神经细胞黏附分子NCAM2的Ig1结构域的晶体结构显示出结构域交换。

Crystal structure of the Ig1 domain of the neural cell adhesion molecule NCAM2 displays domain swapping.

作者信息

Rasmussen Kim K, Kulahin Nikolaj, Kristensen Ole, Poulsen Jens-Christian N, Sigurskjold Bent W, Kastrup Jette S, Berezin Vladimir, Bock Elisabeth, Walmod Peter S, Gajhede Michael

机构信息

Protein Laboratory, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark.

出版信息

J Mol Biol. 2008 Oct 24;382(5):1113-20. doi: 10.1016/j.jmb.2008.07.084. Epub 2008 Aug 6.

DOI:10.1016/j.jmb.2008.07.084

PMID:18706912

Abstract

The crystal structure of the first immunoglobulin (Ig1) domain of neural cell adhesion molecule 2 (NCAM2/OCAM/RNCAM) is presented at a resolution of 2.7 A. NCAM2 is a member of the immunoglobulin superfamily of cell adhesion molecules (IgCAMs). In the structure, two Ig domains interact by domain swapping, as the two N-terminal beta-strands are interchanged. beta-Strand swapping at the terminal domain is the accepted mechanism of homophilic interactions amongst the cadherins, another class of CAMs, but it has not been observed within the IgCAM superfamily. Gel-filtration chromatography demonstrated the ability of NCAM2 Ig1 to form dimers in solution. Taken together, these observations suggest that beta-strand swapping could have a role in the molecular mechanism of homophilic binding for NCAM2.

摘要

神经细胞粘附分子2（NCAM2/OCAM/RNCAM）首个免疫球蛋白（Ig1）结构域的晶体结构以2.7埃的分辨率呈现。NCAM2是细胞粘附分子免疫球蛋白超家族（IgCAMs）的成员。在该结构中，两个Ig结构域通过结构域交换相互作用，因为两个N端β链发生了互换。末端结构域的β链交换是另一类细胞粘附分子钙粘蛋白之间同源相互作用的公认机制，但在IgCAM超家族中尚未观察到。凝胶过滤色谱法证明NCAM2 Ig1在溶液中能够形成二聚体。综上所述，这些观察结果表明β链交换可能在NCAM2的同源结合分子机制中发挥作用。