Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.
J Proteomics. 2012 Feb 2;75(4):1375-85. doi: 10.1016/j.jprot.2011.11.013. Epub 2011 Nov 20.
The membrane glycoprotein CD82 (KAI1) has attracted increasing attention as a suppressor of cell migration, related tumor invasion, as well as metastasis. The glycosylation of CD82 has been shown to be involved in a correlative cell adhesion and motility. However, the N-glycosylation pattern of CD82 has not been described yet. In the current study, a detailed characterization of the recombinant human CD82 N-linked glycosylation pattern was conducted by employing an integrative proteomic and glycomic approach, including glycosidase and protease digestions, glycan permethylation, MS analyses, site-directed mutagenesis, and lectin blots. The results reveal three N-glycosylation sites, and further demonstrate a putative glycosylation site at Asn(157) for the first time. A highly heterogeneous pattern of N-linked glycans is described, which express distinct carbohydrate epitopes, such as bisecting N-acetylglucosamine, (α-2,6) N-acetylneuraminic acid, and core fucose. These epitopes are highly associated with various biological functions, including cell adhesion and cancer metastasis, and can possibly influence the anti-cancer inhibition ability of CD82.
膜糖蛋白 CD82（KAI1）作为细胞迁移、相关肿瘤侵袭和转移的抑制剂，受到了越来越多的关注。已经表明 CD82 的糖基化与细胞黏附和运动相关。然而，CD82 的 N-糖基化模式尚未被描述。在本研究中，采用整合的蛋白质组学和糖组学方法，包括糖苷酶和蛋白酶消化、糖基 permethylation、MS 分析、定点突变和凝集素印迹，对重组人 CD82 N-连接糖基化模式进行了详细表征。结果揭示了三个 N-糖基化位点，并首次证明了 Asn(157)上存在一个可能的糖基化位点。描述了一种高度异质的 N-连接聚糖模式，表达了独特的碳水化合物表位，如双分支 N-乙酰葡萄糖胺、（α-2,6）N-乙酰神经氨酸和核心岩藻糖。这些表位与各种生物学功能高度相关，包括细胞黏附和癌症转移，并且可能影响 CD82 的抗癌抑制能力。
