摘要
DNA甲基化是一类稳定可遗传的表观遗传修饰,在调控基因表达、沉默转座子和维持基因组稳定性等方面发挥重要作用。植物中,DNA从头甲基化通过RNA指导的DNA甲基化(RNA-directedDNAmethylation,RdDM)途径建立。植物特有的DNA依赖的RNA聚合酶Ⅳ(DNA-dependent RNA polymerase Ⅳ, Pol Ⅳ)是RdDM途径核心蛋白,转录产生非编码RNA,通过RdDM途径引导从头建立DNA甲基化,进而调控植物基因表达和生长发育。Pol Ⅳ行使功能受多个蛋白调控:组蛋白阅读器SHH1 (SAWADEE homeodomain homolog 1)识别H3K9甲基化引导Pol Ⅳ到基因组特定位点;染色质重塑因子CLSY (CLASSY)蛋白家族协助Pol Ⅳ识别靶位点;RNA依赖的RNA聚合酶2 (RNA-dependent RNA polymerase 2, RDR2)将Pol Ⅳ转录产生的单链RNA转换成双链RNA。本文总结了Pol Ⅳ及其调控蛋白调控植物DNA甲基化和发育的研究进展,以期为DNA甲基化研究和农作物育种提供参考。
DNA methylation is a type of stable epigenetic modifications that plays crucial roles in regulating gene expression, silencing transposons and maintaining genome stability. In plants, the de novo DNA methylation is established via a pathway termed as RNA-directed DNA methylation(RdDM). The plant-specific DNA-dependent RNA polymerase Ⅳ(Pol Ⅳ) as the core protein in Rd DM pathway produces non-coding RNAs that direct the establishment of DNA methylation, regulates gene expression and controls plant development. Pol Ⅳ function is regulated by several proteins including SHH1, which recognizes H3K9 methylation and guides Pol Ⅳ to genome specific sites, the chromatin remodeling factor CLSY family that is involved in assisting Pol Ⅳ chromatin association and RDR2 that converts Pol Ⅳ produced single-stranded RNA into double-stranded RNA. In this review, we summarize the latest progress on Pol Ⅳ and its co-regulators, and focus on their functions in shaping epigenome and development in plants, which might provide implications for studying of DNA methylation and crop breeding.
作者
许梦萱
周明
Mengxuan Xu;Ming Zhou(Institute of Plant Biology,College of Life Sciences,Zhejiang University,Hangzhou 310058,China)
出处
《遗传》
CAS
CSCD
北大核心
2022年第7期567-580,共14页
Hereditas（Beijing)
基金
中央高校111计划(编号:B14027)
浙江大学“百人计划”资助。
