title: Transposable element-assisted evolution and adaptation to host plant within the Leptosphaeria maculans-Leptosphaeria biglobosa species complex of fungal pathogens.
abstract: BACKGROUND
  Many plant-pathogenic fungi have a tendency towards genome size expansion, mostly driven by increasing content of transposable elements (TEs). Through comparative and evolutionary genomics, five members of the Leptosphaeria maculans-Leptosphaeria biglobosa species complex (class Dothideomycetes, order Pleosporales), having different host ranges and pathogenic abilities towards cruciferous plants, were studied to infer the role of TEs on genome shaping, speciation, and on the rise of better adapted pathogens.
  
  
  RESULTS
  L. maculans 'brassicae', the most damaging species on oilseed rape, is the only member of the species complex to have a TE-invaded genome (32.5%) compared to the other members genomes (<4%). These TEs had an impact at the structural level by creating large TE-rich regions and are suspected to have been instrumental in chromosomal rearrangements possibly leading to speciation. TEs, associated with species-specific genes involved in disease process, also possibly had an incidence on evolution of pathogenicity by promoting translocations of effector genes to highly dynamic regions and thus tuning the regulation of effector gene expression in planta.
  
  
  CONCLUSIONS
  Invasion of L. maculans 'brassicae' genome by TEs followed by bursts of TE activity allowed this species to evolve and to better adapt to its host, making this genome species a peculiarity within its own species complex as well as in the Pleosporales lineage.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Grandaubert
authors.forename: Rohan G T
authors.initials: RG
authors.lastname: Lowe
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Soyer
authors.forename: Conrad L
authors.initials: CL
authors.lastname: Schoch
authors.forename: Angela P
authors.initials: AP
authors.lastname: Van de Wouw
authors.forename: Isabelle
authors.initials: I
authors.lastname: Fudal
authors.forename: Barbara
authors.initials: B
authors.lastname: Robbertse
authors.forename: Nicolas
authors.initials: N
authors.lastname: Lapalu
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Links
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Ollivier
authors.forename: Juliette
authors.initials: J
authors.lastname: Linglin
authors.forename: Valérie
authors.initials: V
authors.lastname: Barbe
authors.forename: Sophie
authors.initials: S
authors.lastname: Mangenot
authors.forename: Corinne
authors.initials: C
authors.lastname: Cruaud
authors.forename: Hossein
authors.initials: H
authors.lastname: Borhan
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Howlett
authors.forename: Marie-Hélène
authors.initials: MH
authors.lastname: Balesdent
authors.affiliation: INRA-Bioger, UR1290, Avenue Lucien Brétignières, BP 01, 78850 Thiverval-Grignon, France. rouxel@versailles.inra.fr.
authors.forename: Thierry
authors.initials: T
authors.lastname: Rouxel
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D001203:Ascomycota / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity / Q000502:physiology*; D015825:Chromosomes, Fungal / Q000235:genetics; D017124:Conserved Sequence / Q000235:genetics; D004251:DNA Transposable Elements / Q000235:genetics*; D019143:Evolution, Molecular; D005800:Genes, Fungal / Q000235:genetics; D023281:Genomics; D054884:Host-Pathogen Interactions; D005810:Multigene Family / Q000235:genetics; D010802:Phylogeny; D010944:Plants / Q000382:microbiology*; D013045:Species Specificity; D026801:Synteny / Q000235:genetics
chemical_list: D004251:DNA Transposable Elements