A myofibrillar protein phosphatase from rabbit skeletal muscle contains the β isoform of protein phosphatase-1 complexed to a regulatory subunit which greatly enhances the dephosphorylation of myosin

Paul Dent, Lindsay K. MacDougall, Carol MacKintosh, David G. Campbell, Philip Cohen

    Research output: Contribution to journalArticle

    48 Citations (Scopus)

    Abstract

    A form of protein phosphatase-1 (PP1M), which possesses 25-fold higher activity towards the P light chain of myosin (in heavy meromyosin) than other forms of protein phosphatase-1, was purified over 200000-fold from the myofibrillar fraction of rabbit skeletal muscle. PP1M, which eluted from Superose 12 with an apparent molecular mass of 60 kDa, was dissociated by LiBr into two subunits. One of these displayed enzymic properties identical to those of the catalytic subunit of protein phosphatase-1 (PP1C) and was identified as the beta isoform of PPI C by amino acid sequencing. The second subunit had no intrinsic protein phosphatase activity, but greatly increased the rate at which PP1C dephosphorylated skeletal-muscle heavy meromyosin and decreased the rate at which it dephosphorylated glycogen phosphorylase.

    The properties of PP1M, together with those of smooth muscle PP1M [Alessi, D., MacDougall, L. K., Sola, M. M., Ikebe, M. & Cohen, P. (1992) Eur. J. Biochem. 210,1023-10351 and the previously characterised glycogen-associated form of protein phosphatase-1 (PPI G), indicate that the subcellular localisation and substrate specificity of PPI is determined by its interaction with specific targetting subunits.

    Original languageEnglish
    Pages (from-to)1037-1044
    Number of pages8
    JournalEuropean Journal of Biochemistry
    Volume210
    Issue number3
    DOIs
    Publication statusPublished - 1992

    Cite this

    @article{e84eb48fe7e34914bf42176809525047,
    title = "A myofibrillar protein phosphatase from rabbit skeletal muscle contains the β isoform of protein phosphatase-1 complexed to a regulatory subunit which greatly enhances the dephosphorylation of myosin",
    abstract = "A form of protein phosphatase-1 (PP1M), which possesses 25-fold higher activity towards the P light chain of myosin (in heavy meromyosin) than other forms of protein phosphatase-1, was purified over 200000-fold from the myofibrillar fraction of rabbit skeletal muscle. PP1M, which eluted from Superose 12 with an apparent molecular mass of 60 kDa, was dissociated by LiBr into two subunits. One of these displayed enzymic properties identical to those of the catalytic subunit of protein phosphatase-1 (PP1C) and was identified as the beta isoform of PPI C by amino acid sequencing. The second subunit had no intrinsic protein phosphatase activity, but greatly increased the rate at which PP1C dephosphorylated skeletal-muscle heavy meromyosin and decreased the rate at which it dephosphorylated glycogen phosphorylase.The properties of PP1M, together with those of smooth muscle PP1M [Alessi, D., MacDougall, L. K., Sola, M. M., Ikebe, M. & Cohen, P. (1992) Eur. J. Biochem. 210,1023-10351 and the previously characterised glycogen-associated form of protein phosphatase-1 (PPI G), indicate that the subcellular localisation and substrate specificity of PPI is determined by its interaction with specific targetting subunits.",
    author = "Paul Dent and MacDougall, {Lindsay K.} and Carol MacKintosh and Campbell, {David G.} and Philip Cohen",
    year = "1992",
    doi = "10.1111/j.1432-1033.1992.tb17509.x",
    language = "English",
    volume = "210",
    pages = "1037--1044",
    journal = "European Journal of Biochemistry",
    issn = "0014-2956",
    publisher = "Wiley",
    number = "3",

    }

    TY - JOUR

    T1 - A myofibrillar protein phosphatase from rabbit skeletal muscle contains the β isoform of protein phosphatase-1 complexed to a regulatory subunit which greatly enhances the dephosphorylation of myosin

    AU - Dent, Paul

    AU - MacDougall, Lindsay K.

    AU - MacKintosh, Carol

    AU - Campbell, David G.

    AU - Cohen, Philip

    PY - 1992

    Y1 - 1992

    N2 - A form of protein phosphatase-1 (PP1M), which possesses 25-fold higher activity towards the P light chain of myosin (in heavy meromyosin) than other forms of protein phosphatase-1, was purified over 200000-fold from the myofibrillar fraction of rabbit skeletal muscle. PP1M, which eluted from Superose 12 with an apparent molecular mass of 60 kDa, was dissociated by LiBr into two subunits. One of these displayed enzymic properties identical to those of the catalytic subunit of protein phosphatase-1 (PP1C) and was identified as the beta isoform of PPI C by amino acid sequencing. The second subunit had no intrinsic protein phosphatase activity, but greatly increased the rate at which PP1C dephosphorylated skeletal-muscle heavy meromyosin and decreased the rate at which it dephosphorylated glycogen phosphorylase.The properties of PP1M, together with those of smooth muscle PP1M [Alessi, D., MacDougall, L. K., Sola, M. M., Ikebe, M. & Cohen, P. (1992) Eur. J. Biochem. 210,1023-10351 and the previously characterised glycogen-associated form of protein phosphatase-1 (PPI G), indicate that the subcellular localisation and substrate specificity of PPI is determined by its interaction with specific targetting subunits.

    AB - A form of protein phosphatase-1 (PP1M), which possesses 25-fold higher activity towards the P light chain of myosin (in heavy meromyosin) than other forms of protein phosphatase-1, was purified over 200000-fold from the myofibrillar fraction of rabbit skeletal muscle. PP1M, which eluted from Superose 12 with an apparent molecular mass of 60 kDa, was dissociated by LiBr into two subunits. One of these displayed enzymic properties identical to those of the catalytic subunit of protein phosphatase-1 (PP1C) and was identified as the beta isoform of PPI C by amino acid sequencing. The second subunit had no intrinsic protein phosphatase activity, but greatly increased the rate at which PP1C dephosphorylated skeletal-muscle heavy meromyosin and decreased the rate at which it dephosphorylated glycogen phosphorylase.The properties of PP1M, together with those of smooth muscle PP1M [Alessi, D., MacDougall, L. K., Sola, M. M., Ikebe, M. & Cohen, P. (1992) Eur. J. Biochem. 210,1023-10351 and the previously characterised glycogen-associated form of protein phosphatase-1 (PPI G), indicate that the subcellular localisation and substrate specificity of PPI is determined by its interaction with specific targetting subunits.

    U2 - 10.1111/j.1432-1033.1992.tb17509.x

    DO - 10.1111/j.1432-1033.1992.tb17509.x

    M3 - Article

    VL - 210

    SP - 1037

    EP - 1044

    JO - European Journal of Biochemistry

    JF - European Journal of Biochemistry

    SN - 0014-2956

    IS - 3

    ER -