Adaptor protein Ruk/CIN85 is associated with a subset of COPI-Coated membranes of the Golgi complex
Adaptor protein Ruk/CIN85 is associated with a subset of COPI-Coated membranes of the Golgi complex
复制标题
DOI：
10.1111/j.1600-0854.2008.00724.x
复制
发表时间：
2008-05-01
期刊：
影响因子：
4.5
通讯作者：
Buchman, Vladimir L.
中科院分区：
文献类型：
--
作者：
Havrylov, Serhiy;Ichioka, Fumitaka;Buchman, Vladimir L.
85 kDa 的普遍激酶/Cbl 相互作用蛋白 (Ruk/CIN85) 和具有多个 SH3 结构域的 CD2 相关蛋白/Cas 配体 (CD2AP/CMS) 的调节剂包含参与几个重要细胞过程的脊椎动物接头蛋白家族，包括激活受体酪氨酸激酶的下调、细胞骨架重排的调节、磷脂酰肌醇 3-激酶 (PI 3-激酶) 信号传导和细胞凋亡。 Ruk/CIN85 作为参与膜运输过程的支架蛋白的作用已在模型细胞系统中得到证实。然而，内源性 Ruk/CIN85 的细胞内定位从未得到全面评估。我们使用识别蛋白质不同表位的抗体对 Ruk/CIN85 在贴壁培养的人类细胞中的亚细胞分布进行了详细研究，并揭示了参与细胞内运输过程的蛋白质常见的点状免疫染色模式。我们的数据表明，Ruk/CIN85 分布在几个不同的膜运输区室之间，但 Ruk/CIN85 的主要池与高尔基复合体相关，主要与参与逆行内质网-高尔基体和高尔基体内运输的 COPI 包被囊泡亚群相关。这种定位模式取决于高尔基复合体和完整微管网络的完整性。只有一小部分 Ruk/CIN85 存在于参与网格蛋白介导的内吞作用和分选的区室中。这些结果表明内源性 Ruk/CIN85 可能参与特定膜运输过程的调节。
Regulator of ubiquitous kinase/Cbl-interacting protein of 85 kDa (Ruk/CIN85) and CD2-associated protein/Cas ligand with multiple SH3 domains (CD2AP/CMS) comprise a family of vertebrate adaptor proteins involved in several important cellular processes, including downregulation of activated receptor tyrosine kinases, regulation of cytoskeletal rearrangements, phosphatidylinositol 3-kinase (PI 3-kinase) signalling and apoptosis. The role of Ruk/CIN85 as a scaffold protein involved in membrane trafficking processes has been demonstrated in model cell systems. However, intracellular localization of endogenous Ruk/CIN85 has never been comprehensively assessed. We carried out detailed studies of subcellular distribution of Ruk/CIN85 in adherent cultured human cells using antibodies that recognize distinct epitopes of the protein and revealed a punctate immunostaining pattern, common for proteins involved in intracellular trafficking processes. Our data indicate that Ruk/CIN85 is distributed between several different membrane trafficking compartments, but the major pool of Ruk/CIN85 is associated with the Golgi complex, mainly with a subpopulation of COPI-coated vesicles involved in retrograde endoplasmic reticulum-Golgi and intra-Golgi transport. This localization pattern is dependent on the integrity of Golgi complex and intact microtubular network. Only a small pool of Ruk/CIN85 is present in compartments involved in clathrin-mediated endocytosis and sorting. These results suggest that endogenous Ruk/CIN85 may be involved in regulation of specific membrane trafficking processes.