植物转基因沉默

Gene Silencing of Trans-gene Plant

转基因沉默分为两种水平:第一种是转录水平上的基因沉默,发生原因主要是位置效应、异染色质化以及甲基化;第二种是转录后水平上的基因沉默,发生原因是通过对靶标RNA进行特异性降解而使基因失活,并就此研究提出RNA阈值模型、异常RAN模型、分子间(内)配对模型与RNA干涉模型来解释这种现象产生的机制。

There are two kinds of gene silencing phenomena.One is called transcriptional gene silencing which is mainly caused by position effect and DNA′s methylation and heterochromatinization.The other is the post-transcriptional gene silencing caused by the devastation of RNA,and four modeles to explain the mechanism are given in this paper.