Convergent evolution of chromosomal sex-determining regions in the animal and fungal kingdoms.

ABSTRACT: Sexual identity is governed by sex chromosomes in plants and animals, and by mating type (MAT) loci in fungi. Comparative analysis of the MAT locus from a species cluster of the human fungal pathogen Cryptococcus revealed sequential evolutionary events that fashioned this large, highly unusual region. We hypothesize that MAT evolved via four main steps, beginning with acquisition of genes into two unlinked sex-determining regions, forming independent gene clusters that then fused via chromosomal translocation. A transitional tripolar intermediate state then converted to a bipolar system via gene conversion or recombination between the linked and unlinked sex-determining regions. MAT was subsequently subjected to intra- and interallelic gene conversion and inversions that suppress recombina

SUBMITTER: Fraser JA 

PROVIDER: S-EPMC526376 | biostudies-literature | 2004 Dec

REPOSITORIES: biostudies-literature