Okadaic acid-sensitive protein phosphatases dephosphorylate MARCKS, a major protein kinase C substrate

Paul R. Clarke, Suresh R. Siddhanti, Philip Cohen, Perry J. Blackshear

    Research output: Contribution to journalArticlepeer-review

    34 Citations (Scopus)

    Abstract

    The myristoylated alanine-rich C kinase substrate (MARCKS) undergoes a rapid and, in certain circumstances, transient increase in phosphorylation in response to stimuli that activate protein kinase C. We have investigated the protein-serine/threonine phosphatase activity responsible for reversing the phosphorylation of MARCKS. In cell-free assays, protein phosphatases 1, 2A and 2C (PP1, PP2A and PP2C) all dephosphorylate recombinant MARCKS or a synthetic peptide based on its phosphorylation site domain. In intact Swiss 3T3 cells, okadaic acid, a specific inhibitor of PP1 and PP2A, had little effect on MARCKS phosphorylation on its own, but largely prevented the dephosphorylation of MARCKS that occured following activation of protein kinase C by bombesin with subsequent receptor blockade. These results indicate that although the dephosphorylation of MARCKS can be mediated by PP2C in vitro, this protein is dephosphorylated by okadaic acid-sensitive phosphatases in the intact cell.

    Original languageEnglish
    Pages (from-to)37-42
    Number of pages6
    JournalFEBS Letters
    Volume336
    Issue number1
    DOIs
    Publication statusPublished - 20 Dec 1993

    Keywords

    • MARCKS
    • Okadaic acid
    • Protein kinase C
    • Protein phosphatase

    Fingerprint

    Dive into the research topics of 'Okadaic acid-sensitive protein phosphatases dephosphorylate MARCKS, a major protein kinase C substrate'. Together they form a unique fingerprint.

    Cite this