Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA; email:
Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA.
Annu Rev Microbiol. 2018 Sep 8;72:255-271. doi: 10.1146/annurev-micro-090817-062814.
RNA localization mechanisms have been intensively studied and include localized protection of mRNA from degradation, diffusion-coupled local entrapment of mRNA, and directed transport of mRNAs along the cytoskeleton. While it is well understood how cells utilize these three mechanisms to organize mRNAs within the cytoplasm, a newly appreciated mechanism of RNA localization has emerged in recent years in which mRNAs phase-separate and form liquid-like droplets. mRNAs both contribute to condensation of proteins into liquid-like structures and are themselves regulated by being incorporated into membraneless organelles. This ability to condense into droplets is in many instances contributing to previously appreciated mRNA localization phenomena. Here we review how phase separation enables mRNAs to selectively and efficiently colocalize and be coregulated, allowing control of gene expression in time and space.
RNA 定位机制已得到深入研究，包括 mRNA 的局部保护免受降解、扩散偶联的 mRNA 局部捕获以及沿着细胞骨架的定向运输。尽管人们已经很好地理解了细胞如何利用这三种机制在细胞质中组织 mRNA，但近年来出现了一种新的 RNA 定位机制，即 mRNA 相分离并形成类似液体的液滴。mRNA 既有助于将蛋白质浓缩成类似液体的结构，又通过被纳入无膜细胞器而受到调节。这种凝聚成液滴的能力在许多情况下有助于解释先前已被认识到的 mRNA 定位现象。在这里，我们回顾了相分离如何使 mRNA 能够选择性和有效地共定位和共调节，从而实现时间和空间上的基因表达控制。
