Title

Evolution of murine alpha 1-proteinase inhibitors: gene amplification and reactive center divergence

ISBN or ISSN

0022-2844

Publication Title

Journal of molecular evolution

Volume

38

Issue

2

Publication Date / Copyright Date

2-1-1994

First Page

121

Last Page

131

Publisher

Springer-Verlag.

DOI Number

10.1007/BF00166159

Abstract

The organization and sequence of genes encoding the alpha 1-proteinase inhibitor (alpha 1PI), a major serine proteinase inhibitor of the mammalian bloodstream, have been compared in several species, including murine rodents (genus Mus). Analysis of gene copy number indicates that amplification of alpha 1PI genes occurred at some time during evolution of the Mus genus, leading to fixation of a family of about three to five genes in several existing species (e.g., M. domesticus and M. saxicola), and only a single gene in others (e.g., M. caroli). A phylogeny for the various mammalian alpha 1PI mRNAs was constructed based upon synonymous substitutions within coding regions. The mRNAs in different murine species diverged from a common ancestor before the formation of the first species lineages of the Mus genus, i.e., about 10-13 million years ago. Thus, alpha 1PI gene amplification must have occurred prior to Mus speciation; gene families were retained in some, but not all, murine species. The reactive center region of the alpha 1PI polypeptide, which determines target protease specificity, has diverged rapidly during evolution of the Mus species, but not during evolution of other mammalian species included in the analysis. It is likely that this accelerated evolution of the reactive center, which has been noted previously for serine proteinase inhibitors, was driven by some sort of a positive Darwinian selection that was exerted in a taxon-specific manner. We suggest that evolution of alpha 1PI genes of murine rodents has been characterized by both modification of gene copy number and rapid reactive center divergence. These processes may have resulted in a broadened repertoire of proteinase inhibitors that was evolutionarily advantageous during Mus speciation.

Disciplines

Medicine and Health Sciences | Pharmacy and Pharmaceutical Sciences

Keywords

Amino Acid Sequence, Animals, Base Sequence, Biological Evolution, Cloning, Molecular, DNA Probes, Gene Amplification, Gene Library, Genetic Variation, Mice, Molecular Sequence Data, Multigene Family, Muridae, RNA, Messenger, Sequence Alignment, Sequence Analysis, DNA, Species Specificity, alpha 1-Antitrypsin

This document is currently not available here.

Peer Reviewed

Find in your library

Share

 
COinS