An AGC kinase, PgAGC1 regulates virulence in the entomopathogenic oomycete Pythium guiyangense.

Mosquitoes are the most important medical species by transmitting some of deadly infectious diseases to human. In recent years extensive studies of vector control have been focused on biological control agents due to the grave issue raised by continuous application of chemical compounds. Pythium guiyangense X.Q. Su was first isolated from infected larvae of Aedes albopictus in 2006 in China and it has been proven to be a promising mosquito control agent. However, the molecular mechanisms of this oomycete pathogenic to mosquitoes are still not clear. In this study, we identified a new gene from the genome of P. guiyangense, PgAGC1 that belongs to the AGC kinase group and we found that the transcriptional expression levels of this gene were significantly up-regulated during infection of mosquito Culex pipiens pallens. Disruption of the PgAGC1gene via genetic transformation methods affects colony growth and stress responses and results in reduced mortality and infection rates. All the evidence revealed that, besides its role in growth and stress resistance, PgAGC1 is putative determinants of P. guiyangense virulence. The results of this study become of particular importance in understanding the mechanisms of oomycete-mosquito interactions.