Seufert W, Jentsch S
Friedrich-Miescher-Laboratorium der Max-Planck-Gesellschaft, Tübingen, Germany.
EMBO J. 1992 Aug;11(8):3077-80. doi: 10.1002/j.1460-2075.1992.tb05379.x.
A major eukaryotic proteolytic system is known to require the covalent attachment of ubiquitin to substrates prior to their degradation, yet the proteinase involved remains poorly defined. The proteasome, a large conserved multi-subunit protein complex of the cytosol and the nucleus, has been implicated in a variety of cellular functions. It is shown here that a yeast mutant with a defective proteasome fails to degrade proteins which are subject to ubiquitin-dependent proteolysis in wild-type cells. Thus, the proteasome is part of the ubiquitin system and mediates the degradation of ubiquitin-protein conjugates in vivo.
已知一种主要的真核生物蛋白水解系统在底物降解之前需要将泛素共价连接到底物上，然而所涉及的蛋白酶仍未明确界定。蛋白酶体是细胞质和细胞核中一种大型保守的多亚基蛋白质复合物，已被认为参与多种细胞功能。本文表明，蛋白酶体有缺陷的酵母突变体无法降解在野生型细胞中会被泛素依赖性蛋白水解的蛋白质。因此，蛋白酶体是泛素系统的一部分，并在体内介导泛素 - 蛋白质缀合物的降解。
