Project description:Protein post-translational modification (PTM) increases the functional diversity of the proteome and regulates numerous biological processes in eukaryotes. Two types of PTMs, O-linked-acetyl glucosamine modification (O-GlcNAc) and phosphorylation have been identified on the same amino acid, are considered as Yin-Yang modification for their antagonistic function recently. Vernalization, a prolonged cold exposure promoted flowering, is important for grain yield in temperate cereals, such as winter wheat. O-GlcNAcylation on TaGRP2 and phosphorylation on VER2 are involved in regulation of vernalization response (VRN) genes. However, less is known about how plant senses vernalization with general Yin-Yang modifications. Here we report that altering O-GlcNAc signaling by chemical inhibitors could change the vernalization response and affect flowering transition. Furthermore, we enriched O-GlcNAcylated and phosphorylated peptides from winter wheat plumules at different processing time points during vernalization by Lectin weak affinity chromatography (LWAC) and iTRAQ-TiO2, respectively. In total, about 200 O-GlcNAcylated proteins and 124 differential expressed phosphorylated proteins were identified by Mass Spectrum (MS). Based on GO enrichment, the identified O-GlcNAcylated proteins are mainly involved in response to abiotic stimulus and hormone, metabolic processing and gene expression. While dynamic phosphorylated proteins during vernalization participate in translation, transcription and metabolic processing. Of note, 31 proteins with both phosphorylation and O-GlcNAcylation modification were identified. Among them, TaGRP2 was further confirmed to participate in regulation of vernalization promoted flowering. The global modification profiles and genetic data at specific regulator suggested that the dynamic network of O-GlcNAcylation and phosphorylation on the key nodes regulate vernalization response and mediate flowering in wheat.
Project description:Protein post-translational modification (PTM) increases the functional diversity of the proteome and regulates numerous biological processes in eukaryotes. Two types of PTMs, O-linked-acetyl glucosamine modification (O-GlcNAc) and phosphorylation have been identified on the same amino acid, are considered as Yin-Yang modification for their antagonistic function recently. Vernalization, a prolonged cold exposure promoted flowering, is important for grain yield in temperate cereals, such as winter wheat. O-GlcNAcylation on TaGRP2 and phosphorylation on VER2 are involved in regulation of vernalization response (VRN) genes. However, less is known about how plant senses vernalization with general Yin-Yang modifications. Here we report that altering O-GlcNAc signaling by chemical inhibitors could change the vernalization response and affect flowering transition. Furthermore, we enriched O-GlcNAcylated and phosphorylated peptides from winter wheat plumules at different processing time points during vernalization by Lectin weak affinity chromatography (LWAC) and iTRAQ-TiO2, respectively. In total, about 200 O-GlcNAcylated proteins and 124 differential expressed phosphorylated proteins were identified by Mass Spectrum (MS). Based on GO enrichment, the identified O-GlcNAcylated proteins are mainly involved in response to abiotic stimulus and hormone, metabolic processing and gene expression. While dynamic phosphorylated proteins during vernalization participate in translation, transcription and metabolic processing. Of note, 31 proteins with both phosphorylation and O-GlcNAcylation modification were identified. Among them, TaGRP2 was further confirmed to participate in regulation of vernalization promoted flowering. The global modification profiles and genetic data at specific regulator suggested that the dynamic network of O-GlcNAcylation and phosphorylation on the key nodes regulate vernalization response and mediate flowering in wheat.
Project description:We conducted genome-wide transcriptome analysis using the inbred Chinese cabbage line, ‘4004’, which displayed early flowering in response to vernalization. A total of 1,677 differentially-expressed genes (DEGs) were identified with and without vernalization. Transcriptome analysis identified 223 homologs of Arabidopsis Ft genes in Chinese cabbage, and 50 of these genes responded to vernalization. RT-qPCR analysis of major Ft genes showed that the majority of flowering enhancers were up-regulated in response to vernalization, whereas most flowering repressors were down-regulated in response to vernalization. Among the major Ft genes, the expression of BrCOL1-2, BrFT1/2, BrSOC1/2/3, BrFLC1/2/3/5, and BrMAF was strongly affected by vernalization.
Project description:Falster is a Danish perennial ryegrass ecotype with strong vernalization requirement, while Veyo is an Italian variety with no requirement for vernalization in order to flower. The transcriptome of these two perennial ryegrass genotypes with contrasting vernalization requirements was studied during primary (vernalization and short day conditions), and secondary induction (higher temperature and long day conditions) using an RNA-Seq approach, in order to reveal transcripts with expression profiles indicative of a role in floral induction, both in the promotion and repression of flowering.
Project description:In order to find out the key proteins in flowering time, proteomic analysis was carried out on the early-flowering and later-flowering orchardgrass at different development stages. Subsequently, the key genes related to proteins in flowering time of orchardgrass were identified and verified by co-analysis with other omics.
Project description:The transition from vegetative growth to reproductive growth involves many pathways. Vernalization is crucial to the formation of floral organs, the regulation of flowering time and plant breeding. The purpose of this study was to identify the mRNA, microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA) related to vernalization of Chinese cabbage, and to construct a competitive endogenous RNA (ceRNA) network, so as to provide valuable information for exploring the molecular mechanism of vernalization of Chinese cabbage. Results: The results of whole-transcriptome sequencing showed that 2702 mRNAs, 151 lncRNAs, 16 circRNA, and 233 miRNAs were differentially expressed in vernalized (‘Ver’) and non-vernalized (‘Nor’) seeds of Chinese cabbage. Some transcription factors and regulatory proteins that play important roles in vernalization pathway have been identified, such as the transcription factors of WRKY, MYB, NAC, bHLH, and MADS-box, zinc finger protein CONSTANS like gene and B3 domain protein. We constructed vernalization-related ceRNA-miRNA-target gene network and obtained 199 pairs of ceRNA relationships, including 108 DEmiRNA-DEmRNA, 67 DEmiRNA-DElncRNA, and 12 DEmiRNA-DEcircRNA interactions in Chinese cabbage. Meanwhile, several important vernalization-related genes and their interacting lncRNAs, circRNAs, and miRNAs were identified, which were involved in the regulation of flowering time, floral organ formation, bolting and flowering. Conclusions: The candidate differentially expressed mRNA, miRNA, lncRNA and circRNA for vernalization of Chinese cabbage were identified by the whole-transcriptome sequencing, and the ceRNA network was constructed. This study laid a foundation for further study on the molecular mechanism of vernalization in Chinese cabbage.
Project description:Vernalization, the requirement of long-term exposure to low environmental temperature for flowering, is a typical epigenetic phenomenon in plants. Histone modifications have been analyzed for key vernalization genes, but genome-wide regulation remains unclear. Here, we performed global analysis of histone 3 lysine 4 (H3K4me3) and 27 (H3K27me3) trimethylation with Chromatin Immunoprecipitation-Sequencing (ChIP-Seq) during and after vernalization to obtain complete view of histone modification fluctuation both on whole genome scale and for single genes, even different regions of genes. The critical role of H3K27me3 was revealed. During vernalization H3K27me3 regulation concentrated on a few biological processes, with two essential environmental responses, transcription regulation and anti-stress reactions, being main targets, as indicated by change pattern and GO analysis. The regulation of H3K4me3, however, showed no obvious focus. For gene expression, H3K27me3 is involved in multiple trends of control. H3K4me3, however, mainly focuses on unidirectional regulation. After vernalization most of H3K27me3 changes were kept, but relatively small proportion of H3K4me3 changes could be maintained, as shown by multiple-level analysis, suggesting the active role of H3K27me3 in epigenetic memory. Vernalization-induced histone modification changes were uncovered for VRN3, a gene integrating vernalization/photoperiod signals, suggesting its regulation role at epigenetic level. Memory-related genes were genome-widely identified and a high proportion of them showed quantitative response to vernalization-treatment, suggesting broad existence of this mechanism. Our studies shed new light on epigenetic role of H3K27me3 and VRN3 in vernalization, revealed mechanism underlying epigenetic memory, which helps us to further understand vernalization, a mechanism with great potential in agriculture.