Project description:Here, we present OryzaPG-DB, a rice proteome database based on shotgun proteogenomics, which incorporates the genomic features of experimental shotgun proteomics data. This version of the database was created from the results of 27 nanoLC-MS/MS runs on a hybrid ion trap-orbitrap mass spectrometer, which offers high accuracy for analyzing tryptic digests from undifferentiated cultured rice cells. Peptides were identified by searching the product ion spectra against the protein, cDNA, transcript and genome databases from Michigan State University, and were mapped to the rice genome. Approximately 3200 genes were covered by these peptides and 40 of them contained novel genomic features. Users can search, download or navigate the database per chromosome, gene, protein, cDNA or transcript and download the updated annotations in standard GFF3 format, with visualization in PNG format. In addition, the database scheme of OryzaPG was designed to be generic and can be reused to host similar proteogenomic information for other species. OryzaPG is the first proteogenomics-based database of the rice proteome, providing peptide-based expression profiles, together with the corresponding genomic origin, including the annotation of novelty for each peptide.
Project description:5 leaves old rice plantlets were infected with Magnaporthe grisea spores and zero, two hours and twenty four houres after infection samples were collected
Project description:Iron toxicity is one of the most common mineral disorders affecting Oryza sativa production in flooded lowland fields. Efforts have been made to develop new rice varieties tolerant to Fe toxicity (+Fe). Oryza meridionalis is an endemic from Northern Australia and grows in regions with Fe rich soils, which may provide Fe tolerance genes and mechanisms that can be used for adaptive breeding. Aiming to understand tolerance mechanisms in rice, we screened a population of interspecific introgression lines (IL) from a cross between O. sativa and O. meridionalis for the identification of QTLs contributing to Fe excess tolerance. Six putative QTLs were identified. A line carrying one introgression from O. meridionalis on chromosome 9 associated with one QTL for leaf bronzing score was identified as tolerant in terms of lipid peroxidation and electrolyte leakage despite presenting very high shoot Fe concentrations. Further physiological, biochemical, ionomic and transcriptomic analyses showed that the IL tolerance could be partly explained by Fe partitioning between the leaf sheath and culm. After the in silico construction of an interspecific hybrid genome to map the sequences from transcriptomic analysis, we identified 47 and 27 genes from O. meridionalis up and down-regulated, respectively, by Fe treatment on the tolerant IL. Among possible genes associated with shoot-based tolerance, we identified metallothionein-like proteins, genes from glutathione S-transferase family and transporters from ABC and Major Facilitator Superfamily. This is the first work to demonstrate that introgressions of O. meridionalis in O. sativa genome confer increased tolerance to +Fe
Project description:In the current study, we characterized an miRNA, OsmiR397, which was found to be associated with increased grain size, more rice panicle branching and higher grain productivity. We also elucidated the molecular mechanisms by which OsmiR397 increased grain yield. This miRNA downregulated the expression of its target gene, OsLAC, which then affected the sensitivity of plants to brassinosteroids. These results should be useful for breeding high-yield crops through genetic engineering. We performed RNA-seq on the young panicles of the wild-type, OXmiR397b and OXLAC plants and found that lots of brassinosteroid-related genes were differentially expressed between the three samples
Project description:We characterized a rice (Oryza sativa L ssp. indica cultivar 3037) semi-dwarf mutant sd37, in which CYP96B4 gene (Cytochrome P450 96B subfamily) was identified as the target gene by map-based cloning and complementation test. A point mutation in CYP96B4 leads to a substitution of Thr to Lys in the SRS2 region. The sd37 leaves, panicles and seeds are all smaller compared with those of wild-type, and histological analysis showed that the decreased cell number was the main reason for the dwarf phenotype. We used microarrays to detail the global programme of gene expression underlying cellularisation and identified distinct classes of up- and down- regulated genes during this process.
Project description:LongSAGE library in this series are from 'Whole Genome Analysis of Pathogen-Host Recognition and Subsequent Responses in the Rice Blast Patho-System' project. This work is supported by NSF-PGRP #0115642. Keywords: other
Project description:A rice class I low-molecular-mass heat shock protein (LMM HSP) Oshsp 16.9 was overexpressed in Escherichia coli. Oligomerized complexes of Oshsp16.9 were harvested and electron microscopic observations of purified complexes revealed globular structures of 10-20 nm in diameter (with majority of 15-18 nm) and calculated to comprise approx. 12 monomers per complex. In comparison, complexes from native rice class I LMM HSPs were observed as larger ellipsoid- or globular-like random aggregated hetero-oligomers. To characterize the biochemical functions of the hydrophobic N-terminal region of Oshsp16.9, a truncation in the N-terminal region was constructed and introduced into E. coli. Results showed that the N-terminal truncated Oshsp16.9 mutant was capable of forming complexes similar to the full-length Oshsp16.9; however, the deletion protein failed to confer in vitro protein thermostability under elevated temperatures. Protein assays from in vivo treatments at higher temperatures exhibited that non-specific interactions of E. coli cellular proteins only occurred with full-length Oshsp16.9 complexes but not with the mutant complex. In vitro immunoprecipitation of cellular proteins from E. coli overexpressing full-length Oshsp16.9 showed that interactions between plant LMM HSP and E. coli cellular proteins are temperature-dependent. Taken together, the hydrophobic N-terminal region of rice class I LMM HSP is critical in the ability of the protein to interact/bind with its potential substrates.