表观遗传学可以解释DNA序列不改变而遗传功能改变,环境诱导的表型性状具有可遗传性的问题。介绍了表观遗传学的起源与发展,DNA甲基化(DNA methylation)、组蛋白密码(histone code)、基因组印迹(genomic imprinting)等多种表观遗传机制,并对目前木本植物的表观遗传学研究进行简要综述。由于木本植物自身基因组庞大,许多物种的全基因序列未知等原因,其表观遗传学研究滞后于拟南芥、水稻等草本模式植物。目前,仅杨树(Populus trichocarpa×P.deltoides)、辐射松(Pinus radiateD.Don.)、马占相思(Acacia man-giumWilld.)等树种的基因组DNA甲基化研究取得初步进展,大多数树种尚未开展此部分研究。MSAP等木本植物上可行性技术的广泛应用,将为木本植物的表观遗传研究带来新的契机,并揭示出木本植物所特有的基因调控等表观遗传现象。
Epigenetics can figure out many problems including changes of inheritable function without DNA sequence alteration, heritability of characters induced by surroundings. This article introduces the origin and development of epigenetics, the epigenetic inheritable mechanisms involving DNA methylation, histone code and genomic imprinting. It also briefly summarizes the present epigenetic research in wooden plants. Because the genome of wooden plants is enormous and the background of heredity is complex, the epigenetic research on wooden plants lags the herbaceous model plants, such as Arabidopsis and rice. At present, only the epigenetic research on poplar (Populus trichocarpa x P. deltoides ), radiate pine (Pinus radiate D. Don. ), oil palm (Acacia mangium Willd. )has got some achievements. The extensive applications of MSAP and other technologies will provide new opportunities to epigenetic research on wooden plants,and reveal the specific genetic phenomenon owned by wooden plants.