LMGM, Université de Toulouse, CNRS, UPS, CBI, Toulouse, France; email:
TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France.
Annu Rev Microbiol. 2022 Sep 8;76:533-552. doi: 10.1146/annurev-micro-041020-113308. Epub 2022 Jun 7.
RNA degradosomes are multienzyme complexes composed of ribonucleases, RNA helicases, and metabolic enzymes. RNase E-based degradosomes are widespread in . The RNA degradosome is sequestered from transcription in the nucleoid and translation in the cytoplasm by localization to the inner cytoplasmic membrane, where it forms short-lived clusters that are proposed to be sites of mRNA degradation. In , RNA degradosomes localize to ribonucleoprotein condensates in the interior of the cell [bacterial ribonucleoprotein-bodies (BR-bodies)], which have been proposed to drive the concerted degradation of mRNA to nucleotides. The turnover of mRNA in growing cells is important for maintaining pools of nucleotides for transcription and DNA replication.Membrane attachment of the RNA degradosome is necessary to avoid wasteful degradation of intermediates in ribosome assembly. Sequestering RNA degradosomes to BR-bodies, which exclude structured RNA, could have a similar role in protecting intermediates in ribosome assembly from degradation.
RNA 降解体是由核糖核酸酶、RNA 解旋酶和代谢酶组成的多酶复合物。基于 RNase E 的降解体在 中广泛存在。RNA 降解体通过定位于细胞质内膜而与核仁中的转录和细胞质中的翻译隔离，在那里形成短暂的聚集体，这些聚集体被提议为 mRNA 降解的部位。在 中，RNA 降解体定位于细胞内部的核糖核蛋白凝聚体（细菌核糖核蛋白体（BR 体））中，这些凝聚体被提议促进 mRNA 的协同降解为核苷酸。生长细胞中 mRNA 的周转率对于维持转录和 DNA 复制所需的核苷酸池很重要。 RNA 降解体的膜附着对于避免核糖体组装过程中中间产物的浪费降解是必要的。将 RNA 降解体隔离到 BR 体中，该体排除结构 RNA，可能在保护核糖体组装过程中的中间产物免受降解方面发挥类似作用。
