期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1972
卷号：69
期号：7
页码：1697-1701
DOI：10.1073/pnas.69.7.1697
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Analysis of the primary structure of {beta}2-microglobulin indicates that this human protein is homologous in sequence to the constant portion of immunoglobulin light chains (CL), and to the homology regions (CH1, CH2, and CH3) of the constant portion of {gamma}1 (heavy) chains of immunoglobulin G. Homology with the CH3 region is particularly striking. No convincing homology could be demonstrated by similar comparisons with the variable regions of immunoglobulin light and heavy chains. {beta}2-Microglobulin contains an intrachain disulfide loop of 57 amino-acid residues that is similar in size to disulfide loops found in the constant regions of immunoglobulin G. These findings suggest that {beta}2-microglobulin is a free immunoglobulin domain, possibly serving an effector function similar to that of the CH3 domain of {gamma}1 chains of immunoglobulin G.
