BIO5 Institute, University of Arizona, Tucson, 85721, United States.
Curr Opin Genet Dev. 2010 Apr;20(2):156-63. doi: 10.1016/j.gde.2010.01.008. Epub 2010 Feb 12.
Paramutation involves trans-interactions between alleles or homologous sequences that establish distinct gene expression states that are heritable for generations. It was first described in maize by Alexander Brink in the 1950s, with his studies of the red1 (r1) locus. Since that time, paramutation-like phenomena have been reported in other maize genes, other plants, fungi, and animals. Paramutation can occur between endogenous genes, two transgenes or an endogenous gene, and transgene. Recent results indicate that paramutation involves RNA-mediated heritable chromatin changes and a number of genes implicated in RNAi pathways. However, not all aspects of paramutation can be explained by known mechanisms of RNAi-mediated transcriptional silencing.
顺式调控涉及等位基因或同源序列之间的相互作用，这些作用建立了可遗传的不同基因表达状态，这种现象可以持续几代。20 世纪 50 年代，Alexander Brink 在对玉米 red1（r1）基因座的研究中首次描述了这种现象。从那时起，在其他玉米基因、其他植物、真菌和动物中也报道了类似顺式调控的现象。顺式调控可以发生在内源性基因、两个转基因或一个内源性基因和转基因之间。最近的研究结果表明，顺式调控涉及 RNA 介导的可遗传染色质变化，以及一些涉及 RNAi 途径的基因。然而，并非顺式调控的所有方面都可以用已知的 RNAi 介导的转录沉默机制来解释。
