Rice melatonin deficiency causes premature leaf senescence via DNA methylation regulation
Yue Lu, Ahmed Gharib, Rujia Chen, Hanyao Wang, Tianyun Tao, Zhihao Zuo, Qing Bu, Yanze Su, Yaoqing Li, Yanmo Luo, Hamdi F. El-Mowafi, Zhichao Wang, Qianfeng Huang, Shuting Wang, Yang Xu, Pengcheng Li, Chenwu Xu, Zefeng Yang
Abstract
In a study of DNA methylation changes in melatonin-deficient rice mutants, mutant plants showed premature leaf senescence during grain-filling and reduced grain yield. Melatonin deficiency led to transcriptional reprogramming, especially of genes involved in chlorophyll and carbon metabolism, redox regulation, and transcriptional regulation, during dark-induced leaf senescence. Hypomethylation of mCG and mCHG in the melatonin-deficient rice mutants was associated with the expression change of both protein-coding genes and transposable element-related genes. Changes in gene expression and DNA methylation in the melatonin-deficient mutants were compensated by exogenous application of melatonin. A decreased S-adenosyl-L-methionine level may have contributed to the DNA methylation variations in rice mutants of melatonin deficiency under dark conditions.