Project description:DNA methylation is an important epigenetic modification that regulates various plant developmental processes. Rice seed integument determines the seed size. However, the role of DNA methylation in its development remains largely unknown. Here, we report the first dynamic DNA methylomic profiling of rice maternal integument before and after pollination by using a whole-genome bisulfite deep sequencing approach. Analysis of DNA methylation patterns identified 4238 differentially methylated regions underpin 4112 differentially methylated genes, including GW2, DEP1, RGB1 and numerous other regulators participated in maternal integument development. Bisulfite sanger sequencing and qRT-PCR of six differentially methylated genes revealed extensive occurrence of DNA hypomethylation triggered by double fertilization at IAP compared with IBP, suggesting that DNA demethylation might be a key mechanism to activate numerous maternal controlling genes. These results presented here not only greatly expanded the rice methylome dataset, but also shed novel insight into the regulatory roles of DNA methylation in rice seed maternal integument development.
Project description:Purpose: The goal of our study is to compare two different ecotypes of Oryza sativa L., PHS-susceptible rice trait and PHS-resistant rice trait under three different maturation stages in rice seed embryo with profile of miRNA-seq. Methods: Oryza sativa. L miRNA profiles of two different ecotypes with 3 different maturation stages of rice seed embryo were generated by NGS, in duplicate, following Illumina NGS workflow. Results: We found the differentially expressed microRNAs between PHS-susceptible rice trait and PHS-resistant rice trait according to the three different seed maturation stages. Target transcripts of differentially expressed microRNAs have been predicted via psRNATarget web server, and a part of those target genes are likely to be regulated by microRNAs, affecting overall responses to heat stress and the regulation of seed dormancy during maturation. Conclusions: Our study represents the analysis of rice seed small RNAs, specifically microRNAs, under two different ecotypes, three different seed maturation stages in rice seed embryo. Our results show that microRNAs are involved in response to heat stress and the regulation of seed dormancy. This study will provide a foundation for understanding dynamics of seed dormancy during the seed development and overcoming pre-harvest sprouting.
Project description:Purpose: The goal of our study is to compare two different ecotypes of Oryza sativa L., PHS-susceptible rice trait and PHS-resistant rice trait under three different maturation stages and two different tissues, embryo and endosperm of rice seeds with profile of RNA-seq. Methods: Oryza sativa. L mRNA profiles of two different ecotypes with 3 different maturation stages and 2 different tissues were generated by NGS, in duplicate, following Illumina NGS workflow. qRT–PCR validation was performed using SYBR Green assays. Results: We found the differentially expressed genes (DEGs) between PHS-susceptible rice trait and PHS-resistant rice trait according to the three different seed maturation stages. In DEGs, gene ontology (GO) analysis and Mapman analysis were performed, and we discovered genes related to plant hormones and heat stress, which are not yet reported. These genes were validated through qRT-PCR, and it is likely to be highly related to seed dormancy. Conclusions: Our study represents the analysis of rice seed transcriptomes under two different ecotypes, three different seed maturation stages and two different tissues (Embryo and endosperm). Our results show that seed dormancy is affected and regulated by a plant hormones and heat stress. This study might provide a foundation for understanding dynamics of seed dormancy during the seed development and overcoming pre-harvest sprouting.
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:Lysine acetylation is a dynamic and reversible post-translational modification that plays an imporant role in the gene transcription regulation. Here, we report high quality proteome-scale data for lysine-acetylation sites and proteins in rice (Oryza sativa). A total of 1337 Kac sites in 716 Kac proteins with diverse biological functions and subcellular localizations were identified in rice seedlings.
Project description:MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) regulate gene expression in eukaryotes. Plant miRNAs modulate their targets mainly via messenger RNA (mRNA) cleavage. Small RNA targets have been extensively investigated in Arabidopsis using computational prediction, experimental validation, and degradome sequencing. However, small RNA targets are largely unknown in rice (Oryza sativa). Here, we report global identification of small RNA targets using high throughput degradome sequencing in the rice indica cultivar 93-11 (Oryza sativa L. ssp. indica). 177 transcripts targeted by total of 87 unique miRNAs were identified. Of targets for the conserved miRNAs between Arabidopsis and rice, transcription factors comprise around 70% (58 in 82), indicating that these miRNAs act as masters of gene regulatory nodes in rice. In contrast, non-conserved miRNAs targeted diverse genes which provide more complex regulatory networks. In addition, 5 AUXIN RESPONSE FACTORS (ARF) cleaved by the TAS3 derived ta-siRNAs were also detected. A total of 40 sRNA targets were further validated via RNA ligase-mediated 5M-bM-^@M-^Y rapid amplification of cDNA ends (RLM 5M-bM-^@M-^Y-RACE). Our degradome results present a detailed sRNA-target interaction atlas, which provides a guide for the study of the roles of sRNAs and their targets in rice. The degradome sequence of Young inflorescences from Oryza sativa L. ssp. indica (93-11) was sequenced
Project description:MicroRNAs (miRNAs) play important roles in various aspects of plant physiology and metabolism. The expression level of miR164c is negatively correlated with seed vigor in rice (Oryza sativa L.); however, the mechanism of seed vigor regulation by miR164c remains unknown. Here, we studied the proteomic difference between seeds of the wild-type rice cultivar ‘Kasalath’ and its transgenic derivatives, miR164c-silenced line (MIM164c) and miR164c overexpression line (OE164c), with significant differences in anti-aging capacity. We hope that it can provide new insights into the mechanism of miRNA on regulating seed vigor.
Project description:MicroRNAs (miRNAs) play important roles in various aspects of plant physiology and metabolism. The expression level of miR164c is negatively correlated with seed vigor in rice (Oryza sativa L.); however, the mechanism of seed vigor regulation by miR164c remains unknown. Here, we studied the proteomic difference between artificially aged seeds of the wild-type rice cultivar ‘Kasalath’ and its transgenic derivatives, miR164c-silenced line (MIM164c) and miR164c overexpression line (OE164c), with significant differences in anti-aging capacity. We hope that it can provide new insights into the mechanism of miRNA on regulating seed vigor.
Project description:MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) regulate gene expression in eukaryotes. Plant miRNAs modulate their targets mainly via messenger RNA (mRNA) cleavage. Small RNA targets have been extensively investigated in Arabidopsis using computational prediction, experimental validation, and degradome sequencing. However, small RNA targets are largely unknown in rice (Oryza sativa). Here, we report global identification of small RNA targets using high throughput degradome sequencing in the rice indica cultivar 93-11 (Oryza sativa L. ssp. indica). 177 transcripts targeted by total of 87 unique miRNAs were identified. Of targets for the conserved miRNAs between Arabidopsis and rice, transcription factors comprise around 70% (58 in 82), indicating that these miRNAs act as masters of gene regulatory nodes in rice. In contrast, non-conserved miRNAs targeted diverse genes which provide more complex regulatory networks. In addition, 5 AUXIN RESPONSE FACTORS (ARF) cleaved by the TAS3 derived ta-siRNAs were also detected. A total of 40 sRNA targets were further validated via RNA ligase-mediated 5’ rapid amplification of cDNA ends (RLM 5’-RACE). Our degradome results present a detailed sRNA-target interaction atlas, which provides a guide for the study of the roles of sRNAs and their targets in rice.
Project description:The R-loop is a common chromatin feature presented from prokaryotic to eukaryotic genomes and has been revealed to be involved in multiple cellular processes and associated with many human diseases. Here, we take the advantage of our recently developed ssDRIP-seq method to profile genome-wide R-loop levels and provided a first-hand R-loop atlas of Rice (Oryza sativa) at different developmental stages.