Xu C S, Tung E, Wang I Y, Wang A C
Department of Basic and Clinical Immunology and Microbiology, Medical University of South Carolina, Charleston 29425.
Mol Immunol. 1987 Jul;24(7):791-6. doi: 10.1016/0161-5890(87)90063-0.
Two forms of Thy-1 homologues of apparent mol. wt of 25,000 (designated BTp25) and 45,000 (designated BTp45) were isolated from bovine thymocyte membrane by solubilization, affinity chromatography with Con A, and preparative SDS-PAGE. Both forms reacted with a rabbit antiserum to murine Thy-1 in an enzyme-linked immunosorbent assay (ELISA). BTp45 is most likely a dimer of BTp25, since the two are indistinguishable in their amino acid compositions. Comparison of amino acid compositions of BTp25 and BTp45 to that of rodent and human Thy-1 by the S delta Q index revealed significant relatedness among these molecules. BTp25 and BTp45 demonstrate more structural homology to rodent Thy-1 than to human Thy-1. Detailed chemical analyses indicate that bovine Thy-1 homologues contain neutral sugars and fatty acids covalently bound to the polypeptide chain; therefore, they are lipoglycoproteins.
通过溶解、伴刀豆球蛋白A亲和层析及制备性十二烷基硫酸钠-聚丙烯酰胺凝胶电泳，从牛胸腺细胞膜中分离出两种表观分子量分别为25,000（命名为BTp25）和45,000（命名为BTp45）的Thy-1同源物。在酶联免疫吸附测定（ELISA）中，这两种形式均与兔抗小鼠Thy-1抗血清发生反应。BTp45很可能是BTp25的二聚体，因为二者的氨基酸组成无法区分。通过SδQ指数比较BTp25和BTp45与啮齿动物及人类Thy-1的氨基酸组成，发现这些分子之间存在显著相关性。与人类Thy-1相比，BTp25和BTp45与啮齿动物Thy-1表现出更多的结构同源性。详细的化学分析表明，牛Thy-1同源物含有与多肽链共价结合的中性糖和脂肪酸；因此，它们是脂糖蛋白。
