e6-ap与蛋白降解

E6-AP and Protein Degradation

e6-ap基因是HECTE3蛋白家族成员，根据N端的不同分为3个转录本，编码的3种蛋白均具有降解蛋白的功能。E6-AP的功能复杂，主要包括：①降解抑癌基因如p53、pml、tsc2、pdz家族基因的功能；②诱导htert基因启动子激活、提高端粒酶活性的功能；③与C型肝炎病毒的核心蛋白结合，参与r6基因的降解；④双向调节固醇类激素受体的表达；⑤调节ANNEXINA1蛋白的表达、促进其降解。E6-AP的蛋白表达受泛素及E6的调控，在肿瘤发病机制中起着重要作用。

E6-AP, one of HECT E3 protein family members, is divided into three different transcripts on the basis of its N-terminus that encodes three proteins with the ability of protein degradation. The function of E6-AP is complicated, including ： ① degrading tumor suppressor genes such as p53, PML, TSC2, PDZ family of genes ;② inducing activation of hTERT promoter and enhancing telomerase activity;③ binding to hepatitis C virus core protein, and participating in degradation of Rb gene; ④ dually regulating expression of steroid hormone receptor; ⑤ regulating expression of annexin A1 protein and promoting its degradation. E6-AP is regulated by ubiquitin and E6, and plays an important role in tumorigenesis.