Lehman D W, Putnam F W
Proc Natl Acad Sci U S A. 1980 Jun;77(6):3239-43. doi: 10.1073/pnas.77.6.3239.
The complete amino acid sequence of th variable (V) region of the mu heavy chain of a human IgM immunoglobulin (Cam) has been determined. The strategy for sequence determination involved sequenator analysis of the CNBr cleavage products of the succinylated carboxymethylated Fab mu fragment, and of tryptic peptides of the CNBr polypeptides and thermolytic subpeptides. The variable region of this heavy chain (VH) belongs to the VHIII subgroup; it has greater than 70% homology with other VHIII sequences and contains the VHIII marker peptide, Phe-Thr-Ile-Ser-Arg (residues 67-71). As more sequences have been published, the number of subgroup-specific residues has diminished to the point that no position is absolutely subgroup specific. An analysis of the available human VH sequences in the V/C switch region showed the likelihood of a human JH segment (residues 101-113) analogous to the J segments in mouse light chains. The JH region is highly conserved, has striking homology to proposed mouse JH regions, and has significant homology to known mouse J lambda and J kappa segments.
已确定一种人类IgM免疫球蛋白（Cam）的μ重链可变（V）区的完整氨基酸序列。序列测定策略包括对琥珀酰化羧甲基化Fabμ片段的CNBr裂解产物、CNBr多肽的胰蛋白酶肽段和热解亚肽段进行序列分析仪分析。该重链的可变区（VH）属于VHIII亚组；它与其他VHIII序列具有70%以上的同源性，并包含VHIII标记肽Phe-Thr-Ile-Ser-Arg（第67 - 71位残基）。随着更多序列的发表，亚组特异性残基的数量已减少到没有一个位置是绝对亚组特异性的程度。对V/C转换区中可用的人类VH序列的分析表明，存在一个类似于小鼠轻链中J片段的人类JH片段（第101 - 113位残基）的可能性。JH区域高度保守，与推测的小鼠JH区域具有显著同源性，并且与已知的小鼠Jλ和Jκ片段具有显著同源性。
