Project description:Floral scent serves as a primary mechanism for pollinator attraction, acting as a driver for reproductive isolation and speciation. Because shifts in the composition of floral Volatile Organic Compounds (VOCs) significantly influence a plant's attractiveness, and because the production of these compounds is metabolically costly, plants often reduce scent emissions following successful pollination. This resource-saving strategy is particularly expected in long-lasting fragrant flowers, such as those of the deceptive orchid genus Cypripedium. To investigate potential post-pollination effects on the floral scent of Cypripedium henryi, four pollination treatments were applied to flowers approximately two days post-anthesis (n = 3 replicates per treatment, 12 flowers total): • Treatment P: Removal of both pollinia. • Treatment G: Deposition of a donor flower’s pollinium onto the stigma. • Treatment GP: Simultaneous removal of pollinia and deposition of a donor pollinium. • Treatment K (Control): No artificial manipulation. Floral scent was sampled from each flower immediately before pollination treatment and again 48 hours later. Following the final scent collection, three specific tissue types per flower were harvested for RNA analysis: the labellum, staminode, and lateral petal. The resulting 36 RNA samples were extracted and sequenced to facilitate de novo transcriptome assembly. We quantified transcripts and performed differential expression analysis to compare the pollination treatments against the control group, as well as to identify variation across the different tissue types. Following gene annotation, we focused our investigation on candidate genes within the terpene and fatty acid biosynthesis pathways, which are responsible for producing the characteristic volatiles of C. henryi. Finally, the expression levels of these candidate genes were evaluated in direct relation to the volatile levels identified in the scent analysis to provide a comprehensive view of the molecular regulation of post-pollination scent emission.
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:Rosa chinensis ‘Pallida’ (Rosa L.) is one of the most important ancient rose cultivars originating from China. It contributed the ‘tea scent’ trait to modern roses. However, little information is available on the gene regulatory networks involved in scent biosynthesis and metabolism in Rosa. In this study, the transcriptome of R. chinensis ‘Pallida’ petals at different developmental stages, from flower buds to senescent flowers, was investigated using Illumina sequencing technology. De novo assembly generated 89,614 clusters with an average length of 428 bp. Based on sequence similarity search with known proteins, 62.9% of total clusters were annotated. Out of these annotated transcripts, 25,705 and 37,159 sequences were assigned to gene ontology and clusters of orthologous groups, respectively. The dataset provides information on transcripts putatively associated with known scent metabolic pathways. Digital gene expression (DGE) was obtained using RNA samples from flower bud, open flower and senescent flower stages. Comparative DGE and quantitative real time PCR permitted the identification of five transcripts encoding proteins putatively associated with scent biosynthesis in roses. The study provides a foundation for scent-related genes discovery in roses.
2015-01-01 | GSE54486 | GEO
Project description:The complete chloroplast genome of Clematis florida Thunb., an ornamental plant
Project description:We sequenced mRNA from fertile and sterile flowers growing V. macrocephalum f. keteleeri inflorescence using the Illumina HiSeq2500 platform to generate the first transcriptome dynamics that may serve as a gene expression profile blueprint for sterile and fertile flowers differentiation and development in flowering plant.