Isochores and effectors : genome reshaping and the birth of highly pathogenic species in fungal phytopathogens

The apple scab agent Venturia inaequalis and the stem canker of oilseed rape agent Leptosphaeria maculans represent economically important diseases. Both behave as invasive species and show an extremely high evolutionary potential. FungIsochores aims to provide a generic scheme to understand how and when an invasive species may arise from a less-damaging and less-adapted species, and how rapidly it can then adapt to specific selection pressures (e.g. those imposed by the environment and host) to improve its competitiveness. With the advent of genomics, and the sequencing of numerous fungal genomes, genome structure and species-specific genes, both being closely interconnected in a series of fungal species, are now suggested to be instrumental to explain genome plasticity and adaptability of fungi to changing environment. On these bases, the proposed basic research project aims to exploit and gain novel whole-genome knowledge by de novo sequencing and annotation of the genome of V. inaequalis and (ii) de novo sequencing of three species/subspecies of the L. maculans-L. biglobosa species complex. This novel knowledge will be used to derive information on invasion by transposable element (TE), its impact on genome structure and the birth of isochores, and birth/evolution of pathogenicity effectors.