ODO1 regulates the timing of internal volatile production in Petunia hybrida, and possibly influences the volatile composition.

Data Repository Bachelor Thesis Nina Borsboom.

To attract the right pollinators, Petunia hybrida emits its floral fragrance at night. The temporal emission of fragrance is regulated by transcription factors such as EMISSION OF BENZENOIDS I & II (EOBI & EOBII) and ODORANT1 (ODO1). The timed expression of ODO1, determines the timing of volatile emission. The expression of ODO1 is negatively regulated by LATE ELONGATED HYPOCOTYL (LHY). LHY represses ODO1 transcription by binding to ‘evening elements’ (EEs) in the promoter region of ODO1. In this study the effect of ODO1 on the production of internal volatiles and the volatile composition is researched by determining the gene expression levels of ODO1, EPSPS1, and PAL1. The start of the production of internal volatile compounds in different lines was also determined with a GC-MS. The used transgenic lines of P. hybrida contained ODO1 constructs with either no functional EEs, one functional EE or both functional EEs in the ODO1 promoter region. ODO1 is significantly earlier upregulated in lines with mutations in both EEs, which correlates with earlier production of internal volatiles when compared to wild type P. hybrida. Small changes in the composition of the internal volatiles were also observed.