变位现象：一种跨同源物相互作用，影响可遗传的基因调控。

Paramutation: a trans-homolog interaction affecting heritable gene regulation.

机构信息

Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA.

出版信息

Curr Opin Plant Biol. 2012 Nov;15(5):536-43. doi: 10.1016/j.pbi.2012.09.003. Epub 2012 Sep 24.

DOI:10.1016/j.pbi.2012.09.003

Abstract

Paramutation describes both the process and results of trans-sensing between chromosomes that causes specific heritable changes in gene regulation. RNA molecules are implicated in mediating similar events in maize, mouse, and Drosophila. Changes in both small RNA profiles and cytosine methylation patterns in Arabidopsis hybrids represent a potential molecular equivalent to the interactions responsible for paramutations. Despite a seemingly unifying feature of RNA-directed changes, both recent and historical works show that paramutations in maize require plant-specific proteins and lack expected hallmarks of a trans-effect mediated solely by RNAs. Recent examples of nearby transposons affecting RNA polymerase II functions lead to an opinion that paramutations represent an emergent property of the transcriptional dynamics ongoing in plant genomes between repetitious features and nearby genes.

摘要

拟突变描述了染色体之间的跨感应过程和结果，导致基因调控的特定可遗传变化。RNA 分子被牵连到玉米、老鼠和果蝇中类似事件的调解中。拟突变在拟南芥杂种中改变小 RNA 谱和胞嘧啶甲基化模式，代表了与负责拟突变的相互作用的潜在分子等效物。尽管 RNA 定向变化具有看似统一的特征，但最近和历史上的工作表明，玉米中的拟突变需要植物特异性蛋白，并且缺乏仅由 RNA 介导的转效的预期特征。最近的例子表明，附近的转座子影响 RNA 聚合酶 II 的功能，这导致一种观点认为，拟突变代表了植物基因组中重复特征和附近基因之间正在进行的转录动态的新兴特性。