反应性醛是丰富的内源性代谢物，通过交联细胞大分子来挑战体内平衡。醛诱导的 DNA 损伤需要修复以预防癌症和过早衰老，但尚不清楚细胞是否也具有解决醛诱导的 RNA 损伤的机制。在这里，我们建立了光活化核糖核苷增强交联（PAR-CL）作为模型系统，用于研究人类细胞中不存在混杂 DNA 损伤的情况下的 RNA 交联损伤。我们发现这种RNA损伤通过阻止核糖体的延伸而引起翻译应激，从而导致与尾随核糖体的碰撞并激活多种应激反应途径。此外，我们发现了一种翻译偶联质量控制机制，可以解决共价 RNA-蛋白质交联问题。翻译核糖体和交联 mRNA 结合蛋白之间的碰撞触发它们被非典型 K6 和 K48 连接的泛素链修饰。泛素化需要 E3 连接酶 RNF14 并导致蛋白质加合物的蛋白酶体降解。我们的研究结果确定 RNA 损伤引起的翻译应力是交联损伤的核心组成部分。版权所有 © 2023 作者。由爱思唯尔公司出版。保留所有权利。

Reactive aldehydes are abundant endogenous metabolites that challenge homeostasis by crosslinking cellular macromolecules. Aldehyde-induced DNA damage requires repair to prevent cancer and premature aging, but it is unknown whether cells also possess mechanisms that resolve aldehyde-induced RNA lesions. Here, we establish photoactivatable ribonucleoside-enhanced crosslinking (PAR-CL) as a model system to study RNA crosslinking damage in the absence of confounding DNA damage in human cells. We find that such RNA damage causes translation stress by stalling elongating ribosomes, which leads to collisions with trailing ribosomes and activation of multiple stress response pathways. Moreover, we discovered a translation-coupled quality control mechanism that resolves covalent RNA-protein crosslinks. Collisions between translating ribosomes and crosslinked mRNA-binding proteins trigger their modification with atypical K6- and K48-linked ubiquitin chains. Ubiquitylation requires the E3 ligase RNF14 and leads to proteasomal degradation of the protein adduct. Our findings identify RNA lesion-induced translational stress as a central component of crosslinking damage.Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.