Koshiba Seizo, Kigawa Takanori, Kikuchi Akira, Yokoyama Shigeyuki
Genomic Sciences Center, RIKEN Yokohama Institute, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.
J Struct Funct Genomics. 2002;2(1):1-8. doi: 10.1023/a:1011397007366.
Epsin is a protein that binds to the Eps15 homology (EH) domains, and is involved in clathrin-mediated endocytosis. The epsin N-terminal homology (ENTH) domain (about 140 amino acid residues) is well conserved in eukaryotes and is considered to be important for actin cytoskeleton organization in endocytosis. In this study, we have determined the solution structure of the ENTH domain (residues 1-144) of human epsin by multidimensional nuclear magnetic resonance spectroscopy. In the ENTH-domain structure, seven alpha-helices form a superhelical fold, consisting of two antiparallel two-helix HEAT motifs and one three-helix ARM motif, with a continuous hydrophobic core in the center. We conclude that the seven-helix superhelical fold defines the ENTH domain, and that the previously-reported eight-helix fold of a longer fragment of rat epsin 1 is divided into the authentic ENTH domain and a C-terminal flanking alpha-helix.
Epsin是一种与Eps15同源（EH）结构域结合的蛋白质，参与网格蛋白介导的内吞作用。Epsin N端同源（ENTH）结构域（约140个氨基酸残基）在真核生物中高度保守，被认为对内吞作用中肌动蛋白细胞骨架的组织很重要。在本研究中，我们通过多维核磁共振光谱法确定了人Epsin的ENTH结构域（第1-144位残基）的溶液结构。在ENTH结构域结构中，七个α螺旋形成一个超螺旋折叠，由两个反平行的双螺旋HEAT基序和一个三螺旋ARM基序组成，中心有一个连续的疏水核心。我们得出结论，七螺旋超螺旋折叠定义了ENTH结构域，并且先前报道的大鼠Epsin 1较长片段的八螺旋折叠被分为真实的ENTH结构域和C端侧翼α螺旋。
