Project description:Illumina RNA Sequencing (RNA-Seq) of Oryza sativa, Nipponbare for the Conserved Poaceae Specific Genes project. Authors: Robin Buell, Ning Jiang, Haining Lin, Rebecca Davidson, Malali Gowda, John Hamilton, Brieanne Vaillancourt
Project description:Cultivated rice (Oryza sativa L.) is frequently exposed to multiple stresses, including Schizotetranychus oryzae mite infestation. Rice domestication has narrowed the genetic diversity of the species, leading to a wide susceptibility. This work aimed to observe the response of two wild rice species (Oryza barthii and O. glaberrima) and two O. sativa genotypes (cv. Nipponbare and f. spontanea) to S. oryzae infestation. Surprisingly, leaf damage, histochemistry, chlorophyll concentration and fluorescence showed that the wild species present higher level of leaf damage, increased accumulation of H2O2 and lower photosynthetic capacity when compared to O. sativa genotypes under infested conditions. Infestation decreased tiller number, except in Nipponbare. Infestation also caused the death of wild plants during the reproductive stage. While infestation did not affect the weight of 1,000 grains in both O. sativa genotypes, the number of panicles per plant was affected only in f. spontanea, and the percentage of full seeds per panicle and seed length were increased only in Nipponbare. Using proteomic analysis, we identified 195 differentially abundant proteins when comparing susceptible (O. barthii) and tolerant (Nipponbare) genotypes under control and infested conditions. O. barthii has a less abundant antioxidant arsenal and is unable to modulate proteins involved with general metabolism and energy production under infested condition. Nipponbare presents high abundance of detoxification-related proteins, general metabolic processes and energy production, suggesting that, under infested condition, the primary metabolism is maintained more active compared to O. barthii. Also, under infested conditions, Nipponbare presents higher levels of proline and a greater abundance of defense-related proteins, such as osmotin, ricin B-like lectin, and protease inhibitors. These differentially abundant proteins can be used as biotechnological tools in breeding programs aiming increased tolerance to mite infestation.
Project description:To better understand the complex mechanisms regulating Pi homeostasis in rice (Oryza sativa L. cv. Nipponbare), a time course experiment was performed, where pre-germinated seedlings were grown hydroponically for two weeks on Pi-sufficient medium (0.32 mM Pi), before transferring half of the plants to Pi-deficient solution (0 mM Pi) for 21 days (d). After three weeks of Pi-starvation treatment, half of these plants where then re-supplied with Pi sufficient media for up to 24 hours (h). In total, nine time points were selected in order to cover short and long term responses to Pi starvation as well as the effects of Pi re-supply on Pi starved plants.