Project description:The entomopathogen Metarhizium anisopliae contains strains with wide host ranges and specialist strains adapted to particular hosts. Patterns of gene duplication, divergence and deletion in three generalist and three specialist strains were investigated by heterologous hybridization of genomic DNA to genes from the generalist strain ARSEF 2575. Many sequences from 2575 that are highly conserved in fungi showed rapid evolution and loss in specialist Metarhizium genomes. Some poorly hybridizing genes in specialists were functionally coordinated, including several involved in toxin biosyntheses and sugar metabolism in root exudates, indicative of reductive evolution. This suggests that specialists are loosing genes required to live in alternative hosts or as saprophytes. Several components of mobile genetic elements were also highly divergent or lost in specialists. Exceptionally, the genome of the specialist strain ARSEF 443 contained extra insertion elements that might play a role in generating evolutionary novelty.
