A balance between the synthesis and degradation of active proteins governs diverse cellular processes in plants, spanning from cell‐cycle progression and circadian rhythm to the outcome of several hormone signalling pathways. Ubiquitin‐mediated post‐translational modification determines the degradative fate of the target proteins, thereby altering the output of cellular processes. An equally important, and perhaps under‐appreciated, aspect of this pathway is the antagonistic process of de‐ubiquitination. De‐ubiquitinases (DUBs), a group of processing enzymes, play an important role in maintaining cellular ubiquitin homeostasis by hydrolyzing ubiquitin poly‐proteins and free poly‐ubiquitin chains into mono‐ubiquitin. Further, DUBs rescue the cellular proteins from 26S proteasome‐mediated degradation to their active form by cleaving the poly‐ubiquitin chain from the target protein. Any perturbation in DUB activity is likely to affect proteostasis and downstream cellular processes. This review illustrates recent findings on the biological significance and mechanisms of action of the DUBs in Arabidopsis thaliana , with an emphasis on ubiquitin‐specific proteases (UBPs), the largest family among the DUBs. We focus on the putative roles of various protein–protein interaction interfaces in DUBs and their generalized function in ubiquitin recycling, along with their pre‐eminent role in plant development.

中文翻译：

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移动中的泛素化酶：植物生物学的新兴领域。

活性蛋白的合成与降解之间的平衡控制着植物的各种细胞过程，从细胞周期进程和昼夜节律到几种激素信号通路的结果。泛素介导的翻译后修饰决定了目标蛋白的降解命运，从而改变了细胞过程的输出。该途径的一个同样重要的，也许是未被重视的方面是去泛素化的拮抗过程。去泛素化酶（DUBs）是一组加工酶，通过将泛素多聚蛋白和游离的泛素链水解成单泛素，在维持细胞泛素稳态中起着重要作用。进一步，DUB通过将多泛素链从靶蛋白上裂解下来，将细胞蛋白从26S蛋白酶体介导的降解中解救为活性形式。DUB活动的任何干扰都可能影响蛋白稳态和下游细胞过程。这项审查阐明了最近的发现关于DUBs的生物学意义和作用机制。拟南芥，着重于泛素特异性蛋白酶（UBP），这是DUB中最大的家族。我们关注DUB中各种蛋白质间相互作用界面的推定作用及其在泛素回收中的广义功能，以及它们在植物发育中的杰出作用。