DNA hypermethylation promotes the flowering of orchardgrass during vernalization

DOI:10.1093/plphys/kiac335

发表期刊：Plant Physiology

链接：https://academic.oup.com/plphys/advance-article/doi/10.1093/plphys/kiac335/6647858

Zhongfu Yang¹, Haidong Yan¹, Jianping Wang, Gang Nie, Guangyan Feng, Xiaoheng Xu, Dandan Li, Linkai Huang*, Xinquan Zhang*

Abstract：Vernalization, influenced by environmental factors, is an essential process associated with the productivity of temperate crops, during which epigenetic regulation of gene expression plays an important role. Although DNA methylation is one of the major epigenetic mechanisms associated with the control of gene expression, global changes in DNA methylation in the regulation of gene expression during vernalization-induced flowering of temperate plants remain largely undetermined. To characterize vernalization-associated DNA methylation dynamics, we performed whole-genome bisulphite-treated sequencing and transcriptome sequencing in orchardgrass (Dactylis glomerata) during vernalization. The results revealed that increased levels of genome DNA methylation during early vernalization of orchardgrass were associated with transcriptional changes in DNA methyltransferase and demethylase genes. Up-regulated expression of vernalization-related genes during early vernalization was attributable to an increase in mCHH in the promoter regions of these genes. Application of an exogenous DNA methylation accelerator or overexpression of orchardgrassNUCLEAR POLY(A) POLYMERASE(DgPAPS4) promoted earlier flowering, indicating that DNA hypermethylation plays an important role in vernalization-induced flowering. Collectively, our findings revealed that vernalization-induced hypermethylation is responsible for floral primordium initiation and development. These observations provide a theoretical foundation for further studies on the molecular mechanisms u