title: Wall mechanics and exocytosis define the shape of growth domains in fission yeast.
abstract: The amazing structural variety of cells is matched only by their functional diversity, and reflects the complex interplay between biochemical and mechanical regulation. How both regulatory layers generate specifically shaped cellular domains is not fully understood. Here, we report how cell growth domains are shaped in fission yeast. Based on quantitative analysis of cell wall expansion and elasticity, we develop a model for how mechanics and cell wall assembly interact and use it to look for factors underpinning growth domain morphogenesis. Surprisingly, we find that neither the global cell shape regulators Cdc42-Scd1-Scd2 nor the major cell wall synthesis regulators Bgs1-Bgs4-Rgf1 are reliable predictors of growth domain geometry. Instead, their geometry can be defined by cell wall mechanics and the cortical localization pattern of the exocytic factors Sec6-Syb1-Exo70. Forceful re-directioning of exocytic vesicle fusion to broader cortical areas induces proportional shape changes to growth domains, demonstrating that both features are causally linked.
authors.affiliation: Genetics Department, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.|Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK.
authors.forename: Juan F
authors.initials: JF
authors.lastname: Abenza
authors.affiliation: Departamento de Física, Universidad de Santiago de Chile, Santiago, Chile.
authors.forename: Etienne
authors.initials: E
authors.lastname: Couturier
authors.affiliation: Genetics Department, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.|Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK.
authors.forename: James
authors.initials: J
authors.lastname: Dodgson
authors.affiliation: Genetics Department, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.|Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK.
authors.forename: Johanna
authors.initials: J
authors.lastname: Dickmann
authors.affiliation: Genetics Department, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.|Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK.
authors.forename: Anatole
authors.initials: A
authors.lastname: Chessel
authors.affiliation: Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Viña del Mar 2562307, Chile.|Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Avenue, Cambridge, Massachusetts 02138, USA.
authors.forename: Jacques
authors.initials: J
authors.lastname: Dumais
authors.affiliation: Genetics Department, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.|Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK.
authors.forename: Rafael E Carazo
authors.initials: REC
authors.lastname: Salas
mesh_terms: D001696:Biomechanical Phenomena; D002453:Cell Cycle; D002473:Cell Wall / Q000378:metabolism; D005089:Exocytosis; D008954:Models, Biological; D012568:Schizosaccharomyces / Q000254:growth & development* / Q000378:metabolism; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism
chemical_list: D020764:cdc42 GTP-Binding Protein