title: Chitin synthase III: synthetic lethal mutants and "stress related" chitin synthesis that bypasses the CSD3/CHS6 localization pathway.
abstract: We screened Saccharomyces strains for mutants that are synthetically lethal with deletion of the major chitin synthase gene CHS3. In addition to finding, not surprisingly, that mutations in major cell wall-related genes such as FKS1 (glucan synthase) and mutations in any of the Golgi glycosylation complex genes (MNN9 family) are lethal in combination with chs3Delta, we found that a mutation in Srv2p, a bifunctional regulatory gene, is notably lethal in the chs3 deletion. In extending studies of fks1-chitin synthase 3 interactions, we made the surprising discovery that deletion of CSD3/CHS6, a gene normally required for Chs3p delivery and activity in vivo, was not lethal with fks1 and, in fact, that lack of Csd3p/Chs6p did not decrease the high level of stress-related chitin made in the fks1 mutant. This finding suggests that "stress response" chitin synthesis proceeds through an alternate Chs3p targeting pathway.
authors.affiliation: Center for Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: B C
authors.initials: BC
authors.lastname: Osmond
authors.forename: C A
authors.initials: CA
authors.lastname: Specht
authors.forename: P W
authors.initials: PW
authors.lastname: Robbins
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins / Q000235:genetics; D002473:Cell Wall / Q000737:chemistry; D002686:Chitin / Q000096:biosynthesis*; D002687:Chitin Synthase / Q000378:metabolism*; D003598:Cytoskeletal Proteins; D004058:Diffusion; D029721:Drosophila Proteins; D054714:Echinocandins; D005656:Fungal Proteins / Q000235:genetics; D005816:Genetic Complementation Test; D005964:Glucosyltransferases / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics; D008840:Microfilament Proteins; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C410502:Capt protein, Drosophila; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D029721:Drosophila Proteins; D054714:Echinocandins; D005656:Fungal Proteins; C086605:MNN9 protein, S cerevisiae; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D008840:Microfilament Proteins; C073751:SRV2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D002686:Chitin; D005964:Glucosyltransferases; D002687:Chitin Synthase; C020570:1,3-beta-glucan synthase; C091618:FKS1 protein, S cerevisiae