Wolf Dieter A, Zhou Chunshui, Wee Susan
Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, MA 02115, USA.
Nat Cell Biol. 2003 Dec;5(12):1029-33. doi: 10.1038/ncb1203-1029.
The COP9 signalosome (CSN) is a highly conserved protein complex implicated in diverse biological functions that involve ubiquitin-mediated proteolysis. Paradoxically, conserved enzymatic activities associated with CSN inhibit cullin ubiquitin ligase activity in vitro, whereas mutational analysis suggests that CSN promotes cullin-dependent proteolysis in vivo. This apparent paradox can be resolved in a model that proposes CSN-mediated cullin inhibition is a prerequisite for the proper assembly and maintenance of active cullin ubiquitin ligase complexes.
COP9信号体（CSN）是一种高度保守的蛋白质复合物，参与多种涉及泛素介导的蛋白水解的生物学功能。矛盾的是，与CSN相关的保守酶活性在体外抑制cullin泛素连接酶活性，而突变分析表明CSN在体内促进依赖cullin的蛋白水解。在一个模型中可以解决这一明显的矛盾，该模型提出CSN介导的cullin抑制是活性cullin泛素连接酶复合物正确组装和维持的先决条件。
