Kawaguchi Yoshiharu, Kovacs Jeffrey J, McLaurin Adam, Vance Jeffery M, Ito Akihiro, Yao Tso Pang
Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA.
Cell. 2003 Dec 12;115(6):727-38. doi: 10.1016/s0092-8674(03)00939-5.
The efficient clearance of cytotoxic misfolded protein aggregates is critical for cell survival. Misfolded protein aggregates are transported and removed from the cytoplasm by dynein motors via the microtubule network to a novel organelle termed the aggresome where they are processed. However, the means by which dynein motors recognize misfolded protein cargo, and the cellular factors that regulate aggresome formation, remain unknown. We have discovered that HDAC6, a microtubule-associated deacetylase, is a component of the aggresome. We demonstrate that HDAC6 has the capacity to bind both polyubiquitinated misfolded proteins and dynein motors, thereby acting to recruit misfolded protein cargo to dynein motors for transport to aggresomes. Indeed, cells deficient in HDAC6 fail to clear misfolded protein aggregates from the cytoplasm, cannot form aggresomes properly, and are hypersensitive to the accumulation of misfolded proteins. These findings identify HDAC6 as a crucial player in the cellular management of misfolded protein-induced stress.
细胞毒性错误折叠蛋白聚集体的有效清除对细胞存活至关重要。错误折叠的蛋白聚集体通过动力蛋白马达经微管网络从细胞质转运并清除至一种称为聚集体的新型细胞器中进行处理。然而,动力蛋白马达识别错误折叠蛋白货物的方式以及调节聚集体形成的细胞因子仍不清楚。我们发现,一种与微管相关的去乙酰化酶HDAC6是聚集体的一个组成部分。我们证明,HDAC6能够结合多聚泛素化的错误折叠蛋白和动力蛋白马达,从而将错误折叠的蛋白货物招募至动力蛋白马达以转运至聚集体。实际上,缺乏HDAC6的细胞无法从细胞质中清除错误折叠的蛋白聚集体,不能正常形成聚集体,并且对错误折叠蛋白的积累高度敏感。这些发现表明HDAC6是细胞应对错误折叠蛋白诱导应激的关键参与者。