泛素是一个由76个氨基酸组成的高度保守的多肽链,因其广泛分布于各类细胞而得名。泛素共价地结合于 底物蛋白质的赖氨酸残基,被泛素标记的蛋白质将被特异性地识别并迅速降解,泛素的这种标记作用是非底物特异性的,在蛋白质降解过程中泛素的枢纽作用越来越 得到研究者的重视。细胞中的蛋白质处于不断地降解与更新的过程中,保持细胞正常的蛋白质代谢对于生命的正常功能至关重要。控制蛋白质降解的机制尚未阐明, 现在已清楚细胞蛋白的降解是一个复杂的、被严密调控的过程,此过程在细胞疾病和健康状态、生存和死亡的一系列基本过程中(细胞凋亡、DNA修复等)扮演重 要角色, 蛋白质降解异常与许多疾病(恶性肿瘤,神经退行性疾患等)的发生密切相关。基因的功能是通过蛋白质的表达实现的,而泛素在蛋白质降解中的作用机制如能被阐 明将对解释多种疾病的发生机制和遗传信息的调控表达有重要意义。2004年,Aaron Ciechanover、Avram Hershko、Irwin Rose因发现了泛素调解的蛋白质降解过程而获得了诺贝尔化学奖。
泛素化蛋白修饰之共价结合反应(conjugation)系由三组酵素,即激活酵素(E1)、接合酵素(E2)及泛素/类泛素连接酶 (ubiquitin/UBL-protein ligase)(E3)进行一连串的分子活化作用构成,此作用的特异性则取决于种类众多之E3连接酶与受质间专一性辨识之能力,而泛素或类泛素本身在此种 蛋白修饰作用中则是主要提供受质与其它蛋白交互作用之结构介面,藉以影响蛋白受质之细胞内命运。
相关产品信息:
泛素体及类似体(Ubiquiton and Derivatives)
泛素体激活酶,交联酶与连接酶(E1s, E2s, & E3s)
泛素体裂解酶(Ubiquiton Deconjugating Enzymes)
泛素体相关底物与抑制剂 (Ubiquiton-related Substrates and Inhibitors)
泛素结合体(Ubiquitin Binding Entities)
泛素化试剂盒与相关分析系统 (Ubiquitonylation Kits and Systems)
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