Fishman Elizabeth S, Han Jisoo S, La Torre Anna
Department of Cell Biology and Human Anatomy, University of California, Davis, Davis, CA, United States.
Front Cell Dev Biol. 2022 Feb 2;10:831750. doi: 10.3389/fcell.2022.831750. eCollection 2022.
A broad repertoire of transcription factors and other genes display oscillatory patterns of expression, typically ranging from 30 min to 24 h. These oscillations are associated with a variety of biological processes, including the circadian cycle, somite segmentation, cell cycle, and metabolism. These rhythmic behaviors are often prompted by transcriptional feedback loops in which transcriptional activities are inhibited by their corresponding gene target products. Oscillatory transcriptional patterns have been proposed as a mechanism to drive biological clocks, the molecular machinery that transforms temporal information into accurate spatial patterning during development. Notably, several microRNAs (miRNAs) -small non-coding RNA molecules-have been recently shown to both exhibit rhythmic expression patterns and regulate oscillatory activities. Here, we discuss some of these new findings in the context of the developing retina. We propose that miRNA oscillations are a powerful mechanism to coordinate signaling pathways and gene expression, and that addressing the dynamic interplay between miRNA expression and their target genes could be key for a more complete understanding of many developmental processes.
大量的转录因子和其他基因呈现出振荡性的表达模式，其周期通常在30分钟到24小时之间。这些振荡与多种生物过程相关，包括昼夜节律周期、体节分割、细胞周期和新陈代谢。这些节律性行为通常由转录反馈环引发，在转录反馈环中，转录活动受到其相应基因靶标产物的抑制。振荡性转录模式已被提出作为驱动生物钟的一种机制，生物钟是在发育过程中将时间信息转化为精确空间模式的分子机制。值得注意的是，最近有研究表明，几种微小RNA（miRNA）——小的非编码RNA分子——既表现出节律性表达模式，又能调节振荡活动。在这里，我们将在视网膜发育的背景下讨论其中的一些新发现。我们认为，miRNA振荡是协调信号通路和基因表达的一种强大机制，解决miRNA表达与其靶基因之间的动态相互作用可能是更全面理解许多发育过程关键所在。
