title: Phosphoinositides, exocytosis and polarity in yeast: all about actin?
abstract: Cell polarity is necessary for cell division, morphogenesis and motility in eukaryotes, and is determined by dynamic control of the cytoskeleton and secretory pathway to promote directional growth. In yeast, three essential and tightly-regulated processes orchestrate polarization and facilitate bud growth. These processes include phosphoinositide (PI) signaling, Rho GTPase regulation of the actin cytoskeleton, and exocytosis. As yet, the interplay between these different processes is unclear, and two main models (Spatial Landmark and Allosteric Local Activation) have been proposed for Rho GTPase control of polarization in yeast. Here, we summarize the inter-relationship between these growth processes and present a more unified model, the Exocytic Signal model, which proposes that exocytosis and actin regulation are fully integrated events mediated by PI signaling.
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Liat
authors.initials: L
authors.lastname: Yakir-Tamang
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Gerst
mesh_terms: D000199:Actins / Q000378:metabolism*; D016764:Cell Polarity; D005089:Exocytosis; D006801:Humans; D010716:Phosphatidylinositols / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D000199:Actins; D010716:Phosphatidylinositols