摘 要：摘 要：蛋白质翻译后修饰对改变蛋白功能、活性或定位都起着非常重要的作用，泛素及其相似蛋白的修饰是其中一种重要形式。与其他诸如磷酸化、乙酰化、糖基化等不同的是，泛素及其相似蛋白的修饰基团本身即是一个小的多肽，通过异肽键与靶蛋白Lys侧链e-NH2相连，其中小泛素相关修饰物（small ubiquitin-related modifier，SUMO）与蛋白的共价连接是一种新的广泛存在的翻译后修饰形式。SUMO是广泛存在于真核生物中高度保守的蛋白家族，在脊椎动物中有三个SUMO基因，称为SUMO-1,-2,-3，与泛素在二级结构上极其相似，且催化修饰过程的酶体系也具有很高的同源性。然而，与泛素化介导的蛋白酶降解途径不同，SUMO化修饰发挥着更为广泛的功能，如核质转运、细胞周期调控、信号转导、转录活性调控等。
关键词：翻译后修饰；UBLs；SUMO化；去SUMO化
Abstract: Abstract: Post-translational modification of proteins is an important means to alter their function, activity or localization after their synthesis has been completed, including phosphorylation, acetylation and glycation. Modification with ubiquitin and ubiquitin-like modifiers represent a unique case because the modifier itself is a small polypeptide, and is usually attached to lysine side chains of target protein, resulting in isopeptide linked conjugates. SUMO is a highly conserved, small ubiquitin-related modifier that has been shown to be covalently conjugated to a variety of cellular proteins. There are three members of the SUMO family described in vertebrates: SUMO-1,-2,-3. It has remarkably similar secondary structure with ubiquitin and is covalently conjugated to other proteins in a similar multistep process to ubiquitination. However, unlike the ubiquitin system, which primarily targets substrate proteins to the proteasome for degradation, sumolyzation participates in a number of cellular processes such as nuclear transport, transcriptional regulation, apoptosis and cell cycle control.
Key words: post-translational modification; ubiquitin-like modifiers(UBLs); SUMO conjugation; SUMO de-conjugation
