Rosenthal J A, Chen H, Slepnev V I, Pellegrini L, Salcini A E, Di Fiore P P, De Camilli P
Howard Hughes Medical Institute and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
J Biol Chem. 1999 Nov 26;274(48):33959-65. doi: 10.1074/jbc.274.48.33959.
Epsin (epsin 1) is an interacting partner for the EH domain-containing region of Eps15 and has been implicated in conjunction with Eps15 in clathrin-mediated endocytosis. We report here the characterization of a similar protein (epsin 2), which we have cloned from human and rat brain libraries. Epsin 1 and 2 are most similar in their NH(2)-terminal region, which represents a module (epsin NH(2) terminal homology domain, ENTH domain) found in a variety of other proteins of the data base. The multiple DPW motifs, typical of the central region of epsin 1, are only partially conserved in epsin 2. Both proteins, however, interact through this central region with the clathrin adaptor AP-2. In addition, we show here that both epsin 1 and 2 interact with clathrin. The three NPF motifs of the COOH-terminal region of epsin 1 are conserved in the corresponding region of epsin 2, consistent with the binding of both proteins to Eps15. Epsin 2, like epsin 1, is enriched in brain, is present in a brain-derived clathrin-coated vesicle fraction, is concentrated in the peri-Golgi region and at the cell periphery of transfected cells, and partially colocalizes with clathrin. High overexpression of green fluorescent protein-epsin 2 mislocalizes components of the clathrin coat and inhibits clathrin-mediated endocytosis. The epsins define a new protein family implicated in membrane dynamics at the cell surface.
Epsin（epsin 1）是Eps15含EH结构域区域的相互作用伙伴，并已被证明与Eps15共同参与网格蛋白介导的内吞作用。我们在此报告一种类似蛋白质（epsin 2）的特性，它是我们从人和大鼠脑文库中克隆出来的。Epsin 1和2在其NH₂末端区域最为相似，该区域代表了在数据库中多种其他蛋白质中发现的一个模块（epsin NH₂末端同源结构域，ENTH结构域）。epsin 1中央区域典型的多个DPW基序在epsin 2中仅部分保守。然而，这两种蛋白质都通过该中央区域与网格蛋白衔接蛋白AP - 2相互作用。此外，我们在此表明epsin 1和2都与网格蛋白相互作用。epsin 1羧基末端区域的三个NPF基序在epsin 2的相应区域保守，这与两种蛋白质都与Eps15结合一致。Epsin 2与epsin 1一样，在脑中富集，存在于脑源性网格蛋白包被囊泡组分中，集中在高尔基体周围区域和转染细胞的细胞周边，并与网格蛋白部分共定位。绿色荧光蛋白 - epsin 2的高过表达会使网格蛋白包被的组分定位错误，并抑制网格蛋白介导的内吞作用。Epsin蛋白定义了一个与细胞表面膜动态相关的新蛋白质家族。
