Résumé
Well known for its potential for industrial applications detailed in other chapters of this book, Yarrowia lipolytica occupies an interesting position among hemiascomycetous yeasts due to its basal position in the phylum associated with profound physiological differences setting it apart from the model species, Saccharomyces cerevisiae. Its study may thus shed light both on the history of yeast genomes and on the emergence of new solutions invented by yeasts to carry out basic functions like chromosome maintenance or mating in this highly diversified but phylogenetically coherent group. This chapter will give an overview of the data accumulated by the Génolevures consortium on the genome of Y. lipolytica. Since its first release in 2004, this genome appeared deeply different in terms of structure, gene content and organisation from that of other known hemiascomycetes. The message told by this unusual yeast genome was however difficult to understand fully for lack of intermediates providing a link to other genomes and of closely related genomes to sort out idiosyncrasies from ancestral characteristics. The recent publication of the genome of Pichia pastoris, a distantly related species but also deep branching, as well as our ongoing work on species closely related to Y. lipolytica (the “Y. lipolytica clade”) or on a third deep branching species, Arxula adeninivorans, begins to fill some holes and may help building of an integrated view of yeast genome evolution.