Park Sang Yoon, Guo Xiaoli
*Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, 20892, U.S.A.
Biosci Rep. 2014 Jul 29;34(4):e00123. doi: 10.1042/BSR20140069.
The AP (adaptor protein) complexes are heterotetrameric protein complexes that mediate intracellular membrane trafficking along endocytic and secretory transport pathways. There are five different AP complexes: AP-1, AP-2 and AP-3 are clathrin-associated complexes; whereas AP-4 and AP-5 are not. These five AP complexes localize to different intracellular compartments and mediate membrane trafficking in distinct pathways. They recognize and concentrate cargo proteins into vesicular carriers that mediate transport from a donor membrane to a target organellar membrane. AP complexes play important roles in maintaining the normal physiological function of eukaryotic cells. Dysfunction of AP complexes has been implicated in a variety of inherited disorders, including: MEDNIK (mental retardation, enteropathy, deafness, peripheral neuropathy, ichthyosis and keratodermia) syndrome, Fried syndrome, HPS (Hermansky-Pudlak syndrome) and HSP (hereditary spastic paraplegia).
衔接蛋白（AP）复合物是异源四聚体蛋白复合物，介导沿内吞和分泌运输途径的细胞内膜运输。有五种不同的AP复合物：AP-1、AP-2和AP-3是网格蛋白相关复合物；而AP-4和AP-5则不是。这五种AP复合物定位于不同的细胞内区室，并介导不同途径中的膜运输。它们识别货物蛋白并将其浓缩到囊泡载体中，介导从供体膜到靶细胞器膜的运输。AP复合物在维持真核细胞的正常生理功能中发挥重要作用。AP复合物功能障碍与多种遗传性疾病有关，包括：梅德尼克（智力发育迟缓、肠病、耳聋、周围神经病变、鱼鳞病和皮肤角化病）综合征、弗里德综合征、赫尔曼斯基-普德拉克综合征（HPS）和遗传性痉挛性截瘫（HSP）。
