Project description:Survey of post pollination events in a sexually deceptive orchid (Ophrys fusca): a transcriptional approach Pollination through deception is a widespread phenomenon in angiosperm, and is extremely common in Orchidaceae family. One of the most striking pollination mechanism in orchids is known as sexual deception, in which flowers lure pollinators by foraging chemical (sex pheromones), visual (e.g. labellum colour and/or shape) and tactile (e.g. labellum pilosity) cues of the female insect pollinator. Ophrys has been used as a model genus to study sexual deception mechanism, mainly regarding chemical analysis in plant-insect association. Study was focused on Ophrys fusca, a species widely distributed in Mediterranean Basin. The main objective rely on Ophrys fusca gene expression study after pollination, through a transcriptional approach using cDNA microarrays. In order to evaluate pollination enhanced events, two different time points were selected: 2 days and 4 days after pollination. Ophrys fusca plants were sampled from a Portuguese natural occurring population. Plants were covered with a white and inert net, built specially for preventing pollinator’s visits in both pollinated and unpollinated flowers. Cross- pollination was performed manually with a sterile plastic stick. Five biological replicates (5 plants in each replicate) from each condition (pollinated and unpollinated) were collected in each time-point Flowers that demonstrate strict pollination regulation, as orchids, provide an excellent model system to unravel pollination- elicited mechanisms (i.e. petal senescence, pigmentation changes, ovary growth). Therefore, this study aims to contribute to the overall knowledge on orchid pollination biology, which is still lacking. 2 time points: 2 days and 4 days after pollination.Two-samples accessed: control (nonpollinated labella) and test (pollinated labella). 5 Biological replicates and 2 technical replicates (repeats of labelling and hybridization using randomly chosen biological replicates) in each time point were made.
Project description:Survey of post pollination events in a sexually deceptive orchid (Ophrys fusca): a transcriptional approach Pollination through deception is a widespread phenomenon in angiosperm, and is extremely common in Orchidaceae family. One of the most striking pollination mechanism in orchids is known as sexual deception, in which flowers lure pollinators by foraging chemical (sex pheromones), visual (e.g. labellum colour and/or shape) and tactile (e.g. labellum pilosity) cues of the female insect pollinator. Ophrys has been used as a model genus to study sexual deception mechanism, mainly regarding chemical analysis in plant-insect association. Study was focused on Ophrys fusca, a species widely distributed in Mediterranean Basin. The main objective rely on Ophrys fusca gene expression study after pollination, through a transcriptional approach using cDNA microarrays. In order to evaluate pollination enhanced events, two different time points were selected: 2 days and 4 days after pollination. Ophrys fusca plants were sampled from a Portuguese natural occurring population. Plants were covered with a white and inert net, built specially for preventing pollinator’s visits in both pollinated and unpollinated flowers. Cross- pollination was performed manually with a sterile plastic stick. Five biological replicates (5 plants in each replicate) from each condition (pollinated and unpollinated) were collected in each time-point Flowers that demonstrate strict pollination regulation, as orchids, provide an excellent model system to unravel pollination- elicited mechanisms (i.e. petal senescence, pigmentation changes, ovary growth). Therefore, this study aims to contribute to the overall knowledge on orchid pollination biology, which is still lacking.
Project description:Analyses of new genomic, transcriptomic or proteomic data commonly result in trashing many unidentified data escaping the ‘canonical’ DNA-RNA-protein scheme. Testing systematic exchanges of nucleotides over long stretches produces inversed RNA pieces (here named “swinger” RNA) differing from their template DNA. These may explain some trashed data. Here analyses of genomic, transcriptomic and proteomic data of the pathogenic Tropheryma whipplei according to canonical genomic, transcriptomic and translational 'rules' resulted in trashing 58.9% of DNA, 37.7% RNA and about 85% of mass spectra (corresponding to peptides). In the trash, we found numerous DNA/RNA fragments compatible with “swinger” polymerization. Genomic sequences covered by «swinger» DNA and RNA are 3X more frequent than expected by chance and explained 12.4 and 20.8% of the rejected DNA and RNA sequences, respectively. As for peptides, several match with “swinger” RNAs, including some chimera, translated from both regular, and «swinger» transcripts, notably for ribosomal RNAs. Congruence of DNA, RNA and peptides resulting from the same swinging process suggest that systematic nucleotide exchanges increase coding potential, and may add to evolutionary diversification of bacterial populations.
2017-12-18 | PXD006238 | Pride
Project description:Genomic characterization of selected edible Benthic species Pachymelania fusca and Pachymelania fusca (quadriseriata)