Sak, a murine protein-serine/threonine kinase that is related to the Drosophila polo kinase and involved in cell proliferation.
We have isolated murine cDNAs encoding two isoforms of a putative protein-serine/threonine kinase, designated Sak-a and Sak-b, which differ in their noncatalytic C-terminal ends. The kinase domain of Sak is related to the catalytic domains of the Drosophila polo, Saccharomyces cerevisiae CDC5, and murine Snk and Plk kinases, a family of proteins for which a role in controlling cell proliferation has been established (polo, CDC5) or implicated (Snk, Plk). Northern and in situ RNA analyses of Sak gene expression in mouse embryos and adult tissues revealed that expression was associated with mitotic and meiotic cell division. In addition, during embryogenesis, Sak expression was prominent in the respiratory and olfactory mucosa. The pattern of Sak expression and its sequence homology with the polo gene family suggest that the Sak kinase may play a role in cell proliferation. In support of this, cell growth was suppressed by expression of a Sak-a-antisense fragment in CHO cells.
Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON Canada.
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Fode
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Heffernan
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D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins; D002455:Cell Division; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000378:metabolism; D004330:Drosophila / Q000201:enzymology*; D029721:Drosophila Proteins; D005314:Embryonic and Fetal Development; D005656:Fungal Proteins / Q000096:biosynthesis / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D017403:In Situ Hybridization; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D009928:Organ Specificity; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis* / Q000378:metabolism; D016601:RNA-Binding Proteins; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
C513239:CEF1 protein, S cerevisiae; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005656:Fungal Proteins; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; C088051:Plk4 protein, mouse; C072004:polo protein, Drosophila; D017346:Protein Serine-Threonine Kinases