Mammalian phosphatidylinositol 3'-kinase induces a lethal phenotype on expression in Schizosaccharomyces pombe; comparison with the VPS34 gene product.
The 110-kDa catalytic subunit of the phosphatidylinositol 3'-kinase (p110) is shown to be expressed in Schizosaccharomyces pombe as a functional protein, as judged by the accumulation of 3'-phosphorylated lipids in vivo and the extraction of 3'-kinase activity in vitro. On expression of p110, the cells fail to grow and lose viability. In contrast, while the Saccharomyces cerevisiae protein Vps34p can be expressed in S. pombe as a functional, extractable, phosphatidylinositol 3-kinase, expression of this protein fails to increase substantially 3'-phosphorylated lipids in vivo and does not induce a phenotype equivalent to that induced by p110. The results indicate that (over-)-accumulation of 3'-phosphorylated inositol lipids in S. pombe causes loss of viability.
Kodaki
T
T
Protein Phosphorylation Laboratory, Imperial Cancer Research Fund, London, England.
Woscholski
R
R
Emr
S
S
Waterfield
M D
MD
Nurse
P
P
Parker
P J
PJ
D002455:Cell Division; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003001:Cloning, Molecular; D003470:Culture Media; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics; D005800:Genes, Fungal; D050356:Lipid Metabolism; D008856:Microscopy, Fluorescence; D010641:Phenotype; D019869:Phosphatidylinositol 3-Kinases; D010766:Phosphorylation; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000096:biosynthesis* / Q000235:genetics; D010957:Plasmids; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development
D003470:Culture Media; D005656:Fungal Proteins; D019869:Phosphatidylinositol 3-Kinases; D017853:Phosphotransferases (Alcohol Group Acceptor)