Pokidysheva Elena, Zhang Ying, Battisti Anthony J, Bator-Kelly Carol M, Chipman Paul R, Xiao Chuan, Gregorio G Glenn, Hendrickson Wayne A, Kuhn Richard J, Rossmann Michael G
Department of Biological Sciences, Lilly Hall, 915 W. State Street, Purdue University, West Lafayette, IN 47907, USA.
Cell. 2006 Feb 10;124(3):485-93. doi: 10.1016/j.cell.2005.11.042.
Dengue virus (DENV) is a significant human pathogen that causes millions of infections and results in about 24,000 deaths each year. Dendritic cell-specific ICAM3 grabbing nonintegrin (DC-SIGN), abundant in immature dendritic cells, was previously reported as being an ancillary receptor interacting with the surface of DENV. The structure of DENV in complex with the carbohydrate recognition domain (CRD) of DC-SIGN was determined by cryo-electron microscopy at 25 A resolution. One CRD monomer was found to bind to two glycosylation sites at Asn67 of two neighboring glycoproteins in each icosahedral asymmetric unit, leaving the third Asn67 residue vacant. The vacancy at the third Asn67 site is a result of the nonequivalence of the glycoprotein environments, leaving space for the primary receptor binding to domain III of E. The use of carbohydrate moieties for receptor binding sites suggests a mechanism for avoiding immune surveillance.
登革病毒（DENV）是一种重要的人类病原体，每年导致数百万感染病例，并造成约24000人死亡。树突状细胞特异性细胞间黏附分子3抓取非整合素（DC-SIGN）在未成熟树突状细胞中大量存在，此前有报道称其为与登革病毒表面相互作用的辅助受体。通过冷冻电子显微镜以25埃分辨率确定了与DC-SIGN的碳水化合物识别结构域（CRD）结合的登革病毒结构。发现一个CRD单体在每个二十面体不对称单元中与两个相邻糖蛋白的Asn67处的两个糖基化位点结合，使第三个Asn67残基空缺。第三个Asn67位点的空缺是糖蛋白环境不等价的结果，为主要受体与E结构域III结合留出了空间。利用碳水化合物部分作为受体结合位点提示了一种逃避免疫监视的机制。
