Department of Biological Sciences, University of Alaska Anchorage, 3211 Providence Dr., Anchorage, AK 99508, USA.
Biochem Cell Biol. 2009 Oct;87(5):767-79. doi: 10.1139/O09-043.
There are a number of well-characterized and fundamental roles for noncoding RNAs (ncRNAs) in gene regulation in all kingdoms of life. ncRNAs, such as ribosomal RNAs, transfer RNAs, small nuclear RNAs, small nucleolar RNAs, and small interfering RNAs, can serve catalytic and scaffolding functions in transcription, messenger RNA processing, translation, and RNA degradation. Recently, our understanding of gene expression has been dramatically challenged by the identification of large and diverse populations of novel ncRNAs in the eukaryotic genomes surveyed thus far. Studies carried out using the budding yeast Saccharomyces cerevisiae indicate that at least some coding genes are regulated by these novel ncRNAs. S. cerevisiae lacks RNA interference (RNAi) and, thus, provides an ideal system for studying the RNAi-independent mechanisms of ncRNA-based gene regulation. The current picture of gene regulation is one of great unknowns, in which the transcriptional environment surrounding a given locus may have as much to do with its regulation as its DNA sequence or local chromatin structure. Drawing on the recent research in S. cerevisiae and other organisms, this review will discuss the identification of ncRNAs, their origins and processing, and several models that incorporate ncRNAs into the regulation of gene expression and chromatin structure.
有许多特征明确且基本的非编码 RNA(ncRNA) 在所有生命领域的基因调控中发挥作用。ncRNA，如核糖体 RNA、转移 RNA、小核 RNA、小核仁 RNA 和小干扰 RNA，可在转录、信使 RNA 加工、翻译和 RNA 降解中发挥催化和支架功能。最近，通过对迄今为止调查的真核生物基因组中新型 ncRNA 的大量和多样化的鉴定，我们对基因表达的理解受到了极大的挑战。使用芽殖酵母酿酒酵母进行的研究表明，至少一些编码基因受到这些新型 ncRNA 的调控。酿酒酵母缺乏 RNA 干扰 (RNAi)，因此，它提供了一个研究基于 ncRNA 的基因调控的 RNAi 独立机制的理想系统。目前的基因调控图景充满了许多未知，给定基因座周围的转录环境可能与其 DNA 序列或局部染色质结构一样对其调控产生影响。本文借鉴了酿酒酵母和其他生物体的最新研究，讨论了 ncRNA 的鉴定、它们的起源和加工，以及将 ncRNA 纳入基因表达和染色质结构调控的几种模型。
