Evolution of Pathogenicity genes in Fusarium

Start date:
01 Jan 2013
End date:
31 Dec 2016
Researchers:
Matthew Laurence Candice Lim Liliana Rocha Brett Summerell Edward Liew
Project partners:
Robert Procter, Martyn Rep

Project aims

  • Determine if the Secreted In Xylem (SIX) pathogenicity gene family, recently discovered in the wilt pathogen Fusarium oxysporum, are present in other pathogenic and non-pathogenic Fusarium species. 
  • Determine if SIX gene orthologs are vertically transmitted from parent to offspring or through Horizontal Gene Transfer as recently documented in F. oxysporum.
  • Determine if SIX gene orthologs are under positive diversifying selection and where this has occurred within the Fusarium genus.

Project Summary

Fusarium oxysporum is among the ‘top ten’ plant pathogens of high socioeconomic significance.  Genomic sequencing has recently demonstrated the horizontal transfer of pathogenicity genes (SIX) between distantly related strains and marks a paradigm shift in that the evolution of pathogenicity genes rather than the evolution of the species is more critical for diagnostic marker development and to our understanding of the origin of new pathogens. This study investigates the diversity and distribution of SIX genes in the genus Fusarium, inferring their functionality through an analysis of positive diversifying selection.