title: Phosphorylation of Gβ is crucial for efficient chemotropism in yeast.
abstract: Mating yeast cells interpret complex pheromone gradients and polarize their growth in the direction of the closest partner. Chemotropic growth depends on both the pheromone receptor and its associated G-protein. Upon activation by the receptor, Gα dissociates from Gβγ and Gβ is subsequently phosphorylated. Free Gβγ signals to the nucleus via a MAPK cascade and recruits Far1-Cdc24 to the incipient growth site. It is not clear how the cell establishes and stabilizes the axis of polarity, but this process is thought to require local signal amplification via the Gβγ-Far1-Cdc24 chemotropic complex, as well as communication between this complex and the activated receptor. Here we show that a mutant form of Gβ that cannot be phosphorylated confers defects in directional sensing and chemotropic growth. Our data suggest that phosphorylation of Gβ plays a role in localized signal amplification and in the dynamic communication between the receptor and the chemotropic complex, which underlie growth site selection and maintenance.
authors.affiliation: Laboratory for Molecular Biology, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
authors.forename: Reagan
authors.initials: R
authors.lastname: Deflorio
authors.forename: Marie-Elena
authors.initials: ME
authors.lastname: Brett
authors.forename: Nicholas
authors.initials: N
authors.lastname: Waszczak
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Apollinari
authors.forename: Metodi V
authors.initials: MV
authors.lastname: Metodiev
authors.forename: Oleksii
authors.initials: O
authors.lastname: Dubrovskyi
authors.forename: David
authors.initials: D
authors.lastname: Eddington
authors.forename: Robert A
authors.initials: RA
authors.lastname: Arkowitz
authors.forename: David E
authors.initials: DE
authors.lastname: Stone
mesh_terms: D000445:Aldehyde Oxidoreductases / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism; D016764:Cell Polarity / Q000235:genetics; D002633:Chemotaxis; D050756:Cyclin-Dependent Kinase Inhibitor Proteins / Q000378:metabolism; D044385:GTP-Binding Protein alpha Subunits / Q000378:metabolism*; D044387:GTP-Binding Protein beta Subunits / Q000235:genetics / Q000378:metabolism*; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000235:genetics; D009154:Mutation / Q000235:genetics; D010766:Phosphorylation / Q000235:genetics; D011485:Protein Binding; D043563:Receptors, Pheromone / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism
chemical_list: C073594:CDC24 protein, S cerevisiae; D018797:Cell Cycle Proteins; D050756:Cyclin-Dependent Kinase Inhibitor Proteins; C081353:FAR1 protein, S cerevisiae; D044385:GTP-Binding Protein alpha Subunits; D044387:GTP-Binding Protein beta Subunits; D020662:Guanine Nucleotide Exchange Factors; D043563:Receptors, Pheromone; D029701:Saccharomyces cerevisiae Proteins; D000445:Aldehyde Oxidoreductases
keywords: Chemotropism; Gβ phosphorylation; Polarized growth; Reorientation; Saccharomyces cerevisiae; Yeast mating response