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乌比奎丁E3结合酶BFAR促进PNPLA3的降解
Avash Das1, Haili Cheng1, Yang Wang1
1Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390.
概括
双功能性亡调节器 (BFAR) 针对含有帕塔丁类脂酶域蛋白3 (PNPLA3) 的降解,影响脂肪肝疾病的风险. 识别BFAR为管理PNPLA3水平和预防脂肪肝疾病提供了一个新的治疗标.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 帕塔丁类脂酶域含有蛋白3 (PNPLA3) I148M变体是脂肪肝疾病 (FLD) 的关键遗传风险因素.
- PNPLA3通过蛋白酶体和自酶体经历无处不在和降解,这一过程被I148M变种破坏.
研究的目的:
- 为了确定负责PNPLA3营业额的特定E3泛基因酶.
- 阐明双功能性亡调节器 (BFAR) 在PNPLA3翻译后修饰和降解中的作用.
主要方法:
- 小干扰性 (si) RNAs被用来使培养肝细胞中的无素蛋白酶体系统组件失活.
- 进行了共免疫沉试验和体外无处不在试验.
- 双功能性亡调节器 (BFAR) 基因在小鼠中被禁用,以在体内评估PNPLA3蛋白水平.
主要成果:
- 无活化BFAR增加了肝细胞中的PNPLA3蛋白水平,而BFAR过度表达则降低了它们.
- 在实验室中,BFAR和PNPLA3被证明是共免疫沉,BFAR直接无处不在的PNPLA3.
- 缺乏BFAR的小鼠显示肝脏PNPLA3蛋白水平增加了两倍,mRNA水平没有变化.
结论:
- 双功能性亡调节器 (BFAR) 作为一个E3泛基因结合酶,准PNPLA3进行翻译后降解.
- BFAR是PNPLA3周转机制的一个关键组成部分.
- 向BFAR是一种潜在的治疗策略,可以增强PNPLA3降解并减轻脂肪肝疾病的进展.
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