小柯机器人

美国约翰霍普金斯大学Allen R. Buskirk、德国慕尼黑大学Roland Beckmann等研究人员合作发现，核糖体碰撞在细菌中引起mRNA切割和核糖体拯救。2022年3月9日，《自然》杂志在线发表了这项成果。

据研究人员介绍，核糖体拯救途径对停滞的核糖体进行回收，并针对有问题的mRNA和中止的蛋白质进行降解。在细菌中，目前仍不清楚救援途径如何区分停滞在转录本中间的核糖体和积极翻译的核糖体。

Title: Ribosome collisions induce mRNA cleavage and ribosome rescue in bacteria

Author: Saito, Kazuki, Kratzat, Hanna, Campbell, Annabelle, Buschauer, Robert, Burroughs, A. Maxwell, Berninghausen, Otto, Aravind, L., Green, Rachel, Beckmann, Roland, Buskirk, Allen R.

Issue&Volume: 2022-03-09

Abstract: Ribosome rescue pathways recycle stalled ribosomes and target problematic mRNAs and aborted proteins for degradation1,2. In bacteria, it remains unclear how rescue pathways distinguish ribosomes stalled in the middle of a transcript from actively translating ribosomes3,4,5,6. Here, using a genetic screen in Escherichia coli, we discovered a new rescue factor that has endonuclease activity. SmrB cleaves mRNAs upstream of stalled ribosomes, allowing the ribosome rescue factor tmRNA (which acts on truncated mRNAs3) to rescue upstream ribosomes. SmrB is recruited to ribosomes and is activated by collisions. Cryo-electron microscopy structures of collided disomes from E. coli and Bacillus subtilis show distinct and conserved arrangements of individual ribosomes and the composite SmrB-binding site. These findings reveal the underlying mechanisms by which ribosome collisions trigger ribosome rescue in bacteria.

DOI: 10.1038/s41586-022-04416-7

Source: https://www.nature.com/articles/s41586-022-04416-7

Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html