Compartmentalization of the cell cortex by septins is required for maintenance of cell polarity in yeast.
Formation and maintenance of specialized plasma membrane domains are crucial for many biological processes, such as cell polarization and signaling. During isotropic bud growth, the yeast cell periphery is divided into two domains: the bud surface, an active site of exocytosis and growth, and the relatively quiescent surface of the mother cell. We found that cells lacking septins at the bud neck failed to maintain the exocytosis and morphogenesis factors Spa2, Sec3, Sec5, and Myo2 in the bud during isotropic growth. Furthermore, we found that septins were required for proper regulation of actin patch stability; septin-defective cells permitted to enter isotropic growth lost actin and growth polarity. We propose that septins maintain cell polarity by specifying a boundary between cortical domains.
Barral
Y
Y
Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520, USA.
Mermall
V
V
Mooseker
M S
MS
Snyder
M
M
D000199:Actins / Q000302:isolation & purification; D002352:Carrier Proteins / Q000302:isolation & purification; D002451:Cell Compartmentation; D018797:Cell Cycle Proteins; D002455:Cell Division / Q000502:physiology; D002462:Cell Membrane / Q000648:ultrastructure; D016764:Cell Polarity; D003593:Cytoplasm / Q000648:ultrastructure; D003598:Cytoskeletal Proteins; D005089:Exocytosis; D005656:Fungal Proteins / Q000302:isolation & purification*; D009024:Morphogenesis; D018995:Myosin Heavy Chains; D024462:Myosin Type II; D024701:Myosin Type V; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000648:ultrastructure*; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins
D000199:Actins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins; C077512:MYO2 protein, S cerevisiae; C434211:MYO2 protein, S pombe; C103130:SEC3 protein, S cerevisiae; C103131:SEC5 protein, S cerevisiae; C065889:SPA2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C099685:SWE1 protein, S cerevisiae; D011505:Protein-Tyrosine Kinases; D024462:Myosin Type II; D024701:Myosin Type V; D018995:Myosin Heavy Chains