Department of Molecular Biology and Genetics, 107 Biotechnology Bldg., Cornell University, Ithaca, NY 14853-7202, USA.
Trends Cell Biol. 2011 Sep;21(9):515-25. doi: 10.1016/j.tcb.2011.05.005. Epub 2011 Jul 19.
Cell polarity in eukaryotes requires constant sorting, packaging and transport of membrane-bound cargo within the cell. These processes occur in two sorting hubs: the recycling endosome for incoming material and the trans-Golgi network for outgoing material. Phosphatidylinositol 3-phosphate and phosphatidylinositol 4-phosphate are enriched at the endocytic and exocytic sorting hubs, respectively, where they act together with small GTPases to recruit factors to segregate cargo and regulate carrier formation and transport. In this review, we summarize the current understanding of how these lipids and GTPases regulate membrane trafficking directly, emphasizing the recent discoveries of phosphatidylinositol 4-phosphate functions at the trans-Golgi network.
真核生物的细胞极性需要不断地对细胞内的膜结合货物进行分类、包装和运输。这些过程发生在两个分拣中心：回收内体用于接收物质，以及高尔基网络用于输出物质。磷脂酰肌醇 3-磷酸和磷脂酰肌醇 4-磷酸分别在内吞和外排分拣中心富集，在那里它们与小 GTP 酶一起作用，招募因子来分隔货物并调节载体的形成和运输。在这篇综述中，我们总结了目前对这些脂质和 GTP 酶如何直接调节膜运输的理解，强调了最近在高尔基网络中发现的磷脂酰肌醇 4-磷酸的功能。
