Phylogeny of Leptographium Qinlingensis Cytochrome P450 Genes and Their Expression When Grown on Different Media or Treated With Terpenoids

Abstract

Leptographium qinlingensis is a fungal associate of the Chinese white pine beetle (Dendroctonus armandi) and a pathogen of the Chinese white pine (Pinus armandi) that must overcome the terpenoid oleoresin defences of host trees. We identified and phylogenetically analysed the cytochrome P450 (CYP) genes in the transcriptome of L. qinlingensis. Through analyses of the growth rates on different nutritional media and inhibition by terpenoids, the expression profiles of six CYPs in the mycelium of L. qinlingensis grown on different media or treated with terpenoids were determined. The CYP evolution predicted that most of the CYPs occurred in a putative common ancestor shared between L. qinlingensis and G. clavigera. This fungus is symbiotic with D. armandi and has more similarity with G. clavigera, which can retrieve nutrition from pine wood and utilize monoterpenes as the sole carbon source. Some CYP genes might be involved in the metabolism of fatty acids and detoxification of terpenes and phenolics, as observed in other blue-stained fungi, which also indicates the pathogenic properties of L. qinlingensis in Chinese white pine.