RRC ID 874
著者 Cortés JC, Carnero E, Ishiguro J, Sánchez Y, Durán A, Ribas JC.
タイトル The novel fission yeast (1,3)beta-D-glucan synthase catalytic subunit Bgs4p is essential during both cytokinesis and polarized growth.
ジャーナル J Cell Sci
Abstract Schizosaccharomyces pombe contains four putative (1,3)beta-D-glucan synthase (GS) catalytic subunits, Bgs1p-4p. In this work, we cloned bgs4+ and show that Bgs4p is the only subunit found to be a part of the GS enzyme and essential for maintaining cell integrity during cytokinesis and polarized growth. Here we show that bgs4+, cwg1+ (cwg1-1 shows reduced cell-wall beta-glucan and GS catalytic activity) and orb11+ (orb11-59 is defective in cell morphogenesis) are the same gene. bgs4+ is essential for spore germination and bgs4+ shut-off produces cell lysis at growing poles and mainly at the septum prior to cytokinesis, suggesting that Bgs4p is essential for cell wall growth and to compensate for an excess of cell wall degradation during cytokinesis. Shut-off and overexpression analysis suggest that Bgs4p forms part of a GS catalytic multiprotein complex and that Bgs4p-promoted cell-wall beta-glucan alterations induce compensatory mechanisms from other Bgs subunits and (1,3)alpha-D-glucan synthase. Physiological localization studies showed that Bgs4p localizes to the growing ends, the medial ring and septum, and at each stage of wall synthesis or remodeling that occurs during sexual differentiation: mating, zygote and spore formation, and spore germination. Bgs4p timing and requirements for proper positioning during cytokinesis and its localization pattern during spore maturation differ from those of Bgs1p. Bgs4p localizes overlapping the contractile ring once Bgs1p is present and a Calcofluor white-stained septum material is detected, suggesting that Bgs4p is involved in a late process of secondary or general septum synthesis. Unlike Bgs1p, Bgs4p needs the medial ring but not the septation initiation network proteins to localize with the other septation components. Furthermore, Bgs4p localization depends on the polarity establishment proteins. Finally, F-actin is necessary for Bgs4p delocalization from and relocalization to the growing regions, but it is not needed for the stable maintenance of Bgs4p at the growing sites, poles and septum. All these data show for the first time an essential role for a Bgs subunit in the synthesis of a (1,3)beta-D-glucan necessary to preserve cell integrity when cell wall synthesis or repair are needed.
巻・号 118(Pt 1)
ページ 157-74
公開日 2005-1-1
DOI 10.1242/jcs.01585
PII 118/1/157
PMID 15615781
MeSH Catalytic Domain / genetics* Cell Polarity / genetics* Cell Wall / enzymology Cytokinesis / genetics* Gene Deletion Glucosyltransferases / chemistry* Microscopy, Confocal Protein Subunits / genetics Protein Subunits / metabolism Schizosaccharomyces / enzymology Schizosaccharomyces / genetics Schizosaccharomyces pombe Proteins*
IF 4.573
引用数 85
WOS 分野 CELL BIOLOGY
リソース情報
酵母