表觀遺傳學(epigenetics)是研究沒有DNA序列變化但引起可遺傳的基因表達改變的學科。表觀遺傳調控方式包括DNA甲基化,組蛋白乙醯化和甲基化,以及染色質重塑等。其中,核心組蛋白的乙醯化修飾在基因的轉錄調控中起到重要的作用。在真核生物中,組蛋白的乙醯化修飾由組蛋白乙醯轉移酶(histone acetyltransferase,HAT)和組蛋白去乙醯化酶(histone deacetylase,HDAC)兩種酶催化。HDACs通過去乙醯化作用移除組蛋白N-末端的乙醯基,引起染色質的鬆散程度降低,從而抑制基因轉錄的起始與表達。
中國科學院華南植物園植物激素信號與表觀遺傳學研究組劉勳成和楊松光博士等在HDACs的生物學功能研究領域取得了一系列研究進展。在植物中,科研人員系統性發現了HDACs通常與轉錄因子及其它染色質調控因子等相互作用,並通過其去乙醯化酶活性抑制基因的表達,從而調控植物開花、葉片發育、種子發育、基因組穩定性及植物光形態建成等生物學過程。
該研究成果已刊登在國際學術期刊Molecular Plant上,論文綜述了植物HDACs的研究進展,重點闡述了HDACs作為轉錄抑制子的作用模式,並對後續植物表觀遺傳學的研究提出了新的見解和展望。華南植物園植物資源保護與可持續利用重點實驗室為論文第一研究單位。 (生物谷Bioon.com)
生物谷推薦的英文摘要:
Mol. Plant doi:0.1093/mp/ssu033
Transcriptional repression by histone deacetylases in plants
Xuncheng Liua,b,1, Songguang Yanga,1, Minglei Zhaoa,c,1, Ming Luoa, Chun-Wei Yub, Chia-Yang Chenb, Ready Taib and Keqiang Wub,2
Reversible histone acetylation and deacetylation at the N-terminus of histone tails play a crucial role in regulation of eukaryotic gene activity. Acetylation of core histones usually induces an 「open」 chromatin structure and is associated with gene activation, whereas deacetylation of histone is often correlated with 「closed」 chromatin and gene repression. Histone deacetylation is catalyzed by histone deacetylases (HDACs). A growing number of studies have demonstrated the importance of histone deacetylation/acetylation on genome stability, transcriptional regulation and development in plants. Furthermore, HDACs were shown to interact with various chromatin remolding factors and transcription factors involved in transcriptional repression in multiple developmental processes. In this review, we summarized recent findings on the transcriptional repression mediated by HDACs in plants.