Strous G J, Govers R
Department of Cell Biology, Faculty of Medicine and Institute of Biomembranes, Utrecht University AZU G02.525, The Netherlands.
J Cell Sci. 1999 May;112 ( Pt 10):1417-23. doi: 10.1242/jcs.112.10.1417.
Internalization of membrane proteins has been studied for more than three decades without solving all the underlying mechanisms. Our knowledge of clathrin-mediated endocytosis is certainly sufficient to understand the basic principles. However, more detailed insight is required to recognize why different proteins enter clathrin-coated pits with different rates and affinities. In addition to clathrin coat components, at least two adaptor systems and even more accessory proteins have been described to preselect membrane proteins before they can enter cells. Recent experimental data have identified the ubiquitin-proteasome system as a regulatory system for endocytosis. This system is well-known for its basic regulatory function in protein degradation, and controls a magnitude of key events. The ubiquitin-proteasome system is now identified as a regulator of the endocytosis of selected membrane proteins. In this review, we will discuss the complexity and implications of this mechanism for receptor-mediated endocytosis.
膜蛋白的内化已经研究了三十多年，但尚未解决所有潜在机制。我们对网格蛋白介导的内吞作用的了解肯定足以理解其基本原理。然而，需要更详细的见解来认识为什么不同的蛋白质以不同的速率和亲和力进入网格蛋白包被小窝。除了网格蛋白包被成分外，还描述了至少两种衔接蛋白系统以及更多辅助蛋白，以便在膜蛋白进入细胞之前对其进行预选。最近的实验数据已将泛素-蛋白酶体系统确定为内吞作用的调节系统。该系统因其在蛋白质降解中的基本调节功能而闻名，并控制着一系列关键事件。泛素-蛋白酶体系统现在被确定为所选膜蛋白内吞作用的调节因子。在这篇综述中，我们将讨论这种机制对受体介导的内吞作用的复杂性和影响。
