Project description:We report the application of methylacytosine immunoprecipetation combined with Illumina sequencing (MeDIP-seq) for high-throughput profiling of DNA methylation in rice embryo 3, 6, 9 DAP and endosperm 2, 3, 6, 9 DAP. A total number of 12-14 million of 2×49 bp paired-end reads was generated for each sample, and BOWTIE2 was used for read mapping. We generated genome-wide DNA methylation profiles of rice embryo and endosperm. This study provides a framework to systemically characterize the effect of DNA methylation in developing seeds and will help to illustrate the epigenetic regulation of rice seed development. Rice embryo and endosperm were selected for DNA extraction and methylacytosine immunoprecipetation combined with Illumina sequencing. We sought to obtain the genome-wide DNA methylation profilings of embryo at 3,6,9 days after pollination(DAP) and endosperm at 2,3,6,9 DAP. To that end, we hand-selected embryo at 3,6,9 DAP and endosperm at 2,3,6,9 DAP according to morphological criteria.
Project description:We report the application of methylacytosine immunoprecipetation combined with Illumina sequencing (MeDIP-seq) for high-throughput profiling of DNA methylation in rice embryo 3, 6, 9 DAP and endosperm 2, 3, 6, 9 DAP. A total number of 12-14 million of 2×49 bp paired-end reads was generated for each sample, and BOWTIE2 was used for read mapping. We generated genome-wide DNA methylation profiles of rice embryo and endosperm. This study provides a framework to systemically characterize the effect of DNA methylation in developing seeds and will help to illustrate the epigenetic regulation of rice seed development.
Project description:High-order rice chromatin contains numerous interactions among DNA, RNA and protein to regulate critical biological processes in various aspects of rice life. We developed an effective method for mapping histone-mediated chromatin associated RNA-DNA interactions, followed by paired-end-tag sequencing (ChRD-PET) in rice. With H3K4me3 ChRD-PET, H3 ChRD-PET and RNase H treated H3K4me3 ChRD-PET, we present a highly comprehensive map of RNA and chromatin interactions around promoters in rice MH63. Through integrating ChIA-PET (published data), ChRD-PET and ssDRIP-seq data analysis, we demonstrated the function of RNAs-chromatin interactions in different level. We also conducted ATAC-seq and integrative analysis uncovered the relationship of epigenetic modifications and ChRD-PET interactions. Our findings firstly revealed the map and features of RNAs-chromatin interactions in rice.
Project description:I-motifs (iMs) are non-canonical DNA secondary structures that fold from cytosine (C)-rich genomic DNA regions termed putative i-motif forming sequences (PiMFSs). The structure of iMs is stabilized by hemiprotonated C–C base pairs and their functions are now suspected in key cellular processes in human cells such as genome stability and regulation of gene transcription. In plants, their biological relevance is still largely unknown. Here, we characterized iMs in the rice genome by developing and applying a protocol hinging on an iMab antibody-based immunoprecipitation (IP) coupled with high throughput sequencing (seq), consequently termed iM-IP-seq. We found that PiMFSs had intrinsic subgenomic distributions, cis-regulatory functions and an intricate relationship with DNA methylation. We indeed found that the coordination of PiMFSs with DNA methylation may affect dynamics of transposable elements (TEs) among different cultivated Oryza subpopulations or during evolution of wild rice species. Collectively, our study provides first and unique insights into the biology of iMs in plants, with potential applications in plant biotechnology for improving important agronomic rice traits.
Project description:To summarize the impact of high temperature on rice grain filling, we performed the rice 44k oligo microarray analysis. Total RNA was extracted from developing caryopses ripened under 33ËC/28ËC (high temperature) and 25ËC/20ËC (Control), and subjected to 44k oligo-DNA microarray with 3 biological replicates.
Project description:Anther development, particularly around the time of meiosis, is extremely crucial for plant sexual reproduction. Meanwhile, cell-to-cell communication between somatic (especial tapetum) cells and meiocytes are important for both somatic anther development and meiosis. To investigate possible molecular mechanisms involved in protein activities during anther development, we applied high-resolution mass spectrometry-based proteomic and phosphoproteomic analyses for developing rice (Oryza sativa) anthers around the time of meiosis (RAM). In total, we identified 4,984 proteins and 3,203 phosphoproteins with 8,973 unique phosphorylation sites (p-sites). Among those detected here, 1,544 phosphoproteins are currently absent in the Plant Protein Phosphorylation DataBase (P3DB), substantially enriching plant phosphorylation information. Mapman enrichment analysis showed that “DNA repair”, “transcription regulation” and “signalling” related proteins were over-represented in the phosphorylated proteins. Ten genetically identified rice meiotic proteins were detected to be phosphorylated at a total of 25 p-sites; moreover more than 400 meiotically expressed proteins were revealed to be phosphorylated and their phosphorylation sites were precisely assigned. 163 putative secretory proteins, possibly functioning in cell-to-cell communication, are also phosphorylated. Furthermore, we showed that DNA synthesis, RNA splicing and RNA-directed DNA methylation pathways are extensively affected by phosphorylation. In addition, our data support forty-six kinase-substrate pairs predicted by the rice Kinase-Protein Interaction Map, with SnRK1 substrates highly enriched. Taken together, our data revealed extensive protein phosphorylation during anther development, suggesting an important post-translational modification mechanism for protein activity.