Domain structures and molecular evolution of class I and class II major histocompatibility gene complex (MHC) products deduced from amino acid and nucleotide sequence homologies |
| |
Authors: | Koji Ohnishi |
| |
Institution: | (1) Department of Biology, Faculty of Science, Niigata University, 950-21 Niigata, Japan |
| |
Abstract: | Domain structures of class I and class II MHC products were analyzed from a viewpoint of amino acid and nucleotide sequence homologies. Alignment statistics revealed that class I (transplantation) antigen H chains consist of four mutually homologous domains, and that class II (HLA-DR) antigen and chains are both composed of three mutually homologous ones. The N-terminal three and two domains of class I and class II (both and ) gene products, respectively, all of which being 90 residues long, were concluded to be homologous to 2-microglobulin ( 2M). The membraneembedded C-terminal shorter domains of these MHC products were also found to be homologous to one another and to the third domain of class I H chains. Class I H chains were found to be more closely related to class II chains than to class II chains. Based on these findings, an exon duplication history from a common ancestral gene encoding a 2M-like primodial protein of one-domain-length up to the contemporary MHC products was proposed. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|