Partial amino acid sequences of the murine fourth component of complement (C4): demonstration of homology with human C4 and identification of the amino-terminal subunit in pro-C4.
Partial amino acid sequences of the murine fourth component of complement (C4): demonstration of homology with human C4 and identification of the amino-terminal subunit in pro-C4.
复制标题
鼠补体第四组分 (C4) 的部分氨基酸序列：证明与人 C4 的同源性并鉴定原 C4 中的氨基末端亚基。
DOI：
10.1073/pnas.77.7.4275
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发表时间：
1980
影响因子：
11.1
通讯作者：
Capra,JD
中科院分区：
文献类型：
--
作者：
Parker,KL;Shreffler,DC;Capra,JD
放射性标记的小鼠C4和C4前体（前C4）从培养的腹腔巨噬细胞纯化免疫沉淀和制备凝胶电泳。分离的亚基的部分NH 2-末端氨基酸序列表明，鼠C4 α、β和γ链均显示出与人C4相应亚基的序列同源性;在鼠C4中鉴定的10个残基中，均与人C4中的残基相同。这些数据扩展到一级结构水平的同源性之间的鼠血清物质（Ss）蛋白和人C4。鼠前C4和分泌的C4的组成多肽链的氨基酸序列的比较表明前C4和C4 β链具有相同的氨基酸序列。这两种分子在位置1处具有赖氨酸，在位置4、5和6处具有亮氨酸，并且在位置7处具有苯丙氨酸。没有序列同源性前C4和α或γ亚基之间被发现。这些结果将β链定义为C4前体分子中的NH 2-末端亚基。
Radiolabeled murine C4 and C4 precursor (pro-C4) from cultured peritoneal macrophages were purified by immunoprecipitation and preparative gel electrophoresis. The partial NH2-terminal amino acid sequences of the isolated subunits demonstrated that murine C4 alpha, beta-, and gamma-chains all show sequence homology with the corresponding subunits of human C4; of the 10 residues identified in murine C4, all are identical to those in human C4. These data extend to the primary structural level the homology between the murine serum substance (Ss) protein and human C4. Comparisons of the amino acid sequences of murine pro-C4 and the constituent polypeptide chains of secreted C4 indicate that pro-C4 and the C4 beta-chain have an identical amino acid sequence. Both molecules have lysine at position 1, leucine at positions 4, 5, and 6, and phenylalanine at position 7. No sequence homology was found between pro-C4 and either the alpha- or gamma-subunits. These results define the beta-chain as the NH2-terminal subunit in the C4 precursor molecules.