Wurentuya Jaiseng, Yue Fang, Yan Ma, Reiko Sugiura, Takayoshi Kuno
Division of Molecular Pharmacology and Pharmacogenomics, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Japan.
PloS one 2012We previously identified Cis4, a zinc transporter belonging to the cation diffusion facilitator protein family, and we demonstrated that Cis4 is implicated in Golgi membrane trafficking in fission yeast. Here, we identified three glycosylphosphatidylinositol (GPI)-anchored proteins, namely Ecm33, Aah3, and Gaz2, as multicopy suppressors of the MgCl(2)-sensitive phenotype of cis4-1 mutant. The phenotypes of ecm33, aah3 and gaz2 deletion cells were distinct from each other, and Cis4 overexpression suppressed Δecm33 phenotypes but did not suppress Δaah3 defects. Notably, green fluorescent protein-tagged Ecm33, which was observed at the cell surface in wild-type cells, mostly localized as intracellular dots that are presumed to be the Golgi and endosomes in membrane-trafficking mutants, including Δapm1, ypt3-i5, and chc1-1 mutants. Interestingly, all these membrane-trafficking mutants showed hypersensitivity to BE49385A, an inhibitor of Its8 that is involved in GPI-anchored protein synthesis. Taken together, these results suggest that GPI-anchored proteins are transported through a clathrin-mediated post-Golgi membrane trafficking pathway and that zinc transporter Cis4 may play roles in membrane trafficking of GPI-anchored proteins in fission yeast.
Wurentuya Jaiseng, Yue Fang, Yan Ma, Reiko Sugiura, Takayoshi Kuno. Studies on the roles of clathrin-mediated membrane trafficking and zinc transporter Cis4 in the transport of GPI-anchored proteins in fission yeast. PloS one. 2012;7(7):e41946
PMID: 22848669
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