Complex history of the amphibian-killing chytrid fungus revealed with genome resequencing data

• Autores: Rosenblum, Erica Bree; James, Timothy Y.; Zamudio, Kelly R.; Poorten, Thomas J.; Ilut, Dan; Rodriguez, David; Eastman, Jonathan M.; Richards Hrdlicka, Katy; Joneson, Suzanne; Jenkinson, Thomas S.; Longcore, Joyce E.; Parra Olea, Gabriela; Toledo, Luis Felipe; Arellano, Maria Luz; Medina, Edgar M.; Restrepo, Silvia; Flechas, Sandra Victoria; Berger, Lee; Briggs, Cheryl J.; Stajich, Jason E.
• Año de publicación: 2013
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Batrachochytrium Dendrobatidis; Complex History; Genome Resequencing; Chytrid Fungus
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Understanding the evolutionary history of microbial pathogens is critical for mitigating the impacts of emerging infectious diseases on economically and ecologically important host species. We used a genome resequencing approach to resolve the evolutionary history of an important microbial pathogen, the chytrid Batrachochytrium dendrobatidis (Bd), which has been implicated in amphibian declines worldwide. We sequenced the genomes of 29 isolates of Bd from around the world, with an emphasis on North, Central, and South America because of the devastating effect that Bd has had on amphibian populations in the New World. We found a substantial amount of evolutionary complexity in Bd with deep phylogenetic diversity that predates observed global amphibian declines. By investigating the entire genome, we found that even the most recently evolved Bd clade (termed the global panzootic lineage) contained more genetic variation than previously reported. We also found dramatic differences among isolates and among genomic regions in chromosomal copy number and patterns of heterozygosity, suggesting complex and heterogeneous genome dynamics. Finally, we report evidence for selection acting on the Bd genome, supporting the hypothesis that protease genes are important in evolutionary transitions in this group. Bd is considered an emerging pathogen because of its recent effects on amphibians, but our data indicate that it has a complex evolutionary history that predates recent disease outbreaks. Therefore, it is important to consider the contemporary effects of Bd in a broader evolutionary context and identify specific mechanisms that may have led to shifts in virulence in this system.
Fil: Rosenblum, Erica Bree. University Of California Berkeley; Estados Unidos
Fil: James, Timothy Y.. University Of Michigan; Estados Unidos
Fil: Zamudio, Kelly R.. Cornell University; Estados Unidos
Fil: Poorten, Thomas J.. University Of California Berkeley; Estados Unidos
Fil: Ilut, Dan. Cornell University; Estados Unidos
Fil: Rodriguez, David. Cornell University; Estados Unidos
Fil: Eastman, Jonathan M.. University Of Idaho; Estados Unidos
Fil: Richards Hrdlicka, Katy. University Of Yale. Yale School Of Forestry & Environmental Studies; Estados Unidos
Fil: Joneson, Suzanne. University Of Idaho; Estados Unidos
Fil: Jenkinson, Thomas S.. University Of Michigan; Estados Unidos
Fil: Longcore, Joyce E.. University of Maine; Estados Unidos
Fil: Parra Olea, Gabriela. Universidad Nacional Autónoma de México; México
Fil: Toledo, Luis Felipe. Universidade Estadual de Campinas; Brasil
Fil: Arellano, Maria Luz. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Instituto de Botánica Spegazzini; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Medina, Edgar M.. Universidad de los Andes; Colombia
Fil: Restrepo, Silvia. Universidad de los Andes; Colombia
Fil: Flechas, Sandra Victoria. Universidad de los Andes; Colombia
Fil: Berger, Lee. James Cook University; Australia
Fil: Briggs, Cheryl J.. University of California; Estados Unidos
Fil: Stajich, Jason E.. University of California; Estados Unidos