The ubiquitin/26S proteasome pathway largely mediates selective proteolysis in the nucleus and cytosol. This pathway catalyzes covalent attachment of ubiquitin (UBQ) to substrate proteins in an E1-E2-E3 cascade. Ubiquitin E3 ligases interact with substrates to catalyze UBQ transfer from E2 to substrate. Within the E3 ligase superfamily, cullin RING ligases (CRLs) are significant in plants because they are linked to hormonal signaling, developmental programs, and environmental responses. Thus, knowledge of CRL regulation is required for a complete understanding of these processes. A major mechanism modulating CRL activity is modification of the cullin subunit by RUB (RELATED TO UBIQUITIN), a ubiquitin-like protein, and demodification by the COP9 signalosome (CSN). CULLIN-ASSOCIATED NEDD8-DISSOCIATED 1 (CAND1) interacts with CRLs, affecting both rubylation and derubylation. Described here are the pathways, regulation, and biological function of rubylation and derubylation, as well as future directions and outstanding questions.

中文翻译：

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Cullin RING 连接酶的调控

泛素/26S 蛋白酶体途径主要介导细胞核和细胞质中的选择性蛋白水解。该途径在 E1-E2-E3 级联反应中催化泛素 (UBQ) 与底物蛋白的共价连接。泛素 E3 连接酶与底物相互作用以催化 UBQ 从 E2 转移到底物。在 E3 连接酶超家族中，cullin RING 连接酶 (CRL) 在植物中很重要，因为它们与激素信号、发育程序和环境反应有关。因此，要全面了解这些过程，需要了解 CRL 法规。调节 CRL 活性的主要机制是通过 RUB（与泛素相关的蛋白）修饰 cullin 亚基，这是一种泛素样蛋白，并通过 COP9 信号小体 (CSN) 进行解修饰。CULLIN 相关 NEDD8-分离 1 (CAND1) 与 CRL 相互作用，影响红宝石化和去红宝石化。这里描述了红宝石化和去红宝石化的途径、调控和生物学功能，以及未来的方向和悬而未决的问题。