for the transcription factor ODORANT1 (ODO1) in directing activation of volatile biosynthesis. Using ChIP-seq of tagged ODO1 protein from petunia flowers, and RNA-seq of wild-type and odo1i RNAi flowers, the ODORANT1-regulated gene network of petunia is described, which extends to branches involved in phenylpropanoid intermediate production and S-adenosyl-methionine biosynthesis to potentiate production and emission of volatiles. Analysis of direct targets of regulation has also enabled the identification of an ODO1 binding motif.
Project description:Petunia is an excellent model system, especially for genetic, physiological and molecular studies. Thus far, however, genome-wide expression analysis has been rarely applied because of the lack of sequence information. We applied next-generation sequencing to generate, through de novo read assembly, a large catalogue of transcripts for Petunia axillaris and Petunia inflata. On the basis of the transcriptome of each species, comprehensive microarray chips for gene expression analysis were established and used for the analysis of global- and organ-specific gene expression in both species. In addition, microarray analysis was applied to explore the molecular basis of the seed coat defects in Petunia hybrida mutants, homozygous for a null allele of the AN11 gene, encoding a WDR transcription regulator. Among the transcripts differentially expressed in an11 seeds compared to wild type, many expected targets of AN11 were found but also several interesting new candidates that might play a role in morphogenesis of the seed coat. Our results validate the combination of next-generation sequencing with microarray analyses strategies to identify the transcriptome of two petunia species without previous knowledge of their genome, and to develop comprehensive chips as useful tools for the analysis of gene expression in P. axillaris, P. inflata and P. hybrida.
Project description:Petunia is an excellent model system, especially for genetic, physiological and molecular studies. Thus far, however, genome-wide expression analysis has been rarely applied because of the lack of sequence information. We applied next-generation sequencing to generate, through de novo read assembly, a large catalogue of transcripts for Petunia axillaris and Petunia inflata. On the basis of the transcriptome of each species, comprehensive microarray chips for gene expression analysis were established and used for the analysis of global- and organ-specific gene expression in both species. In addition, microarray analysis was applied to explore the molecular basis of the seed coat defects in Petunia hybrida mutants, homozygous for a null allele of the AN11 gene, encoding a WDR transcription regulator. Among the transcripts differentially expressed in an11 seeds compared to wild type, many expected targets of AN11 were found but also several interesting new candidates that might play a role in morphogenesis of the seed coat. Our results validate the combination of next-generation sequencing with microarray analyses strategies to identify the transcriptome of two petunia species without previous knowledge of their genome, and to develop comprehensive chips as useful tools for the analysis of gene expression in P. axillaris, P. inflata and P. hybrida. The manuscript describes the creation by next generation sequencing of a large catalogue of the transcriptome of the two Petunia species, that are considered to represent the natural material from which the breeders selected their varieties. This submission represents the transcriptome component of study. The high throughput sequencing data were submitted to SRA (accession numbers: SRA027293, SRP004866.1, SRX036999.2, SRX036998.2).