Recombination explains isochores in mammalian genomes.
The mouse Fxy gene was translocated into the highly recombining pseudoautosomal region comparatively recently in evolutionary terms. This event resulted in a rapid increase of GC content. We investigated the consequences of the translocation further by sequencing exons and introns of Fxy in various rodent species. We found that the DNA fragment newly located in a highly recombining context has acquired every property of a GC-rich isochore, namely increased GC content (especially at the third codon positions of exons), shorter introns and high density of minisatellites. These results strongly suggest that recombination is the primary determinant of the isochore organization of mammalian genomes.
Montoya-Burgos
Juan Ignacio
JI
CNRS UMR 5000-Génome, Populations, Interactions, Université Montpellier 2-CC63, Place E. Bataillon, 34095 Montpellier Cedex, France.
Boursot
Pierre
P
Galtier
Nicolas
N
D000818:Animals; D001482:Base Composition; D005075:Biological Evolution; D020862:GC Rich Sequence; D005796:Genes; D016678:Genome; D006801:Humans; D032085:Isochores / Q000737:chemistry / Q000235:genetics*; D018598:Minisatellite Repeats; D010802:Phylogeny; D011995:Recombination, Genetic; D013045:Species Specificity; D014178:Translocation, Genetic
D032085:Isochores