Prdm9 polymorphism unveils mouse evolutionary tracks.
PR/SET domain containing 9 (Prdm9) mediates histone modifications such as H3K4me3 and marks hotspots of meiotic recombination. In many mammalian species, the Prdm9 gene is highly polymorphic. Prdm9 polymorphism is assumed to play two critical roles in evolution: to diversify the spectrum of meiotic recombination hotspots and to cause male hybrid sterility, leading to reproductive isolation and speciation. Nevertheless, information about Prdm9 sequences in natural populations is very limited. In this study, we conducted a comprehensive population survey on Prdm9 polymorphism in the house mouse, Mus musculus. Overall M. musculus Prdm9 displays an extraordinarily high level of polymorphism, particularly in regions encoding zinc finger repeats, which recognize recombination hotspots. Prdm9 alleles specific to various M. musculus subspecies dominate in subspecies territories. Moreover, introgression into other subspecies territories was found for highly divergent Prdm9 alleles associated with t-haplotype. The results of our phylogeographical analysis suggest that the requirement for hotspot diversity depends on geographical range and time span in mouse evolution, and that Prdm9 polymorphism has not been maintained by a simple balanced selection in the population of each subspecies.
Mammalian Genetics Laboratory, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan Department of Biophysics and Biochemistry, The University of Tokyo, Tokyo 153-8902, Japan.
Hiromitsu
H
Kono
Mammalian Genetics Laboratory, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan.
Masaru
M
Tamura
Division of Evolutionary Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.
Naoki
N
Osada
Laboratory of Ecology and Genetics, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
Hitoshi
H
Suzuki
BioResource Center, RIKEN Tsukuba Institute, Tsukuba, Ibaraki 305-0074, Japan.
Kuniya
K
Abe
BioResource Center, RIKEN Tsukuba Institute, Tsukuba, Ibaraki 305-0074, Japan.
Kazuo
K
Moriwaki
Department of Biophysics and Biochemistry, The University of Tokyo, Tokyo 153-8902, Japan Department of Life Sciences, The University of Tokyo, Tokyo 153-8902, Japan.
Kunihiro
K
Ohta
Mammalian Genetics Laboratory, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan tshirois@lab.nig.ac.jp.
Toshihiko
T
Shiroishi
D000595:Amino Acid Sequence; D000818:Animals; D033481:Chromosomes, Mammalian; D019143:Evolution, Molecular; D006239:Haplotypes; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics*; D051379:Mice / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D058974:Phylogeography; D011110:Polymorphism, Genetic; D013045:Species Specificity; D016335:Zinc Fingers
D011495:Histone-Lysine N-Methyltransferase; C534829:prdm9 protein, mouse
Prdm9; evolution; mouse; polymorphism