Chan Ling-Shan, Moshkanbaryans Lia, Xue Jing, Graham Mark E
Children's Medical Research Institute, The University of Sydney, Westmead, New South Wales, Australia.
PLoS One. 2014 Oct 20;9(10):e110557. doi: 10.1371/journal.pone.0110557. eCollection 2014.
Brain-specific AP180 is present in clathrin coats at equal concentration to the adapter complex, AP2, and assembles clathrin faster than any other protein in vitro. Both AP180 and its ubiquitously expressed homolog clathrin assembly lymphoid myeloid leukemia protein (CALM) control vesicle size and shape in clathrin mediated endocytosis. The clathrin assembly role of AP180 is mediated by a long disordered C-terminal assembly domain. Within this assembly domain, a central acidic clathrin and adapter binding (CLAP) sub-domain contains all of the known short binding motifs for clathrin and AP2. The role of the remaining ∼ 16 kDa C-terminal sequence has not been clear. We show that this sequence has a separate function in ensuring efficient binding of clathrin, based on in vitro binding and ex vivo transferrin uptake assays. Sequence alignment suggests the C-terminal sub-domain is conserved in CALM.
脑特异性AP180在网格蛋白包被中与衔接蛋白复合物AP2浓度相当，并且在体外比其他任何蛋白质都能更快地组装网格蛋白。AP180及其普遍表达的同源物网格蛋白组装淋巴样髓性白血病蛋白（CALM）在网格蛋白介导的内吞作用中均控制囊泡的大小和形状。AP180的网格蛋白组装作用由一个长的无序C末端组装结构域介导。在这个组装结构域内，一个中央酸性网格蛋白和衔接蛋白结合（CLAP）亚结构域包含所有已知的与网格蛋白和AP2结合的短基序。其余约16 kDa的C末端序列的作用尚不清楚。基于体外结合和体内转铁蛋白摄取试验，我们表明该序列在确保网格蛋白的有效结合方面具有独立功能。序列比对表明C末端亚结构域在CALM中是保守的。
