Project description:Information about protein expression in rice grain across both pigmented and non-pigmented rice varieties is still relatively scarce. The data provided here represent proteomic data obtained from selected 6 Malaysian local rice varieties with varying pigmentations (black, red and white). The selected pigmented rice varieties such as black (BALI and Pulut hitam 9) and red rice (MRQ100 and MRM16) have shown high antioxidant activities and non-pigmented rice (MRQ76 and MR297) contain amino acid and micronutrient contents. This project aimed to obtain global protein expression profile as well as differential protein expression between the selected pigmented and non-pigmented rice varieties particularly proteins with their functions responsible for nutritional (i.e. antioxidant, folate and low glycaemic index) and quality (i.e. aromatic) traits. Integration of this proteomics dataset with other available in-house omics data could facilitate the identification of significant functional markers related to nutritional and quality traits. Total proteins were prepared from dehusked matured seeds harvested from three different rice plants of each variety (3 protein samples per variety). The proteins were trypsin digested before subjected to SWATH-MS proteomics analysis. Proteins were identified by matching tandem mass (MS/MS) spectra from both 1D and 2D IDA to Oryza sativa japonica and indica rice databases available at UniProt by using ProteinPilot software (v4.2) (AB Sciex). Quantification of proteins was carried out by determining protein peak areas extracted from SWATH analysis data sets using PeakView (v2.1) (AB Sciex) software. Differentially expressed protein between varieties were identified using T-test analysis with a set threshold for fold change ± 1.5 and p‐value < 0.05.
Project description:Abstract We have re-analysed publicly available mass spectrometry (MS) data sets enriched for phosphopeptides from Asian rice (Oryza sativa). In total we have identified, 15522 phosphosites on Serine, Threonine and Tyrosine residues on rice proteins. The data has been loaded into UniProtKB, enabling researchers to visualise the sites alongside other stored data on rice proteins, including structural models from AlphaFold2, and into PeptideAtlas, enabling visualisation of the source evidence for each site, including scores and source mass spectra. We identified sequence motifs for phosphosites, and link motifs to enrichment of different biological processes, indicating different downstream regulation caused by different kinase groups. We cross-referenced phosphosites against single amino acid variation (SAAV) data sourced from the rice 3000 genomes data, to identify SAAVs within or proximal to phosphosites that could cause loss of a particular site in a given rice variety. The data was further clustered to identify groups of sites with similar patterns across rice family groups, allowing us to identify sites highly conserved in Japonica, but mostly absent in, for example, Aus type rice varieties - known to have different responses to drought. These resources can assist rice researchers to discover alleles with significantly different functional effects across rice varieties.
Project description:<p>Pigmented rice (<em>Oryza sativa L.</em>) is a rich source of nutrients, but pigmented lines typically have long life cycles and limited productivity. Here we generated genome assemblies of 5 pigmented rice varieties and evaluated the genetic variation among 51 pigmented rice varieties by resequencing an additional 46 varieties. Phylogenetic analyses divided the pigmented varieties into four varietal groups: Geng-japonica, Xian-indica, circum-Aus and circum-Basmati. Metabolomics and ionomics profiling revealed that black rice varieties are rich in aromatic secondary metabolites. We established a regeneration and transformation system and used CRISPR-Cas9 to knock out three flowering time repressors (Hd2, Hd4 and Hd5) in the black Indonesian rice Cempo Ireng, resulting in an early maturing variety with shorter stature. Our study thus provides a multi-omics resource for understanding and improving Asian pigmented rice.</p>
Project description:Copy number variations (CNVs) can create new genes, change gene dosage, reshape gene structures, and modify elements regulating gene expression. As with all types of genetic variation, CNVs may influence phenotypic variation and gene expression. CNVs are thus considered major sources of genetic variation. Little is known, however, about their contribution to genetic variation in rice. To detect CNVs, we used a set of NimbleGen whole-genome comparative genomic hybridization arrays containing 715,851 oligonucleotide probes with a median probe spacing of 500 bp. We compiled a high-resolution map of CNVs in the rice genome, showing 641 CNVs between the genomes of the rice cultivars ‘Nipponbare’ (from O. sativa ssp. japonica) and ‘Guang-lu-ai 4’ (from O. sativa ssp. indica). These CNVs contain some known genes. They are linked to variation among rice varieties, and are likely to contribute to subspecific characteristics.
Project description:Agrobacterium tumefaciens-mediated genetic transformation has been routinely used in rice for more than a decade. However, the transformation efficiency of the indica rice variety is still unsatisfactory and much lower than that of japonica cultivars. Further improvement on the transformation efficiency lies in the genetic manipulation of the plant itself, which requires a better understanding of the underlying process accounting for the susceptibility of plant cells to Agrobacterium infection as well as the identification of plant genes involved in the transformation process. In order to investigate the related genes affecting the transformation efficiency of embryogenic calli of different rice cultivars, we used Affymetrix GeneChipM-BM-. Rice Genome Array to measure the global gene expression profiling just before transformation and at four different time points after transformation (1 h, 6 h, 12 h, 24 h) in both japonica rice cultivar Nipponbare and indica rice cultivar Zhenshan 97. The mature embryo-derived embryogenic calli of Nipponbare (Nip) and Zhenshan 97 (ZS) were infected by Agrobacterium. Calli of Nip and ZS were sampled just before infection (0 h) and 1h, 6h, 12 h and 24h after infection, respectively. Three independent biological replications for each time point of the two varieties were used. To avoid the influence of polymorphisms between the probe sequence on the array and the genomes of the varieties used, we used a genomic DNA (gDNA)-based probe-selection strategy based on the hybridization efficiency of gDNA from Nip and ZS with the PM oligonucleotide probes on the rice array. The genomic DNA of Nip and ZS were extracted and hybridized to the Affymetrix Rice Genome Arrays. Three biological replications per cultivar were performed.
Project description:Hybrid weakness is an important post zygotic reproductive barrier between natural populations. Expression of hybrid weakness can lead to significant decrease in yield and even lethality and is thus an undesirable agronomic trait. We observed that F1 hybrids produced from crossing between any two of three Japonica varieties(CH7, CH8, CH9) exhibit hybrid weakness phenotype. Exploring the molecular mechanism underlying hybrid weakness in important crops like rice is worthy. We used microarrays to obtain a global picture of gene expression changes that occurred in the F1 hybrids with characteristic hybrid weakness phenotype.
Project description:Rice blast is a recurrent fungal disease, and resistance to fungal infection is a complex trait. Therefore, a comprehensive examination of rice transcriptome and its variation during fungal infection is necessary to understand the complex gene regulatory networks. In this study, adopting Next-Generation Sequencing we profiled the transcriptomes and microRNAomes of rice varieties, one susceptible and the other resistant to M. oryzae, at multiple time points during the fungal infection.
Project description:Polyploidization is one of the effective ways to improve plant height and yield of rice (Oryza sativa L.). However, the molecular mechanism of regulation is not yet fully understood. Here, we investigated the agronomic traits of diploid (Balilla-2x) and tetraploid (Balilla-4x) of japonica rice variety Balilla. Compared with Balilla-2x, Balilla-4x exhibited significantly increased plant height, spike length and yield per plant. RNA-seq analysis of the leaves of Balilla-2x and Balilla-4x was performed and the results showed that the expression levels of yield related genes (e.g., STH1, OsYUC9, and OsDEP1) were significantly upregulated in Balilla-4x rice plants, these genes are related to plant height and panicle development. These results indicated that polyploidization changed the expression of genes related to agronomic traits such as plant height and spike length, thereby increasing rice yield. This study provides a further basis for understanding the yield of rice after polyploidization, and can serve as a new theoretical reference for breeding high-yielding rice varieties achieved.
Project description:Improvement of chilling tolerance is a key strategy to face potential menace from abnormal temperature in rice production, which depends on the signaling network triggered by receptors. However, little is known about the QTL genes encoding membrane complexes for sensing cold. Here, Chilling-tolerance in Gengdao/japonica rice 1 (COG1) was isolated from a chromosome segment substitution line containing a QTL (qCS11-jap) for chilling sensitivity. The major gene COG1 was found to confer chilling tolerance in japonica rice. In natural rice populations, only the haplogroup1 encoded a functional COG1. Evolutionary analysis showed that COG1 originated from Chinese O. Rufipogon and was fixed in japonica rice during domestication. COG1, a membrane-localized LRR-RLP, targeted and activated the kinase OsSERL2 in a cold-induced manner, promoting chilling tolerance. Furthermore, the cold signal transmitted by COG1-OsSERL2 activates OsMAPK3 in the cytoplasm. Our findings reveal a cold-sensing complex, which mediates signaling network for the chilling defense in rice.