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通过TRiC介导的TCAB1折叠,对端粒酶功能的蛋白质静止控制
Adam Freund1, Franklin L Zhong2, Andrew S Venteicher1
1Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA.
Cell
|December 4, 2014
概括
沙佩罗宁TRiC通过折叠其辅因子TCAB1.1,对端粒酶功能至关重要. 损坏的TRiC功能会扰乱端粒的维护,导致衰老和先天性皮质障碍.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 端粒维护对细胞功能至关重要,并且在衰老和干细胞疾病中受损,如先天性硬.
- 端粒酶是负责端粒维护的酶,其组装,定位和功能依赖于复杂的途径.
研究的目的:
- 为了确定端粒酶贩运和卡哈尔体局部化的新型调节者.
- 阐明蛋白质折叠在端粒酶通路功能中的作用及其与人类疾病的联系.
主要方法:
- 在人类细胞中使用了高含量的全基因组siRNA屏幕,以确定Cajal体中端粒酶局部化所必需的因素.
- 进行了功能性测试,以评估确定因素对TCAB1蛋白折叠,端粒酶贩运和端粒延长的影响.
主要成果:
- 查佩罗宁CCT/TRiC被确定为端粒酶贩运的关键调节剂.
- TRiC对于端粒酶辅因子TCAB1的适当折叠至关重要,该辅因子控制着端粒酶和小Cajal体RNAs (scaRNAs) 的贩运.
- TRiC的耗尽导致TCAB1的损失,端粒酶和scaRNAs到核细胞的错位,以及端粒延长受损.
结论:
- 由TRiC介导的蛋白质折叠是端粒酶通路中的关键步骤,对于端粒维护至关重要.
- 患有Dyskeratosis congenita TCAB1的患者衍生突变会损害TRiC介导的折叠,连接蛋白质稳定,端粒生物学和疾病发病.
- 这项研究确立了蛋白质折叠机制,端粒维护和人类干细胞疾病之间的直接联系.
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