ALBERT

Description: The fission yeast clade--comprising Schizosaccharomyces pombe, S. octosporus, S. cryophilus, and S. japonicus--occupies the basal branch of Ascomycete fungi and is an important model of eukaryote biology. A comparative annotation of these genomes identified a near extinction of transposons and the associated innovation of transposon-free centromeres. Expression analysis established that meiotic genes are subject to antisense transcription during vegetative growth, which suggests a mechanism for their tight regulation. In addition, trans-acting regulators control new genes within the context of expanded functional modules for meiosis and stress response. Differences in gene content and regulation also explain why, unlike the budding yeast of Saccharomycotina, fission yeasts cannot use ethanol as a primary carbon source. These analyses elucidate the genome structure and gene regulation of fission yeast and provide tools for investigation across the Schizosaccharomyces clade.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3131103/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3131103/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rhind, Nicholas -- Chen, Zehua -- Yassour, Moran -- Thompson, Dawn A -- Haas, Brian J -- Habib, Naomi -- Wapinski, Ilan -- Roy, Sushmita -- Lin, Michael F -- Heiman, David I -- Young, Sarah K -- Furuya, Kanji -- Guo, Yabin -- Pidoux, Alison -- Chen, Huei Mei -- Robbertse, Barbara -- Goldberg, Jonathan M -- Aoki, Keita -- Bayne, Elizabeth H -- Berlin, Aaron M -- Desjardins, Christopher A -- Dobbs, Edward -- Dukaj, Livio -- Fan, Lin -- FitzGerald, Michael G -- French, Courtney -- Gujja, Sharvari -- Hansen, Klavs -- Keifenheim, Dan -- Levin, Joshua Z -- Mosher, Rebecca A -- Muller, Carolin A -- Pfiffner, Jenna -- Priest, Margaret -- Russ, Carsten -- Smialowska, Agata -- Swoboda, Peter -- Sykes, Sean M -- Vaughn, Matthew -- Vengrova, Sonya -- Yoder, Ryan -- Zeng, Qiandong -- Allshire, Robin -- Baulcombe, David -- Birren, Bruce W -- Brown, William -- Ekwall, Karl -- Kellis, Manolis -- Leatherwood, Janet -- Levin, Henry -- Margalit, Hanah -- Martienssen, Rob -- Nieduszynski, Conrad A -- Spatafora, Joseph W -- Friedman, Nir -- Dalgaard, Jacob Z -- Baumann, Peter -- Niki, Hironori -- Regev, Aviv -- Nusbaum, Chad -- BB/E023754/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- DP1 OD003958/OD/NIH HHS/ -- R01 GM069957/GM/NIGMS NIH HHS/ -- R01 GM076396/GM/NIGMS NIH HHS/ -- R01 HG004037/HG/NHGRI NIH HHS/ -- U54 HG003067/HG/NHGRI NIH HHS/ -- U54 HG003067-06/HG/NHGRI NIH HHS/ -- Biotechnology and Biological Sciences Research Council/United Kingdom -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2011 May 20;332(6032):930-6. doi: 10.1126/science.1203357. Epub 2011 Apr 21.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA. nick.rhind@umassmed.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21511999" target="_blank"〉PubMed〈/a〉

Description: Wood is a major pool of organic carbon that is highly resistant to decay, owing largely to the presence of lignin. The only organisms capable of substantial lignin decay are white rot fungi in the Agaricomycetes, which also contains non-lignin-degrading brown rot and ectomycorrhizal species. Comparative analyses of 31 fungal genomes (12 generated for this study) suggest that lignin-degrading peroxidases expanded in the lineage leading to the ancestor of the Agaricomycetes, which is reconstructed as a white rot species, and then contracted in parallel lineages leading to brown rot and mycorrhizal species. Molecular clock analyses suggest that the origin of lignin degradation might have coincided with the sharp decrease in the rate of organic carbon burial around the end of the Carboniferous period.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Floudas, Dimitrios -- Binder, Manfred -- Riley, Robert -- Barry, Kerrie -- Blanchette, Robert A -- Henrissat, Bernard -- Martinez, Angel T -- Otillar, Robert -- Spatafora, Joseph W -- Yadav, Jagjit S -- Aerts, Andrea -- Benoit, Isabelle -- Boyd, Alex -- Carlson, Alexis -- Copeland, Alex -- Coutinho, Pedro M -- de Vries, Ronald P -- Ferreira, Patricia -- Findley, Keisha -- Foster, Brian -- Gaskell, Jill -- Glotzer, Dylan -- Gorecki, Pawel -- Heitman, Joseph -- Hesse, Cedar -- Hori, Chiaki -- Igarashi, Kiyohiko -- Jurgens, Joel A -- Kallen, Nathan -- Kersten, Phil -- Kohler, Annegret -- Kues, Ursula -- Kumar, T K Arun -- Kuo, Alan -- LaButti, Kurt -- Larrondo, Luis F -- Lindquist, Erika -- Ling, Albee -- Lombard, Vincent -- Lucas, Susan -- Lundell, Taina -- Martin, Rachael -- McLaughlin, David J -- Morgenstern, Ingo -- Morin, Emanuelle -- Murat, Claude -- Nagy, Laszlo G -- Nolan, Matt -- Ohm, Robin A -- Patyshakuliyeva, Aleksandrina -- Rokas, Antonis -- Ruiz-Duenas, Francisco J -- Sabat, Grzegorz -- Salamov, Asaf -- Samejima, Masahiro -- Schmutz, Jeremy -- Slot, Jason C -- St John, Franz -- Stenlid, Jan -- Sun, Hui -- Sun, Sheng -- Syed, Khajamohiddin -- Tsang, Adrian -- Wiebenga, Ad -- Young, Darcy -- Pisabarro, Antonio -- Eastwood, Daniel C -- Martin, Francis -- Cullen, Dan -- Grigoriev, Igor V -- Hibbett, David S -- New York, N.Y. -- Science. 2012 Jun 29;336(6089):1715-9. doi: 10.1126/science.1221748.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Biology Department, Clark University, Worcester, MA 01610, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22745431" target="_blank"〉PubMed〈/a〉

Description: The symbiosis between fungus-growing ants and the fungi they cultivate for food has been shaped by 50 million years of coevolution. Phylogenetic analyses indicate that this long coevolutionary history includes a third symbiont lineage: specialized microfungal parasites of the ants' fungus gardens. At ancient levels, the phylogenies of the three symbionts are perfectly congruent, revealing that the ant-microbe symbiosis is the product of tripartite coevolution between the farming ants, their cultivars, and the garden parasites. At recent phylogenetic levels, coevolution has been punctuated by occasional host-switching by the parasite, thus intensifying continuous coadaptation between symbionts in a tripartite arms race.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Currie, Cameron R -- Wong, Bess -- Stuart, Alison E -- Schultz, Ted R -- Rehner, Stephen A -- Mueller, Ulrich G -- Sung, Gi-Ho -- Spatafora, Joseph W -- Straus, Neil A -- New York, N.Y. -- Science. 2003 Jan 17;299(5605):386-8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA. ccurrie@ku.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12532015" target="_blank"〉PubMed〈/a〉

Description: Eucalypts are the world's most widely planted hardwood trees. Their outstanding diversity, adaptability and growth have made them a global renewable resource of fibre and energy. We sequenced and assembled 〉94% of the 640-megabase genome of Eucalyptus grandis. Of 36,376 predicted protein-coding genes, 34% occur in tandem duplications, the largest proportion thus far in plant genomes. Eucalyptus also shows the highest diversity of genes for specialized metabolites such as terpenes that act as chemical defence and provide unique pharmaceutical oils. Genome sequencing of the E. grandis sister species E. globulus and a set of inbred E. grandis tree genomes reveals dynamic genome evolution and hotspots of inbreeding depression. The E. grandis genome is the first reference for the eudicot order Myrtales and is placed here sister to the eurosids. This resource expands our understanding of the unique biology of large woody perennials and provides a powerful tool to accelerate comparative biology, breeding and biotechnology.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Myburg, Alexander A -- Grattapaglia, Dario -- Tuskan, Gerald A -- Hellsten, Uffe -- Hayes, Richard D -- Grimwood, Jane -- Jenkins, Jerry -- Lindquist, Erika -- Tice, Hope -- Bauer, Diane -- Goodstein, David M -- Dubchak, Inna -- Poliakov, Alexandre -- Mizrachi, Eshchar -- Kullan, Anand R K -- Hussey, Steven G -- Pinard, Desre -- van der Merwe, Karen -- Singh, Pooja -- van Jaarsveld, Ida -- Silva-Junior, Orzenil B -- Togawa, Roberto C -- Pappas, Marilia R -- Faria, Danielle A -- Sansaloni, Carolina P -- Petroli, Cesar D -- Yang, Xiaohan -- Ranjan, Priya -- Tschaplinski, Timothy J -- Ye, Chu-Yu -- Li, Ting -- Sterck, Lieven -- Vanneste, Kevin -- Murat, Florent -- Soler, Marcal -- Clemente, Helene San -- Saidi, Naijib -- Cassan-Wang, Hua -- Dunand, Christophe -- Hefer, Charles A -- Bornberg-Bauer, Erich -- Kersting, Anna R -- Vining, Kelly -- Amarasinghe, Vindhya -- Ranik, Martin -- Naithani, Sushma -- Elser, Justin -- Boyd, Alexander E -- Liston, Aaron -- Spatafora, Joseph W -- Dharmwardhana, Palitha -- Raja, Rajani -- Sullivan, Christopher -- Romanel, Elisson -- Alves-Ferreira, Marcio -- Kulheim, Carsten -- Foley, William -- Carocha, Victor -- Paiva, Jorge -- Kudrna, David -- Brommonschenkel, Sergio H -- Pasquali, Giancarlo -- Byrne, Margaret -- Rigault, Philippe -- Tibbits, Josquin -- Spokevicius, Antanas -- Jones, Rebecca C -- Steane, Dorothy A -- Vaillancourt, Rene E -- Potts, Brad M -- Joubert, Fourie -- Barry, Kerrie -- Pappas, Georgios J -- Strauss, Steven H -- Jaiswal, Pankaj -- Grima-Pettenati, Jacqueline -- Salse, Jerome -- Van de Peer, Yves -- Rokhsar, Daniel S -- Schmutz, Jeremy -- England -- Nature. 2014 Jun 19;510(7505):356-62. doi: 10.1038/nature13308. Epub 2014 Jun 11.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private bag X20, Pretoria 0028, South Africa [2] Genomics Research Institute (GRI), University of Pretoria, Private bag X20, Pretoria 0028, South Africa. ; 1] Laboratorio de Genetica Vegetal, EMBRAPA Recursos Geneticos e Biotecnologia, EPQB Final W5 Norte, 70770-917 Brasilia, Brazil [2] Programa de Ciencias Genomicas e Biotecnologia - Universidade Catolica de Brasilia SGAN 916, 70790-160 Brasilia, Brazil. ; 1] US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, California 94598, USA [2] Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. ; US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, California 94598, USA. ; HudsonAlpha Institute for Biotechnology, 601 Genome Way, Huntsville, Alabama 35801, USA. ; Bioinformatics and Computational Biology Unit, Department of Biochemistry, University of Pretoria, Pretoria, Private bag X20, Pretoria 0028, South Africa. ; Laboratorio de Bioinformatica, EMBRAPA Recursos Geneticos e Biotecnologia, EPQB Final W5 Norte, 70770-917 Brasilia, Brazil. ; Laboratorio de Genetica Vegetal, EMBRAPA Recursos Geneticos e Biotecnologia, EPQB Final W5 Norte, 70770-917 Brasilia, Brazil. ; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. ; Department of Plant Biotechnology and Bioinformatics (VIB), Ghent University, Technologiepark 927, B-9000 Ghent, Belgium. ; INRA/UBP UMR 1095, 5 Avenue de Beaulieu, 63100 Clermont Ferrand, France. ; Laboratoire de Recherche en Sciences Vegetales, UMR 5546, Universite Toulouse III, UPS, CNRS, BP 42617, 31326 Castanet Tolosan, France. ; 1] Bioinformatics and Computational Biology Unit, Department of Biochemistry, University of Pretoria, Pretoria, Private bag X20, Pretoria 0028, South Africa [2] Department of Botany, University of British Columbia, 3529-6270 University Blvd, Vancouver V6T 1Z4, Canada. ; Evolutionary Bioinformatics, Institute for Evolution and Biodiversity, University of Muenster, Huefferstrasse 1, D-48149, Muenster, Germany. ; 1] Evolutionary Bioinformatics, Institute for Evolution and Biodiversity, University of Muenster, Huefferstrasse 1, D-48149, Muenster, Germany [2] Department of Bioinformatics, Institute for Computer Science, University of Duesseldorf, Universitatsstrasse 1, 40225 Dusseldorf, Germany. ; Department of Forest Ecosystems and Society, Oregon State University, Corvallis, Oregon 97331, USA. ; 1] Department of Botany and Plant Pathology, Oregon State University, 2082-Cordley Hall, Corvallis, Oregon 97331, USA [2] Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon 97331, USA. ; Department of Botany and Plant Pathology, Oregon State University, 2082-Cordley Hall, Corvallis, Oregon 97331, USA. ; Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon 97331, USA. ; 1] Laboratorio de Biologia Evolutiva Teorica e Aplicada, Departamento de Genetica, Universidade Federal do Rio de Janeiro (UFRJ), Av. Prof. Rodolpho Paulo Rocco, 21949900 Rio de Janeiro, Brazil [2] Departamento de Biotecnologia, Escola de Engenharia de Lorena-Universidade de Sao Paulo (EEL-USP), CP116, 12602-810, Lorena-SP, Brazil [3] Laboratorio de Genetica Molecular Vegetal (LGMV), Departamento de Genetica, Universidade Federal do Rio de Janeiro (UFRJ), Av. Prof. Rodolpho Paulo Rocco, 21949900 Rio de Janeiro, Brazil. ; Laboratorio de Genetica Molecular Vegetal (LGMV), Departamento de Genetica, Universidade Federal do Rio de Janeiro (UFRJ), Av. Prof. Rodolpho Paulo Rocco, 21949900 Rio de Janeiro, Brazil. ; Research School of Biology, Australian National University, Canberra 0200, Australia. ; 1] Laboratoire de Recherche en Sciences Vegetales, UMR 5546, Universite Toulouse III, UPS, CNRS, BP 42617, 31326 Castanet Tolosan, France [2] IICT/MNE; Palacio Burnay - Rua da Junqueira, 30, 1349-007 Lisboa, Portugal [3] IBET/ITQB, Av. Republica, Quinta do Marques, 2781-901 Oeiras, Portugal. ; 1] IICT/MNE; Palacio Burnay - Rua da Junqueira, 30, 1349-007 Lisboa, Portugal [2] IBET/ITQB, Av. Republica, Quinta do Marques, 2781-901 Oeiras, Portugal. ; Arizona Genomics Institute, University of Arizona, Tucson, Arizona 85721, USA. ; Dep. de Fitopatologia, Universidade Federal de Vicosa, Vicosa 36570-000, Brazil. ; Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, Brazil. ; Science and Conservation Division, Department of Parks and Wildlife, Locked Bag 104, Bentley Delivery Centre, Western Australia 6983, Australia. ; GYDLE, 1363 av. Maguire, suite 301, Quebec, Quebec G1T 1Z2, Canada. ; Department of Environment and Primary Industries, Victorian Government, Melbourne, Victoria 3085, Australia. ; Melbourne School of Land and Environment, University of Melbourne, Melbourne, Victoria 3010, Australia. ; School of Biological Sciences and National Centre for Future Forest Industries, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia. ; 1] School of Biological Sciences and National Centre for Future Forest Industries, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia [2] Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Queensland 4558, Australia. ; 1] Genomics Research Institute (GRI), University of Pretoria, Private bag X20, Pretoria 0028, South Africa [2] Bioinformatics and Computational Biology Unit, Department of Biochemistry, University of Pretoria, Pretoria, Private bag X20, Pretoria 0028, South Africa. ; Departamento de Biologia Celular, Universidade de Brasilia, Brasilia 70910-900, Brazil. ; 1] Genomics Research Institute (GRI), University of Pretoria, Private bag X20, Pretoria 0028, South Africa [2] Department of Plant Biotechnology and Bioinformatics (VIB), Ghent University, Technologiepark 927, B-9000 Ghent, Belgium. ; 1] US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, California 94598, USA [2] HudsonAlpha Institute for Biotechnology, 601 Genome Way, Huntsville, Alabama 35801, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24919147" target="_blank"〉PubMed〈/a〉

Description: The effects of seasonal prescribed fire on the belowground ectomycorrhizal community and live fine root biomass were investigated before, 1 year after, and 2 years after prescribed underburning. Ectomycorrhizas were sampled from four replications of three treatments (fall underburning, spring underburning, and a nonburned control) in a randomized complete block design. Samples were separated in two subsamples representing the upper 5 cm and lower 5 cm of a soil core. Molecular tools were used to distinguish 140 restriction fragment length polymorphism (RFLP) species of fungi directly from the ectomycorrhizas. Prior to underburning, the number of RFLP species and amount of live root biomass were similar among treatment units and between upper and lower core samples. Fall underburning largely removed live root biomass to a depth of 10 cm and significantly reduced ectomycorrhizal species richness compared with spring underburning and the nonburned control for at least 2 years. RFLP species richness and live root biomass following spring underburning were generally similar to the nonburned treatment. The successful reintroduction of fire to the ecosystem to retain high species diversity of ectomycorrhizal fungi and achieve the desired future condition of large-tree ponderosa pine retention with low fuel loads may require more than underburning in a single season.

Description: As decomposers, fungi are key players in recycling plant material in global carbon cycles. We hypothesized that genomes of early diverging fungi may have inherited pectinases from an ancestral species that had been able to extract nutrients from pectin-containing land plants and their algal allies (Streptophytes). We aimed to infer, based on pectinase gene expansions and on the organismal phylogeny, the geological timing of the plant–fungus association. We analyzed 40 fungal genomes, three of which, including Gonapodya prolifera , were sequenced for this study. In the organismal phylogeny from 136 housekeeping loci, Rozella diverged first from all other fungi. Gonapodya prolifera was included among the flagellated, predominantly aquatic fungal species in Chytridiomycota. Sister to Chytridiomycota were the predominantly terrestrial fungi including zygomycota I and zygomycota II, along with the ascomycetes and basidiomycetes that comprise Dikarya. The Gonapodya genome has 27 genes representing five of the seven classes of pectin-specific enzymes known from fungi. Most of these share a common ancestry with pectinases from Dikarya. Indicating functional and sequence similarity, Gonapodya , like many Dikarya, can use pectin as a carbon source for growth in pure culture. Shared pectinases of Dikarya and Gonapodya provide evidence that even ancient aquatic fungi had adapted to extract nutrients from the plants in the green lineage. This implies that 750 million years, the estimated maximum age of origin of the pectin-containing streptophytes represents a maximum age for the divergence of Chytridiomycota from the lineage including Dikarya.

Description: Global declines in biodiversity are altering disease dynamics in complex and multifaceted ways. Changes in biodiversity can have several outcomes on disease risk, including dilution and amplification effects, both of which can have a profound influence on the effects of disease in a community. The dilution effect occurs when biodiversity and disease risk are inversely related, whereas the amplification effect is a positive relationship between biodiversity and disease risk. We tested these effects with an emerging fungal pathogen of amphibians, Batrachochytrium dendrobatidis (Bd), which is responsible for catastrophic amphibian population declines and extinctions worldwide. Despite the rapid and continued spread of Bd, the influence of host diversity on Bd dynamics remains unknown. We experimentally manipulated host diversity and density in the presence of Bd and found a dilution effect where increased species richness reduced disease risk, even when accounting for changes in density. These results demonstrate the general importance of incorporating community structure into studies of disease dynamics and have implications for the effects of Bd in ecosystems that differ in biodiversity.

Description: The ability of a fungus to infect novel hosts is dependent on changes in gene content, expression, or regulation. Examining gene expression under simulated host conditions can explore which genes may contribute to host jumping. Insect pathogenesis is the inferred ancestral character state for species of Tolypocladium , however several species are parasites of truffles, including Tolypocladium ophioglossoides . To identify potentially crucial genes in this interkingdom host switch, T. ophioglossoides was grown on four media conditions: media containing the inner and outer portions of its natural host (truffles of Elaphomyces ), cuticles from an ancestral host (beetle), and a rich medium (Yeast Malt). Through high-throughput RNASeq of mRNA from these conditions, many differentially expressed genes were identified in the experiment. These included PTH11-related G-protein-coupled receptors (GPCRs) hypothesized to be involved in host recognition, and also found to be upregulated in insect pathogens. A divergent chitinase with a signal peptide was also found to be highly upregulated on media containing truffle tissue, suggesting an exogenous degradative activity in the presence of the truffle host. The adhesin gene, Mad1 , was highly expressed on truffle media as well. A BiNGO analysis of overrepresented GO terms from genes expressed during each growth condition found that genes involved in redox reactions and transmembrane transport were the most overrepresented during T. ophioglossoides growth on truffle media, suggesting their importance in growth on fungal tissue as compared to other hosts and environments. Genes involved in secondary metabolism were most highly expressed during growth on insect tissue, suggesting that their products may not be necessary during parasitism of Elaphomyces . This study provides clues into understanding genetic mechanisms underlying the transition from insect to truffle parasitism.

Description: 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.