Unknown

Dataset Information

0

Duplication and selection in the evolution of primate beta-defensin genes.


ABSTRACT: BACKGROUND:Innate immunity is the first line of defense against microorganisms in vertebrates and acts by providing an initial barrier to microorganisms and triggering adaptive immune responses. Peptides such as beta-defensins are an important component of this defense, providing a broad spectrum of antimicrobial activity against bacteria, fungi, mycobacteria and several enveloped viruses. Beta-defensins are small cationic peptides that vary in their expression patterns and spectrum of pathogen specificity. Disruptions in beta-defensin function have been implicated in human diseases, including cystic fibrosis, and a fuller understanding of the variety, function and evolution of human beta-defensins might form the basis for novel therapies. Here we use a combination of laboratory and computational techniques to characterize the main human beta-defensin locus on chromosome 8p22-p23. RESULTS:In addition to known genes in the region we report the genomic structures and expression patterns of four novel human beta-defensin genes and a related pseudogene. These genes show an unusual pattern of evolution, with rapid divergence between second exon sequences that encode the mature beta-defensin peptides matched by relative stasis in first exons that encode signal peptides. CONCLUSIONS:We conclude that the 8p22-p23 locus has evolved by successive rounds of duplication followed by substantial divergence involving positive selection, to produce a diverse cluster of paralogous genes established before the human-baboon divergence more than 23 million years ago. Positive selection, disproportionately favoring alterations in the charge of amino-acid residues, is implicated as driving second exon divergence in these genes.

SUBMITTER: Semple CA 

PROVIDER: S-EPMC156587 | biostudies-literature | 2003

REPOSITORIES: biostudies-literature

altmetric image

Publications

Duplication and selection in the evolution of primate beta-defensin genes.

Semple Colin A M CA   Rolfe Mark M   Dorin Julia R JR  

Genome biology 20030417 5


<h4>Background</h4>Innate immunity is the first line of defense against microorganisms in vertebrates and acts by providing an initial barrier to microorganisms and triggering adaptive immune responses. Peptides such as beta-defensins are an important component of this defense, providing a broad spectrum of antimicrobial activity against bacteria, fungi, mycobacteria and several enveloped viruses. Beta-defensins are small cationic peptides that vary in their expression patterns and spectrum of p  ...[more]

Similar Datasets

| S-EPMC1156880 | biostudies-literature
| S-EPMC1464053 | biostudies-literature
| S-EPMC4018336 | biostudies-literature
| S-EPMC2875236 | biostudies-literature
| S-EPMC2943986 | biostudies-literature
| S-EPMC4571063 | biostudies-other
| S-EPMC3684511 | biostudies-literature
| S-EPMC2873416 | biostudies-literature
| S-EPMC6098084 | biostudies-literature
| S-EPMC1262708 | biostudies-literature