Open AccessProtein Phosphatase Type 1-Interacting Protein Ysw1 Is Involved in Proper Septin Organization and Prospore Membrane Formation during Sporulation
Author(s) -
Makoto Ishihara,
Yuji Suda,
Ichiro Inoue,
Takayuki Tanaka,
Tetsuo Takahashi,
XiaoDong Gao,
Yoshinori Fukui,
Sayoko Ihara,
Aaron M. Neiman,
Hiroyuki Tachikawa
Publication year - 2009
Publication title -
eukaryotic cell
Language(s) - English
Resource type - Journals
eISSN - 1535-9778
pISSN - 1535-9786
DOI - 10.1128/ec.00095-09
Subject(s) - septin , biology , phosphatase , protein subunit , protein phosphatase 2 , saccharomyces cerevisiae , microbiology and biotechnology , protein phosphatase 1 , membrane protein , cytokinesis , biochemistry , membrane , cell division , yeast , cell , phosphorylation , gene
Sporulation ofSaccharomyces cerevisiae is a developmental process in which four haploid spores are generated inside a diploid cell. Gip1, a sporulation-specific targeting subunit of protein phosphatase type 1, together with its catalytic subunit, Glc7, colocalizes with septins along the extending prospore membrane and is required for septin organization and spore wall formation. However, the mechanism by which Gip1-Glc7 phosphatase promotes these events is unclear. We show here that Ysw1, a sporulation-specific coiled-coil protein, has a functional relationship to Gip1-Glc7 phosphatase. Overexpression ofYSW1 partially suppresses the sporulation defect of a temperature-sensitive allele ofgip1 . Ysw1 interacts with Gip1 in a two-hybrid assay, and this interaction is required for suppression. Ysw1 tagged with green fluorescent protein colocalizes with septins and Gip1 along the extending prospore membrane during spore formation. Sporulation is partially defective inysw1 Δ mutant, and cytological analysis revealed that septin structures are perturbed and prospore membrane extension is aberrant inysw1 Δ cells. These results suggest that Ysw1 functions with the Gip1-Glc7 phosphatase to promote proper septin organization and prospore membrane formation.