Department of Biology, University of Konstanz, 78457 Konstanz, Germany.
Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong.
Plant Cell. 2024 Sep 3;36(9):3074-3098. doi: 10.1093/plcell/koae141.
Proteome composition is dynamic and influenced by many internal and external cues, including developmental signals, light availability, or environmental stresses. Protein degradation, in synergy with protein biosynthesis, allows cells to respond to various stimuli and adapt by reshaping the proteome. Protein degradation mediates the final and irreversible disassembly of proteins, which is important for protein quality control and to eliminate misfolded or damaged proteins, as well as entire organelles. Consequently, it contributes to cell resilience by buffering against protein or organellar damage caused by stresses. Moreover, protein degradation plays important roles in cell signaling, as well as transcriptional and translational events. The intricate task of recognizing specific proteins for degradation is achieved by specialized systems that are tailored to the substrate's physicochemical properties and subcellular localization. These systems recognize diverse substrate cues collectively referred to as "degrons," which can assume a range of configurations. They are molecular surfaces recognized by E3 ligases of the ubiquitin-proteasome system but can also be considered as general features recognized by other degradation systems, including autophagy or even organellar proteases. Here we provide an overview of the newest developments in the field, delving into the intricate processes of protein recognition and elucidating the pathways through which they are recruited for degradation.
蛋白质组组成是动态的，受许多内部和外部线索的影响，包括发育信号、光照可用性或环境压力。蛋白质降解与蛋白质生物合成协同作用，使细胞能够通过重塑蛋白质组来响应各种刺激并进行适应。蛋白质降解介导蛋白质的最终和不可逆的解体，这对于蛋白质质量控制以及消除错误折叠或受损的蛋白质以及整个细胞器非常重要。因此，它通过缓冲应激引起的蛋白质或细胞器损伤来促进细胞的弹性。此外，蛋白质降解在细胞信号转导以及转录和翻译事件中发挥重要作用。专门的系统通过识别特定的降解底物的理化性质和亚细胞定位来完成识别特定蛋白质进行降解的复杂任务。这些系统识别多种底物线索，统称为“降解标签”，它们可以呈现出多种形式。它们是泛素-蛋白酶体系统的 E3 连接酶识别的分子表面，但也可以被视为其他降解系统（包括自噬甚至细胞器蛋白酶）识别的一般特征。在这里，我们提供了该领域最新进展的概述，深入探讨了蛋白质识别的复杂过程，并阐明了它们被招募进行降解的途径。
