Campus Units

Animal Science

Document Type

Article

Publication Version

Published Version

Publication Date

11-29-2016

Journal or Book Title

Proceedings of the National Academy of Sciences

Volume

113

Issue

48

First Page

13815

Last Page

13820

DOI

10.1073/pnas.1616948113

Abstract

Defensins constitute an evolutionary conserved family of cationic antimicrobial peptides that play a key role in host innate immune responses to infection. Defensin genes generally reside in complex genomic regions that are prone to structural variation, and defensin genes exhibit extensive copy number variation in humans and in other species. Copy number variation of defensin genes was examined in inbred lines of Leghorn and Fayoumi chickens, and a duplication of defensin7 was discovered in the Fayoumi breed. Analysis of junction sequences confirmed the occurrence of a simple tandem duplication of defensin7 with sequence identity at the junction, suggesting nonallelic homologous recombination between defensin7 and defensin6. The duplication event generated two chimeric promoters that are best explained by gene conversion followed by homologous recombination. Expression of defensin7 was not elevated in animals with two genes despite both genes being transcribed in the tissues examined. Computational prediction of promoter regions revealed the presence of several putative transcription factor binding sites generated by the duplication event. These data provide insight into the evolution and possible function of large gene families and specifically, the defensins.

Comments

This article is published as Lee, Mi Ok, Susanne Bornelöv, Leif Andersson, Susan J. Lamont, Junfeng Chen, and James E. Womack. "Duplication of chicken defensin7 gene generated by gene conversion and homologous recombination." Proceedings of the National Academy of Sciences 113, no. 48 (2016): 13815-13820. DOI: 10.1073/pnas.1616948113. Posted with permission.

Copyright Owner

The Author(s)

Language

en

File Format

application/pdf

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