Dynamic linkage relationships to the mating-type locus in automictic fungi of the genus Microbotryum.
Regions of the chromosomes determining mating compatibility in some fungi, including Microbotryum lychnidis-dioicae and Neurospora tetrasperma, exhibit suppressed recombination similar to sex chromosomes in plants and animals, and recent studies have sought to apply basic theories of sex chromosome evolution to fungi. A phylogeny of the MTL1 locus in Microbotryum indicates that it has become part of the nonrecombining regions of the mating-type chromosomes in multiple independent events, and that recombination may have been subsequently restored in some cases. This illustrates that fungal mating-type chromosomes can exhibit linkage relationship that are quite dynamic, adding to the list of similarities to animal or plant sex chromosomes. However, fungi such as M. lychnidis-dioicae and N. tetrasperma exhibit an automictic mating system, for which an alternate theoretical framework exists to explain the evolution of linkage with the mating-type locus. This study encourages further comparative studies among fungi to evaluate the role of mating systems in determining the evolution of fungal mating-type chromosomes.
Abbate
J L
JL
Department of Biology, University of Virginia, Charlottesville, VA, USA.
Hood
M E
ME
D001487:Basidiomycota / Q000166:cytology / Q000235:genetics*; D005800:Genes, Fungal / Q000235:genetics*; D049770:Genes, Mating Type, Fungal / Q000235:genetics*; D008040:Genetic Linkage; D008969:Molecular Sequence Data; D010802:Phylogeny