title: Sex-linked transcriptional divergence in the hermaphrodite fungus Neurospora tetrasperma.
abstract: In the filamentous ascomycete Neurospora tetrasperma, a large (approx. 7 Mbp) region of suppressed recombination surrounds the mating-type (mat) locus. While the remainder of the genome is largely homoallelic, this region of recombinational suppression, extending over 1500 genes, is associated with sequence divergence. Here, we used microarrays to examine how the molecular phenotype of gene expression level is linked to this divergent region, and thus to the mating type. Culturing N. tetrasperma on agar media that induce sexual/female or vegetative/male tissue, we found 196 genes significantly differentially expressed between mat A and mat a mating types. Our data show that the genes exhibiting mat-linked expression are enriched in the region genetically linked to mating type, and sequence and expression divergence are positively correlated. Our results indicate that the phenotype of mat A strains is optimized for traits promoting sexual/female development and the phenotype of mat a strains for vegetative/male development. This discovery of differentially expressed genes associated with mating type provides a link between genotypic and phenotypic divergence in this taxon and illustrates a fungal analogue to sexual dimorphism found among animals and plants.
authors.affiliation: Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, PO Box 7026, 75007 Uppsala, Sweden.
authors.forename: Nicklas
authors.initials: N
authors.lastname: Samils
authors.forename: Anastasia
authors.initials: A
authors.lastname: Gioti
authors.forename: Magnus
authors.initials: M
authors.lastname: Karlsson
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.forename: Takao
authors.initials: T
authors.lastname: Kasuga
authors.forename: Eric
authors.initials: E
authors.lastname: Bastiaans
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Townsend
authors.forename: Hanna
authors.initials: H
authors.lastname: Johannesson
mesh_terms: D005075:Biological Evolution; D015825:Chromosomes, Fungal; D012734:Disorders of Sex Development; D015966:Gene Expression Regulation, Fungal; D049770:Genes, Mating Type, Fungal; D016681:Genome, Fungal; D009491:Neurospora / Q000235:genetics* / Q000502:physiology; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D011995:Recombination, Genetic
keywords: Neurospora tetrasperma; gene expression; sexual dimorphism