FIG. 8.

Structural comparison of the C. neoformans mating-type alleles. (A) Comparison of the α and a mating-type alleles of serotype D for analysis of the relative positions of the genes found within and adjacent to the MAT locus. Vertical and diagonal lines connect diverged gene alleles present in both alleles and illustrate substantial gene rearrangements within the MAT locus, whereas gene order outside the MAT locus has been conserved. In addition, a few genes that are present in only one of the two MAT alleles were identified (white arrows). (B) Comparison of the α mating-type alleles between serotypes A and D. Similar to what occurred in the α and a alleles from serotype D, significant rearrangements of gene order have occurred in the α allele during strain divergence (vertical and diagonal lines), and some genes are unique to one serotype (white arrows). Interestingly, the IKS1 gene flanks the MAT locus in serotype D but is located within the locus in serotype A. For additional details, see the legend to Fig. 1.