| Title: | Comparative Genomics of the Ectomycorrhizal Sister Species Rhizopogon vinicolor and Rhizopogon vesiculosus (Basidiomycota: Boletales) Reveals a Divergence of the Mating Type B Locus |
| Author(s): | Mujic AB; Kuo A; Tritt A; Lipzen A; Chen C; Johnson J; Sharma A; Barry K; Grigoriev IV; Spatafora JW; |
| Address: | "Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331 amujic@gmail.com. Joint Genome Institute, United States Department of Energy, Walnut Creek, California 95458. Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331" |
| ISSN/ISBN: | 2160-1836 (Electronic) 2160-1836 (Linking) |
| Abstract: | "Divergence of breeding system plays an important role in fungal speciation. Ectomycorrhizal fungi, however, pose a challenge for the study of reproductive biology because most cannot be mated under laboratory conditions. To overcome this barrier, we sequenced the draft genomes of the ectomycorrhizal sister species Rhizopogon vinicolor Smith and Zeller and R. vesiculosus Smith and Zeller (Basidiomycota, Boletales)-the first genomes available for Basidiomycota truffles-and characterized gene content and organization surrounding their mating type loci. Both species possess a pair of homeodomain transcription factor homologs at the mating type A-locus as well as pheromone receptor and pheromone precursor homologs at the mating type B-locus. Comparison of Rhizopogon genomes with genomes from Boletales, Agaricales, and Polyporales revealed synteny of the A-locus region within Boletales, but several genomic rearrangements across orders. Our findings suggest correlation between gene content at the B-locus region and breeding system in Boletales with tetrapolar species possessing more diverse gene content than bipolar species. Rhizopogon vinicolor possesses a greater number of B-locus pheromone receptor and precursor genes than R. vesiculosus, as well as a pair of isoprenyl cysteine methyltransferase genes flanking the B-locus compared to a single copy in R. vesiculosus Examination of dikaryotic single nucleotide polymorphisms within genomes revealed greater heterozygosity in R. vinicolor, consistent with increased rates of outcrossing. Both species possess the components of a heterothallic breeding system with R. vinicolor possessing a B-locus region structure consistent with tetrapolar Boletales and R. vesiculosus possessing a B-locus region structure intermediate between bipolar and tetrapolar Boletales" |
| Keywords: | "Basidiomycota/classification/*genetics Chromosome Mapping Computational Biology/methods *Genes, Mating Type, Fungal *Genome, Fungal Genome-Wide Association Study *Genomics/methods Genotype High-Throughput Nucleotide Sequencing Mutation Mycorrhizae/classif;" |
| Notes: | "MedlineMujic, Alija Bajro Kuo, Alan Tritt, Andrew Lipzen, Anna Chen, Cindy Johnson, Jenifer Sharma, Aditi Barry, Kerrie Grigoriev, Igor V Spatafora, Joseph W eng Research Support, U.S. Gov't, Non-P.H.S. England 2017/04/30 G3 (Bethesda). 2017 Jun 7; 7(6):1775-1789. doi: 10.1534/g3.117.039396" |
