Physiologie Moléculaire de la Cellule, Institut de Biologie et de Médecine Moléculaires (IBMM), Université Libre de Bruxelles (ULB), Gosselies, Belgium.
Trends Cell Biol. 2010 Apr;20(4):196-204. doi: 10.1016/j.tcb.2010.01.004.
Yeast permeases, that act as transporters for nutrients including amino acids, nucleobases and metals, provide a powerful model system for dissecting the physiological control of membrane protein trafficking. Modification of these transporters by ubiquitin is known to target them for degradation in the vacuole, the degradation organelle of fungi. Recent studies have uncovered the role of specific adaptors for recruiting the Rsp5 ubiquitin ligase to these proteins. In addition, the role of ubiquitin at different trafficking steps including early endocytosis, sorting into the multivesicular body (MVB) pathway and Golgi-to-endosome transit is now becoming clear. In particular, K63-linked ubiquitin chains now emerge as a specific signal for protein sorting into the MVB pathway. A complete view of the ubiquitin code governing yeast permease trafficking might not be far off.
酵母渗透酶作为营养物质（包括氨基酸、核苷酸碱基和金属）的转运体，为解析膜蛋白运输的生理控制提供了一个强大的模型系统。众所周知，泛素对这些转运体的修饰可将其靶向到真菌的降解细胞器液泡中进行降解。最近的研究揭示了特定衔接蛋白在将 Rsp5 泛素连接酶募集到这些蛋白质上的作用。此外，泛素在包括早期内吞作用、分拣到多泡体 (MVB) 途径和高尔基体到内体转运在内的不同运输步骤中的作用现在也越来越清楚。特别是，K63 连接的泛素链现在成为蛋白质分拣到 MVB 途径的特定信号。一个完整的泛素密码来控制酵母渗透酶的运输可能即将到来。
