Zds2p regulates Swe1p-dependent polarized cell growth in Saccharomyces cerevisiae via a novel Cdc55p interaction domain.
Deletion of the paralogs ZDS1 and ZDS2 in the budding yeast Saccharomyces cerevisiae causes a mis-regulation of polarized cell growth. Here we show a function for these genes as regulators of the Swe1p (Wee1p) kinase-dependent G2/M checkpoint. We identified a conserved domain in the C-terminus of Zds2p consisting of amino acids 813-912 (hereafter referred to as ZH4 for Zds homology 4) that is required for regulation of Swe1p-dependent polarized bud growth. ZH4 is shown by protein affinity assays to be necessary and sufficient for interaction with Cdc55p, a regulatory subunit of protein phosphatase 2A (PP2A). We hypothesized that the Zds proteins are in a pathway that negatively regulates the Swe1p-dependent G2/M checkpoint via Cdc55p. Supporting this model, deletion of CDC55 rescues the aberrant bud morphology of a zds1Δzds2Δ strain. We also show that expression of ZDS1 or ZDS2 from a strong galactose-inducible promoter can induce mitosis even when the Swe1p-dependent G2/M checkpoint is activated by mis-organization of the actin cytoskeleton. This negative regulation requires the CDC55 gene. Together these data indicate that the Cdc55p/Zds2p module has a function in the regulation of the Swe1p-dependent G2/M checkpoint.
Yasutis
Kimberly
K
Departments of Biology and Cell Biology, University of Virginia, Charlottesville, VA 22904, USA.
Vignali
Marissa
M
Ryder
Matthew
M
Tameire
Feven
F
Dighe
Shubha A
SA
Fields
Stanley
S
Kozminski
Keith G
KG
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D017124:Conserved Sequence; D016195:G2 Phase; D017353:Gene Deletion; D008938:Mitosis; D020125:Mutation, Missense; D010766:Phosphorylation; D025941:Protein Interaction Mapping; D054648:Protein Phosphatase 2 / Q000235:genetics / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors
D048868:Adaptor Proteins, Signal Transducing; C071246:CDC55 protein, S cerevisiae; D018797:Cell Cycle Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; C101740:ZDS1 protein, S cerevisiae; C101741:ZDS2 protein, S cerevisiae; C099685:SWE1 protein, S cerevisiae; D011505:Protein-Tyrosine Kinases; D054648:Protein Phosphatase 2