Convergence of mammalian RQC and C-end rule proteolytic pathways via alanine tailing.
Document Type
Article
Publication Date
5-20-2021
Publication Title
Molecular cell
Keywords
JMG
JAX Source
Mol Cell 2021 May 20; 81(10):2112-2122.e7
Volume
81
Issue
10
First Page
2112
Last Page
2122
ISSN
1097-4164
PMID
33909987
DOI
https://doi.org/10.1016/j.molcel.2021.03.004
Abstract
Incompletely synthesized nascent chains obstructing large ribosomal subunits are targeted for degradation by ribosome-associated quality control (RQC). In bacterial RQC, RqcH marks the nascent chains with C-terminal alanine (Ala) tails that are directly recognized by proteasome-like proteases, whereas in eukaryotes, RqcH orthologs (Rqc2/NEMF [nuclear export mediator factor]) assist the Ltn1/Listerin E3 ligase in nascent chain ubiquitylation. Here, we study RQC-mediated proteolytic targeting of ribosome stalling products in mammalian cells. We show that mammalian NEMF has an additional, Listerin-independent proteolytic role, which, as in bacteria, is mediated by tRNA-Ala binding and Ala tailing. However, in mammalian cells Ala tails signal proteolysis indirectly, through a pathway that recognizes C-terminal degrons; we identify the CRL2
Recommended Citation
Thrun A,
Garzia A,
Kigoshi-Tansho Y,
Patil P,
Umbaugh C,
Dallinger T,
Liu J,
Kreger S,
Patrizi A,
Cox GA,
Tuschl T,
Joazeiro C.
Convergence of mammalian RQC and C-end rule proteolytic pathways via alanine tailing. Mol Cell 2021 May 20; 81(10):2112-2122.e7
Comments
We thank Rick Maser from the JAX Genetic Engineering Technologies group.