RT Journal Article
SR Electronic
T1 Large X-linked palindromes undergo arm-to-arm gene conversion across Mus lineages
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 800185
DO 10.1101/800185
A1 Callie M. Swanepoel
A1 Emma R. Gerlinger
A1 Jacob L. Mueller
YR 2019
UL http://biorxiv.org/content/early/2019/10/10/800185.abstract
AB Large (>10kb), nearly-identical (>99% nucleotide identity), palindromic sequences are enriched on mammalian sex chromosomes. Primate Y-palindromes undergo high rates of arm-to-arm gene conversion, a proposed mechanism for maintaining their sequence integrity in the absence of X-Y recombination. It is unclear whether X-palindromes, which can freely recombine in females, undergo arm-to-arm gene conversion and, if so, at what rate. We generated high-quality sequence assemblies of Mus molossinus and Mus spretus X-palindromic regions and compared them to orthologous Mus musculus X-palindromes. Our evolutionary sequence comparisons found evidence of X-palindrome arm-to-arm gene conversion at rates comparable to rates of autosomal allelic gene conversion in mice. Mus X-palindrome genes also exhibit higher than expected sequence diversification, indicating gene conversion may facilitate the rapid evolution of palindrome-associated genes. We conclude that in addition to maintaining genes’ sequence integrity via sequence homogenization, arm-to-arm gene conversion can also rapidly drive genetic evolution via sequence diversification.