Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Graduate Program in Molecular Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
Dev Cell. 2013 Oct 28;27(2):161-173. doi: 10.1016/j.devcel.2013.09.024.
Like membranous organelles, large-scale coassembly of macromolecules can organize functions in cells. Ribonucleoproteins (RNPs) can form liquid or solid aggregates, but control and consequences of these RNP states in living, developing tissue are poorly understood. Here, we show that regulated RNP factor interactions drive transitions among diffuse, semiliquid, or solid states to modulate RNP sorting and exchange in the Caenorhabditis elegans oocyte cytoplasm. Translation repressors induce an intrinsic capacity of RNP components to coassemble into either large semiliquids or solid lattices, whereas a conserved RNA helicase prevents polymerization into nondynamic solids. Developmental cues dramatically alter both fluidity and sorting within large RNP assemblies, inducing a transition from RNP segregation in quiescent oocytes to dynamic exchange in the early embryo. Therefore, large-scale organization of gene expression extends to the cytoplasm, where regulation of supramolecular states imparts specific patterns of RNP dynamics.
类似于膜细胞器，大分子的大规模共组装可以在细胞中组织功能。核糖核蛋白（RNP）可以形成液体或固体聚集体，但在活体、发育组织中对这些 RNP 状态的控制和后果知之甚少。在这里，我们表明，受调控的 RNP 因子相互作用驱动 RNP 在扩散、半液体或固体状态之间的转变，从而调节秀丽隐杆线虫卵母细胞质中的 RNP 分选和交换。翻译抑制剂诱导 RNP 成分内在地共组装成大的半液体或固体晶格，而保守的 RNA 解旋酶阻止聚合为非动态固体。发育线索极大地改变了大的 RNP 组装体的流动性和分选，诱导从静止卵母细胞中的 RNP 分离到早期胚胎中的动态交换的转变。因此，基因表达的大规模组织扩展到细胞质，其中超分子状态的调节赋予 RNP 动力学的特定模式。
