Structural and functional analysis of pp70S6k.

L Cheatham; M Monfar; M M Chou; J Blenis

doi:10.1073/pnas.92.25.11696

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Structural and functional analysis of pp70S6k.

L Cheatham·M Monfar·M M Chou·J Blenis

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Abstract

The pp70/85-kDa S6 kinases, collectively referred to as pp70S6k, are thought to participate in transit through the G1 phase of the cell cycle. pp70S6k regulates the phosphorylation of the 40S ribosomal protein S6 and the transcription factor CREM tau. pp70S6k is regulated by serine/threonine phosphorylation, and although 1-phosphatidylinositol 3-kinase and phospholipase C have been implicated as upstream regulators, the mechanism of activation and identity of the upstream pp70S6k kinases remain unknown. To improve our understanding of how this mitogen-stimulated protein kinase is regulated by growth factors and the immunosuppressant rapamycin, we have initiated a structure/function analysis of pp70S6k. Our results indicate that both the N and C termini participate in the complex regulation of pp70S6k activity.

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Androstadienes Animals Cells, Cultured Cricetinae DNA Mutational Analysis Drug Resistance Gene Expression Regulation, Enzymologic Immunosuppressive Agents Mutation Phosphorylation Polyenes Protein Serine-Threonine Kinases Ribosomal Protein S6 Kinases Sequence Deletion Sirolimus Wortmannin Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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L Cheatham, M Monfar, M M Chou, J Blenis. 1995-12-05. Structural and functional analysis of pp70S6k.. https://doi.org/10.1073/pnas.92.25.11696

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