title: Identification of a complex genetic network underlying Saccharomyces cerevisiae colony morphology.
abstract: When grown on solid substrates, different microorganisms often form colonies with very specific morphologies. Whereas the pioneers of microbiology often used colony morphology to discriminate between species and strains, the phenomenon has not received much attention recently. In this study, we use a genome-wide assay in the model yeast Saccharomyces cerevisiae to identify all genes that affect colony morphology. We show that several major signalling cascades, including the MAPK, TORC, SNF1 and RIM101 pathways play a role, indicating that morphological changes are a reaction to changing environments. Other genes that affect colony morphology are involved in protein sorting and epigenetic regulation. Interestingly, the screen reveals only few genes that are likely to play a direct role in establishing colony morphology, with one notable example being FLO11, a gene encoding a cell-surface adhesin that has already been implicated in colony morphology, biofilm formation, and invasive and pseudohyphal growth. Using a series of modified promoters for fine-tuning FLO11 expression, we confirm the central role of Flo11 and show that differences in FLO11 expression result in distinct colony morphologies. Together, our results provide a first comprehensive look at the complex genetic network that underlies the diversity in the morphologies of yeast colonies.
authors.affiliation: Laboratory for Systems Biology, VIB, Bio-Incubator, Gaston Geenslaan 1, B-3001, Leuven, Belgium.
authors.forename: Karin
authors.initials: K
authors.lastname: Voordeckers
authors.forename: Dries
authors.initials: D
authors.lastname: De Maeyer
authors.forename: Elisa
authors.initials: E
authors.lastname: van der Zande
authors.forename: Marcelo D
authors.initials: MD
authors.lastname: Vinces
authors.forename: Wim
authors.initials: W
authors.lastname: Meert
authors.forename: Lore
authors.initials: L
authors.lastname: Cloots
authors.forename: Owen
authors.initials: O
authors.lastname: Ryan
authors.forename: Kathleen
authors.initials: K
authors.lastname: Marchal
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Verstrepen
mesh_terms: D015966:Gene Expression Regulation, Fungal; D053263:Gene Regulatory Networks; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development*; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis / Q000235:genetics; D015398:Signal Transduction; D013312:Stress, Physiological
chemical_list: C110690:FLO11 protein, S cerevisiae; D008562:Membrane Glycoproteins; D029701:Saccharomyces cerevisiae Proteins