Grosmannia clavigera

The ophiostomatoid fungus Grosmannia clavigera (anamorph: Leptographium clavigerum) is a haploid filamentous ascomycetes and a symbiont of the bark beetle Dendroctonus ponderosae (MPB), which is a native beetle of western North American pine forests. MPB outbreaks affect not only commercial conifer species but also parks, protected areas and urban forests. The current epidemic has killed lodgepole pine trees across more than 16 million hectares of British Columbia. The beetle's ophiostomatoid associates colonize the phloem and sapwood of conifers, causing a blue/black discoloration. The discoloration arises from the deep pigmentation of fungal hyphae resulting from the accumulation of DHN-melanin. G. clavigera grows under limited oxygen conditions in the tree and on relatively simple media in the laboratory. A gene knockout system using Agrobacterium tumefaciens transformation system is available to confirm gene function in G. clavigera and to support research to understand the mechanisms underpinning the bark beetle-fungal-conifer interaction. The Grosmannia clavigera genome is sequenced as part of a research program to understand the relationship between the fungus, beetle and host tree and to clarify how the fungus grows in pine despite the tree defense chemicals. This is the first ophiostomatoid fungus to have its genome sequenced. Grosmannia clavigera genome is approximately 30 Mb.

The Tria Project

The Tria Project led by the Michael Smith Laboratories at UBC and BCCA Genome Sciences Centre sequenced the ~30 Mb genome of Grosmannia clavigera strain kw1407 at ~60X coverage using a hybrid whole genome shotgun (WGS) sequencing method. WGS projects ACXQ00000000 and ACYC00000000 are assembled from the same sequence reads using different methodologies. For ACXQ00000000 (Sanger-454-IlluminaPA) raw Illumina PE reads were assembled using Velvet, and 454 and Sanger reads were assembled with Forge. The two sets of contigs were then combined. For ACYC00000000 (Sanger-454-IlluminaDA) there was no pre-assembly. Filtered genomic DNA reads from Sanger, 454 and Illumina were assembled using the Forge genome assembler.