Molecular and Cellular Biochemistry

, Volume 259, Issue 1–2, pp 197–209 | Cite as

Myosin phosphatase: Structure, regulation and function

  • Masaaki Ito
  • Takeshi Nakano
  • Ferenc Erdődi
  • David J. Hartshorne


Phosphorylation of myosin II plays an important role in many cell functions, including smooth muscle contraction. The level of myosin II phosphorylation is determined by activities of myosin light chain kinase and myosin phosphatase (MP). MP is composed of 3 subunits: a catalytic subunit of type 1 phosphatase, PP1c; a targeting subunit, termed myosin phosphatase target subunit, MYPT; and a smaller subunit, M20, of unknown function. Most of the properties of MP are due to MYPT and include binding of PP1c and substrate. Other interactions are discussed. A recent discovery is the existence of an MYPT family and members include, MYPT1, MYPT2, MBS85, MYPT3 and TIMAP. Characteristics of each are outlined. An important discovery was that the activity of MP could be regulated and both activation and inhibition were reported. Activation occurs in response to elevated cyclic nucleotide levels and various mechanisms are presented. Inhibition of MP is a major component of Ca2+-sensitization in smooth muscle and various molecular mechanisms are discussed. Two mechanisms are cited frequently: (1) Phosphorylation of an inhibitory site on MYPT1, Thr696 (human isoform) and resulting inhibition of PP1c activity. Several kinases can phosphorylate Thr696, including Rho-kinase that serves an important role in smooth muscle function; and (2) Inhibition of MP by the protein kinase C-potentiated inhibitor protein of 17 kDa (CPI-17). Examples where these mechanisms are implicated in smooth muscle function are presented. The critical role of RhoA/Rho-kinase signaling in various systems is discussed, in particular those vascular smooth muscle disorders involving hypercontractility.

myosin phosphatase type 1 phosphatase MYPT1 Rho Rho-kinase CPI-17 smooth muscle Ca2+ sensitization cGMP-dependent protein kinase 


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  1. 1.
    Hartshorne DJ: Biochemistry of the contractile process in smooth muscle. In: L.R. Johnson (eds). Physiology of the Gastrointestinal Tract. Raven Press, New York, 1987, pp 432-482Google Scholar
  2. 2.
    Somlyo AP, Somlyo AV: Signal transduction and regulation in smooth muscle. Nature 372: 231-236, 1994CrossRefPubMedGoogle Scholar
  3. 3.
    Somlyo AP, Somlyo AV: Signal transduction by G-proteins, Rho-kinase and protein phosphatase to smooth muscle and non-muscle myosin II. J Physiol 522: 177-185, 2000CrossRefPubMedGoogle Scholar
  4. 4.
    Wu X, Somlyo AV, Somlyo AP: Cyclic GMP-dependent stimulation reverses G-protein-coupled inhibition of smooth muscle myosin light chain phosphate. Biochem Biophys Res Commun 220: 658-663, 1996CrossRefPubMedGoogle Scholar
  5. 5.
    Lee MR, Li L, Kitazawa T: Cyclic GMP causes Ca2+ desensitization in vascular smooth muscle by activating the myosin light chain phosphatase. J Biol Chem 272: 5063-5068, 1997CrossRefPubMedGoogle Scholar
  6. 6.
    Alessi D, MacDougall LK, Sola MM, Ikebe M, Cohen P: The control of protein phosphatase-1 by targetting subunits. The major myosin phosphatase in avian smooth muscle is a novel form of protein phosphatase-1. Eur J Biochem 210: 1023-1035, 1992CrossRefPubMedGoogle Scholar
  7. 7.
    Hartshorne DJ, Ito M, Erdődi F: Myosin light chain phosphatase: Subunit composition, interactions and regulation. J Muscle Res Cell Motil 19: 325-341, 1998CrossRefPubMedGoogle Scholar
  8. 8.
    Machida H, Ito M, Okamoto R, Shiraki K, Isaka N, Hartshorne DJ, Nakano T: Molecular cloning and analysis of the 5′-flanking region of the human MYPT1 gene. Biochim Biophys Acta 1517: 424-429, 2001PubMedGoogle Scholar
  9. 9.
    Okubo S, Ito M, Takashiba Y, Ichikawa K, Miyahara M, Shimizu H, Konishi T, Shima H, Nagao M, Hartshorne DJ, Nakano T: A regulatory subunit of smooth muscle myosin bound phosphatase. Biochem Biophys Res Commun 200: 429-434, 1994CrossRefPubMedGoogle Scholar
  10. 10.
    Boudrez A, Evens K, Beullens M, Waelkens E, Stalmans W, Bollen M: Identification of MYPT1 and NIPP1 as subunits of protein phosphatase 1 in rat liver cytosol. FEBS Lett 455: 175-178, 1999CrossRefPubMedGoogle Scholar
  11. 11.
    Takahashi N, Ito M, Tanaka J, Nakano T, Kaibuchi K, Odai H, Takemura K: Localization of the gene coding for myosin phosphatase, target subunit 1 (MYPT1) to human chromosome 12q15-q21. Genomics 44: 150-152, 1997CrossRefPubMedGoogle Scholar
  12. 12.
    Dirksen WP, Vladic F, Fisher SA: A myosin phosphatase targeting subunit isoform transition defines a smooth muscle developmental phenotypic switch. Am J Physiol Cell Physiol 278: C589-C600, 2000PubMedGoogle Scholar
  13. 13.
    Shimizu H, Ito M, Miyahara M, Ichikawa K, Okubo S, Konishi T, Naka M, Tanaka T, Hirano K, Hartshorne DJ, Nakano T: Characterization of the myosin-binding subunit of smooth muscle myosin phosphatase. J Biol Chem 269: 30407-30411, 1994PubMedGoogle Scholar
  14. 14.
    Richards CT, Ogut O, Brozovich FV, Richards CT, Ogut O, Brozovich FV: Agonist-induced force enhancement: The role of isoforms and phosphorylation of the myosin-targeting subunit of myosin light chain phosphatase. J Biol Chem 277: 4422-4427, 2002CrossRefPubMedGoogle Scholar
  15. 15.
    Johnson D, Cohen P, Chen MX, Chen YH, Cohen PT: Identification of the regions on the M110 subunit of protein phosphatase 1M that interact with the M21 subunit and with myosin. Eur J Biochem 244: 931-939, 1997CrossRefPubMedGoogle Scholar
  16. 16.
    Khatri JJ, Joyce KM, Brozovich FV, Fisher SA: Role of myosin phosphatase isoforms in cGMP-mediated smooth muscle relaxation. J Biol Chem 276: 37250-37257, 2001CrossRefPubMedGoogle Scholar
  17. 17.
    Ichikawa K, Hirano K, Ito M, Tanaka J, Nakano T, Hartshorne DJ: Interactions and properties of smooth muscle myosin phosphatase. Biochemistry 35: 6313-6320, 1996CrossRefPubMedGoogle Scholar
  18. 18.
    Hirano K, Phan BC, Hartshorne DJ: Interactions of the subunits of smooth muscle myosin phosphatase. J Biol Chem 272: 3683-3688, 1997CrossRefPubMedGoogle Scholar
  19. 19.
    Tanaka J, Ito M, Feng J, Ichikawa K, Hamaguchi T, Nakamura M, Hartshorne DJ, Nakano T: Interaction of myosin phosphatase target subunit 1 with the catalytic subunit of type 1 protein phosphatase. Biochemistry 37: 16697-16703, 1998CrossRefPubMedGoogle Scholar
  20. 20.
    Tóth A, Kiss E, Gergely P, Walsh MP, Hartshorne DJ, Erdödi F: Phosphorylation of MYPT1 by protein kinase C attenuates interaction with PP1 catalytic subunit and the 20 kDa light chain of myosin. FEBS Lett 484: 113-117, 2000CrossRefPubMedGoogle Scholar
  21. 21.
    Velasco G, Armstrong C, Morrice N, Frame S, Cohen P: Phosphorylation of the regulatory subunit of smooth muscle protein phosphatase 1 M at Thr850 induces its dissociation from myosin. FEBS Lett 527: 101-104, 2002CrossRefPubMedGoogle Scholar
  22. 22.
    Kimura K, Ito M, Amano M, Chihara K, Fukata Y, Nakafuku M, Yamamori B, Feng J, Nakano T, Okawa K, Iwamatsu A, Kaibuchi K: Regulation of myosin phosphatase by Rho and Rho-associated kinase (Rho-kinase). Science 273: 245-248, 1996PubMedGoogle Scholar
  23. 23.
    Surks HK, Mochizuki N, Kasai Y, Georgescu SP, Tang KM, Ito M, Lincoln TM, Mendelsohn ME: Regulation of myosin phosphatase by a specific interaction with cGMP-dependent protein kinase Iα. Science 286: 1583-1587, 1999CrossRefPubMedGoogle Scholar
  24. 24.
    Ito M, Feng J, Tsujino S, Inagaki N, Inagaki M, Tanaka J, Ichikawa K, Hartshorne DJ, Nakano T: Interaction of smooth muscle myosin phosphatase with phospholipids. Biochemistry 36: 7607-7614, 1997CrossRefPubMedGoogle Scholar
  25. 25.
    Inagaki N, Nishizawa M, Ito M, Fujioka M, Nakano T, Tsujino S, Matsuzawa K, Kimura K, Kaibuchi K, Inagaki M: Myosin binding subunit of smooth muscle myosin phosphatase at the cell-cell adhesion sites in MDCK cells. Biochem Biophys Res Commun 230: 552-556, 1997CrossRefPubMedGoogle Scholar
  26. 26.
    Hirano M, Niiro N, Hirano K, Nishimura J, Hartshorne DJ, Kanaide H: Expression, subcellular localization, and cloning of the 130-kDa regulatory subunit of myosin phosphatase in porcine aortic endothelial cells. Biochem Biophys Res Commun 254: 490-496, 1999CrossRefPubMedGoogle Scholar
  27. 27.
    Fujioka M, Takahashi N, Odai H, Araki S, Ichikawa K, Feng J, Nakamura M, Kaibuchi K, Hartshorne DJ, Nakano T, Ito M: A new isoform of human myosin phosphatase targeting/regulatory subunit (MYPT2): cDNA cloning, tissue expression, and chromosomal mapping. Genomics 49: 59-68, 1998CrossRefPubMedGoogle Scholar
  28. 28.
    Tan I, Ng CH, Lim L, Leung T: Phosphorylation of a novel myosin binding subunit of protein phosphatase 1 reveals a conserved mechanism in the regulation of actin cytoskeleton. J Biol Chem 276: 21209-21216, 2001CrossRefPubMedGoogle Scholar
  29. 29.
    Skinner JA, Saltiel AR: Cloning and identification of MYPT3: A prenylatable myosin targetting subunit of protein phosphatase 1. Biochem J 356: 257-267, 2001CrossRefPubMedGoogle Scholar
  30. 30.
    Cao W, Mattagajasingh SN, Xu H, Kim K, Fierlbeck W, Deng J, Lowenstein CJ, Ballermann BJ: TIMAP, a novel CAAX box protein regulated by TGF-β1 and expressed in endothelial cells. Am J Physiol Cell Physiol 283: C327-C337, 2002PubMedGoogle Scholar
  31. 31.
    Arimura T, Suematsu N, Zhou YB, Nishimura J, Satoh S, Takeshita A, Kanaide H, Kimura A: Identification, characterization, and functional analysis of heart-specific myosin light chain phosphatase small subunit. J Biol Chem 276: 6073-6082, 2001CrossRefPubMedGoogle Scholar
  32. 32.
    Moorhead G, Johnson D, Morrice N, Cohen P: The major myosin phosphatase in skeletal muscle is a complex between the β-isoform of protein phosphatase 1 and the MYPT2 gene product. FEBS Lett 438: 141-144, 1998CrossRefPubMedGoogle Scholar
  33. 33.
    Chen YH, Chen MX, Alessi DR, Campbell DG, Shanahan C, Cohen P, Cohen PT: Molecular cloning of cDNA encoding the 110 and 21 kDa regulatory subunits of smooth muscle protein phosphatase 1 M. FEBS Lett 356: 51-55, 1994CrossRefPubMedGoogle Scholar
  34. 34.
    Mabuchi K, Gong BJ, Langsetmo K, Ito M, Nakano T, Tao T: Isoforms of the small non-catalytic subunit of smooth muscle myosin light chain phosphatase. Biochim Biophys Acta 1434: 296-303, 1999PubMedGoogle Scholar
  35. 35.
    Takizawa N, Schmidt DJ, Mabuchi K, Villa-Moruzzi E, Tuft RA, Ikebe M: M20, the small subunit of PP1M, binds to microtubules. Am J Physiol Cell Physiol 284: C250-C262, 2003PubMedGoogle Scholar
  36. 36.
    ErdQdi F, Ito M, Hartshorne DJ: Myosin light chain phosphatase. In: M. Bárány (eds). Biochemistry of Smooth Muscle. Academic Press, New York, 1996, pp 131-142Google Scholar
  37. 37.
    Johnson DF, Moorhead G, Caudwell FB, Cohen P, Chen YH, Chen MX, Cohen PT: Identification of protein-phosphatase-1-binding domains on the glycogen and myofibrillar targetting subunits. Eur J Biochem 239: 317-325, 1996CrossRefPubMedGoogle Scholar
  38. 38.
    Tóth A, Kiss E, Herberg FW, Gergely P, Hartshorne DJ, Erdődi F: Study of the subunit interactions in myosin phosphatase by surface plasmon resonance. Eur J Biochem 267: 1687-1697, 2000CrossRefPubMedGoogle Scholar
  39. 39.
    Langsetmo K, Stafford WF III, Mabuchi K, Tao T: Recombinant small subunit of smooth muscle myosin light chain phosphatase. Molecular properties and interactions with the targeting subunit. J Biol Chem 276: 34318-34322, 2001CrossRefPubMedGoogle Scholar
  40. 40.
    Trinkle-Mulcahy L, Ichikawa K, Hartshorne DJ, Siegman MJ, Butler TM: Thiophosphorylation of the 130-kDa subunit is associated with a decreased activity of myosin light chain phosphatase in α-toxin-permeabilized smooth muscle. J Biol Chem 270: 18191-18194, 1995CrossRefPubMedGoogle Scholar
  41. 41.
    Ichikawa K, Ito M, Hartshorne DJ: Phosphorylation of the large subunit of myosin phosphatase and inhibition of phosphatase activity. J Biol Chem 271: 4733-4740, 1996CrossRefPubMedGoogle Scholar
  42. 42.
    Kaibuchi K, Kuroda S, Amano M: Regulation of the cytoskeleton and cell adhesion by the Rho family GTPases in mammalian cells. Annu Rev Biochem 68: 459-486, 1999CrossRefPubMedGoogle Scholar
  43. 43.
    Feng J, Ito M, Ichikawa K, Isaka N, Nishikawa M, Hartshorne DJ, Nakano T: Inhibitory phosphorylation site for Rho-associated kinase on smooth muscle myosin phosphatase. J Biol Chem 274: 37385-37390, 1999CrossRefPubMedGoogle Scholar
  44. 44.
    MacDonald JA, Borman MA, Murányi A, Somlyo AV, Hartshorne DJ, Haystead TA: Identification of the endogenous smooth muscle myosin phosphatase-associated kinase. Proc Natl Acad Sci USA 98: 2419-2424, 2001CrossRefPubMedGoogle Scholar
  45. 45.
    Borman MA, MacDonald JA, Murányi A, Hartshorne DJ, Haystead TA: Smooth muscle myosin phosphatase-associated kinase induces Ca2+ sensitization via myosin phosphatase inhibition. J Biol Chem 277: 23441-23446, 2002CrossRefPubMedGoogle Scholar
  46. 46.
    Murányi A, MacDonald JA, Deng JT, Wilson DP, Haystead TA, Walsh MP, Erdődi F, Kiss E, Wu Y, Hartshorne DJ: Phosphorylation of the myosin phosphatase target subunit by integrin-linked kinase. Biochem J 366: 211-216, 2002PubMedGoogle Scholar
  47. 47.
    Kiss E, Murányi A, Csortos C, Gergely P, Ito M, Hartshorne DJ, Erdődi F: Integrin-linked kinase phosphorylates the myosin phosphatase target subunit at the inhibitory site in platelet cytoskeleton. Biochem J 365: 79-87, 2002CrossRefPubMedGoogle Scholar
  48. 48.
    Amano M, Ito M, Kimura K, Fukata Y, Chihara K, Nakano T, Matsuura Y, Kaibuchi K: Phosphorylation and activation of myosin by Rho-associated kinase (Rho-kinase). J Biol Chem 271: 20246-20249, 1996CrossRefPubMedGoogle Scholar
  49. 49.
    Kureishi Y, Kobayashi S, Amano M, Kimura K, Kanaide H, Nakano T, Kaibuchi K, Ito M: Rho-associated kinase directly induces smooth muscle contraction through myosin light chain phosphorylation. J Biol Chem 272: 12257-12260, 1997CrossRefPubMedGoogle Scholar
  50. 50.
    Deng JT, Van Lierop JE, Sutherland C, Walsh MP: Ca2+-independent smooth muscle contraction. A novel function for integrin-linked kinase. J Biol Chem 276: 16365-16373, 2001CrossRefPubMedGoogle Scholar
  51. 51.
    Murata-Hori M, Suizu F, Iwasaki T, Kikuchi A, Hosoya H: ZIP kinase identified as a novel myosin regulatory light chain kinase in HeLa cells. FEBS Lett 451: 81-84, 1999CrossRefPubMedGoogle Scholar
  52. 52.
    Niiro N, Ikebe M: Zipper-interacting protein kinase induces Ca2+-free smooth muscle contraction via myosin light chain phosphorylation. J Biol Chem 276: 29567-29574, 2001CrossRefPubMedGoogle Scholar
  53. 53.
    Murányi A, Zhang R, Liu F, Hirano K, Ito M, Epstein HF, Hartshorne DJ: Myotonic dystrophy protein kinase phosphorylates the myosin phosphatase targeting subunit and inhibits myosin phosphatase activity. FEBS Lett 493: 80-84, 2001CrossRefPubMedGoogle Scholar
  54. 54.
    Takizawa N, Koga Y, Ikebe M: Phosphorylation of CPI17 and myosin binding subunit of type 1 protein phosphatase by p21-activated kinase. Biochem Biophys Res Commun 297: 773-778, 2002CrossRefPubMedGoogle Scholar
  55. 55.
    Broustas CG, Grammatikakis N, Eto M, Dent P, Brautigan DL, Kasid U: Phosphorylation of the myosin-binding subunit of myosin phosphatase by Raf-1 and inhibition of phosphatase activity. J Biol Chem 277: 3053-3059, 2002CrossRefPubMedGoogle Scholar
  56. 56.
    Jin S, Shimizu M, Balasubramanyam A, Epstein HF: Myotonic dystrophy protein kinase (DMPK) induces actin cytoskeletal reorganization and apoptotic-like blebbing in lens cells. Cell Motil Cytoskeleton 45: 133-148, 2000CrossRefPubMedGoogle Scholar
  57. 57.
    Watanabe Y, Ito M, Kataoka Y, Wada H, Koyama M, Feng J, Shiku H, Nishikawa M: Protein kinase C-catalyzed phosphorylation of an inhibitory phosphoprotein of myosin phosphatase is involved in human platelet secretion. Blood 97: 3798-3805, 2001CrossRefPubMedGoogle Scholar
  58. 58.
    Sandu OA, Ito M, Begum N: Selected contribution: Insulin utilizes NO/cGMP pathway to activate myosin phosphatase via Rho inhibition in vascular smooth muscle. J Appl Physiol 91: 1475-1482, 2001PubMedGoogle Scholar
  59. 59.
    Seko T, Ito M, Kureishi Y, Okamoto R, Moriki N, Onishi K, Isaka N, Hartshorne DJ, Nakano T: Activation of RhoA and inhibition of myosin phosphatase as important components in hypertension in vascular smooth muscle. Circ Res 92: 411-418, 2003CrossRefPubMedGoogle Scholar
  60. 60.
    Kitazawa T, Eto M, Woodsome TP, Khalequzzaman M: Phosphorylation of the myosin phosphatase targeting subunit and CPI-17 during Ca2+ sensitization in rabbit smooth muscle. J Physiol 546: 879-889, 2003CrossRefPubMedGoogle Scholar
  61. 61.
    Niiro N, Koga Y, Ikebe M: Agonist-induced changes in the phosphorylation of the myosin-binding subunit of myosin light chain phosphatase and CPI17, two regulatory factors of myosin light chain phosphatase, in smooth muscle. Biochem J 369: 117-128, 2003CrossRefPubMedGoogle Scholar
  62. 62.
    Ito K, Shimomura E, Iwanaga T, Shiraishi M, Shindo K, Nakamura J, Nagumo H, Seto M, Sasaki Y, Takuwa Y: Essential role of rho kinase in the Ca2+ sensitization of prostaglandin F2α-induced contraction of rabbit aortae. J Physiol 546: 823-836, 2003CrossRefPubMedGoogle Scholar
  63. 63.
    Gong MC, Fuglsang A, Alessi D, Kobayashi S, Cohen P, Somlyo AV, Somlyo AP: Arachidonic acid inhibits myosin light chain phosphatase and sensitizes smooth muscle to calcium. J Biol Chem 267: 21492-21498, 1992PubMedGoogle Scholar
  64. 64.
    Fu X, Gong MC, Jia T, Somlyo AV, Somlyo AP: The effects of the Rhokinase inhibitor Y-27632 on arachidonic acid-, GTPγS-, and phorbol ester-induced Ca2+-sensitization of smooth muscle. FEBS Lett 440: 183-187, 1998CrossRefPubMedGoogle Scholar
  65. 65.
    Araki S, Ito M, Kureishi Y, Feng J, Machida H, Isaka N, Amano M, Kaibuchi K, Hartshorne DJ, Nakano: Arachidonic acid-induced Ca2+ sensitization of smooth muscle contraction through activation of Rhokinase. Pflügers Arch 441: 596-603, 2001CrossRefGoogle Scholar
  66. 66.
    Feng J, Ito M, Kureishi Y, Ichikawa K, Amano M, Isaka N, Okawa K, Iwamatsu A, Kaibuchi K, Hartshorne DJ, Nakano T: Rho-associated kinase of chicken gizzard smooth muscle. Rho-associated kinase of chicken gizzard smooth muscle. J Biol Chem 274: 3744-3752, 1999CrossRefPubMedGoogle Scholar
  67. 67.
    Shin HM, Je HD, Gallant C, Tao TC, Hartshorne DJ, Ito M, Morgan KG: Differential association and localization of myosin phosphatase subunits during agonist-induced signal transduction in smooth muscle. Circ Res 90: 546-553, 2002CrossRefPubMedGoogle Scholar
  68. 68.
    Eto M, Ohmori T, Suzuki M, Furuya K, Morita F: A novel protein phosphatase-1 inhibitory protein potentiated by protein kinase C. Isolation from porcine aorta media and characterization. J Biochem (Tokyo) 118: 1104-1107, 1995Google Scholar
  69. 69.
    Eto M, Senba S, Morita F, Yazawa M: Molecular cloning of a novel phosphorylation-dependent inhibitory protein of protein phosphatase-1 (CPI17) in smooth muscle: Its specific. FEBS Lett 410: 356-360, 1997CrossRefPubMedGoogle Scholar
  70. 70.
    Yamawaki K, Ito M, Machida H, Moriki N, Okamoto R, Isaka N, Shimpo H, Kohda A, Okumura K, Hartshorne DJ, Nakano T: Identification of human CPI-17, an inhibitory phosphoprotein for myosin phosphatase. Biochem Biophys Res Commun 285: 1040-1045, 2001CrossRefPubMedGoogle Scholar
  71. 71.
    Eto M, Kitazawa T, Yazawa M, Mukai H, Ono Y, Brautigan DL: Histamine-induced vasoconstriction involves phosphorylation of a specific inhibitor protein for myosin phosphatase by protein kinase C α and δ isoforms. J Biol Chem 276: 29072-29078, 2001CrossRefPubMedGoogle Scholar
  72. 72.
    Hayashi Y, Senba S, Yazawa M, Brautigan DL, Eto M: Defining the structural determinants and a potential mechanism for inhibition of myosin phosphatase by the protein kinase C-potentiated inhibitor protein of 17 kDa. J Biol Chem 276: 39858-39863, 2001CrossRefPubMedGoogle Scholar
  73. 73.
    Li L, Eto M, Lee MR, Morita F, Yazawa M, Kitazawa T: Possible involvement of the novel CPI-17 protein in protein kinase C signal transduction of rabbit arterial smooth muscle. J Physiol 508: 871-881, 1998CrossRefPubMedGoogle Scholar
  74. 74.
    Kitazawa T, Takizawa N, Ikebe M, Eto M: Reconstitution of protein kinase C-induced contractile Ca2+ sensitization in triton X-100-de-membranated rabbit arterial smooth muscle. J Physiol 520: 139-152, 1999CrossRefPubMedGoogle Scholar
  75. 75.
    Koyama M, Ito M, Feng J, Seko T, Shiraki K, Takase K, Hartshorne DJ, Nakano T: Phosphorylation of CPI-17, an inhibitory phosphoprotein of smooth muscle myosin phosphatase, by Rho-kinase. FEBS Lett 475: 197-200, 2000CrossRefPubMedGoogle Scholar
  76. 76.
    Hamaguchi T, Ito M, Feng J, Seko T, Koyama M, Machida H, Takase K, Amano M, Kaibuchi K, Hartshorne DJ, Nakano T: Phosphorylation of CPI-17, an inhibitor of myosin phosphatase, by protein kinase N. Biochem Biophys Res Commun 274: 825-830, 2000CrossRefPubMedGoogle Scholar
  77. 77.
    MacDonald JA, Eto M, Borman MA, Brautigan DL, Haystead TA: Dual Ser and Thr phosphorylation of CPI-17, an inhibitor of myosin phosphatase, by MYPT-associated kinase. FEBS Lett 493: 91-94, 2001CrossRefPubMedGoogle Scholar
  78. 78.
    Deng JT, Sutherland C, Brautigan DL, Eto M, Walsh MP: Phosphorylation of the myosin phosphatase inhibitors, CPI-17 and PHI-1, by integrin-linked kinase. Biochem J 367: 517-524, 2002CrossRefPubMedGoogle Scholar
  79. 79.
    Dubois T, Howell S, Zemlickova E, Learmonth M, Cronshaw A, Aitken A: Novel in vitro and in vivo phosphorylation sites on protein phosphatase 1 inhibitor CPI-17. Biochem Biophys Res Commun 302: 186-192, 2003CrossRefPubMedGoogle Scholar
  80. 80.
    Kitazawa T, Eto M, Woodsome TP, Brautigan DL: Agonists trigger G protein-mediated activation of the CPI-17 inhibitor phosphoprotein of myosin light chain phosphatase to enhance vascular smooth muscle contractility. J Biol Chem 275: 9897-9900, 2000CrossRefPubMedGoogle Scholar
  81. 81.
    Etter EF, Eto M, Wardle RL, Brautigan DL, Murphy RA: Activation of myosin light chain phosphatase in intact arterial smooth muscle during nitric oxide-induced relaxation. J Biol Chem 276: 34681-34685, 2001CrossRefPubMedGoogle Scholar
  82. 82.
    Takizawa N, Niiro N, Ikebe M: Dephosphorylation of the two regulatory components of myosin phosphatase, MBS and CPI17. FEBS Lett 515: 127-132, 2002CrossRefPubMedGoogle Scholar
  83. 83.
    Woodsome TP, Eto M, Everett A, Brautigan DL, Kitazawa T: Expression of CPI-17 and myosin phosphatase correlates with Ca2+ sensitivity of protein kinase C-induced contraction in rabbit smooth muscle. J Physiol 535: 553-564, 2001CrossRefPubMedGoogle Scholar
  84. 84.
    Eto M, Bock R, Brautigan DL, Linden DJ: Cerebellar long-term synaptic depression requires PKC-mediated activation of CPI-17, a myosin/moesin phosphatase inhibitor. Neuron 36: 1145-1158, 2002CrossRefPubMedGoogle Scholar
  85. 85.
    Wu X, Haystead TA, Nakamoto RK, Somlyo AV, Somlyo AP: Acceleration of myosin light chain dephosphorylation and relaxation of smooth muscle by telokin. Synergism with cyclic nucleotide-activated kinase. J Biol Chem 273: 11362-11369, 1998CrossRefPubMedGoogle Scholar
  86. 86.
    Nakamura M, Ichikawa K, Ito M, Yamamori B, Okinaka T, Isaka N, Yoshida Y, Fujita S, Nakano T: Effects of the phosphorylation of myosin phosphatase by cyclic GMP-dependent protein kinase Cell Signal 11: 671-676, 1999CrossRefPubMedGoogle Scholar
  87. 87.
    Dong JM, Leung T, Manser E, Lim L: cAMP-induced morphological changes are counteracted by the activated RhoA small GTPase and the Rho kinase ROKα. J Biol Chem 273: 22554-22562, 1998CrossRefPubMedGoogle Scholar
  88. 88.
    Sauzeau V, Le Jeune H, Cario-Toumaniantz C, Smolenski A, Lohmann SM, Bertoglio J, Chardin P, Pacaud P, Loirand G: Cyclic GMP-dependent protein kinase signaling pathway inhibits RhoA-induced Ca2+ sensitization of contraction in vascular smooth muscle. J Biol Chem 275: 21722-21729, 2000CrossRefPubMedGoogle Scholar
  89. 89.
    Sawada N, Itoh H, Yamashita J, Doi K, Inoue M, Masatsugu K, Fukunaga Y, Sakaguchi S, Sone M, Yamahara K, Yurugi T, Nakao K: cGMP-dependent protein kinase phosphorylates and inactivates RhoA. Biochem Biophys Res Commun 280: 798-805, 2001CrossRefPubMedGoogle Scholar
  90. 90.
    Ellerbroek SM, Wennerberg K, Burridge K: Serine phosphorylation negatively regulates RhoA in vivo. J Biol Chem 278: 19023-19031, 2003CrossRefPubMedGoogle Scholar
  91. 91.
    Seasholtz TM, Majumdar M, Brown JH: Rho as a mediator of G protein-coupled receptor signaling. Mol Pharmacol 55: 949-956, 1999PubMedGoogle Scholar
  92. 92.
    Manganello JM, Huang JS, Kozasa T, Voyno-Yasenetskaya TA, Le Breton GC: Protein kinase A-mediated phosphorylation of the Gα13 switch I region alters the Gαβγ13-G protein-coupled receptor complex and inhibits Rho activation. J Biol Chem 278: 124-130, 2003CrossRefPubMedGoogle Scholar
  93. 93.
    Ito M, Dabrowska R, Guerriero V Jr, Hartshorne DJ: Identification in turkey gizzard of an acidic protein related to the C-terminal portion of smooth muscle myosin light chain kinase. J Biol Chem 264: 13971-13974, 1989PubMedGoogle Scholar
  94. 94.
    Totsukawa G, Yamakita Y, Yamashiro S, Hosoya H, Hartshorne DJ, Matsumura F: Activation of myosin phosphatase targeting subunit by mitosis-specific phosphorylation. J Cell Biol 144: 735-744, 1999CrossRefPubMedGoogle Scholar
  95. 95.
    Feng J, Ito M, Nishikawa M, Okinaka T, Isaka N, Hartshorne DJ, Nakano T: Dephosphorylation of distinct sites on the 20 kDa myosin light chain by smooth muscle myosin phosphatase. FEBS Lett 448: 101-104, 1999CrossRefPubMedGoogle Scholar
  96. 96.
    Fukata Y, Kimura K, Oshiro N, Saya H, Matsuura Y, Kaibuchi K: Association of the myosin-binding subunit of myosin phosphatase and moesin: Dual regulation of moesin phosphorylation by Rho-associated kinase and myosin phosphatase. J Cell Biol 141: 409-418, 1998CrossRefPubMedGoogle Scholar
  97. 97.
    Kimura K, Fukata Y, Matsuoka Y, Bennett V, Matsuura Y, Okawa K, Iwamatsu A, Kaibuchi K: Regulation of the association of adducin with actin filaments by Rho-associated kinase (Rho-kinase) and myosin phosphatase. J Biol Chem 273: 5542-5548, 1998CrossRefPubMedGoogle Scholar
  98. 98.
    Mizuno T, Tsutsui K, Nishida Y: Drosophila myosin phosphatase and its role in dorsal closure. Development 129: 1215-1223, 2002PubMedGoogle Scholar
  99. 99.
    Tan C, Stronach B, Perrimon N: Roles of myosin phosphatase during Drosophila development. Development 130: 671-681, 2003CrossRefPubMedGoogle Scholar
  100. 100.
    Wissmann A, Ingles J, McGhee JD, Mains PE: Caenorhabditis elegans LET-502 is related to Rho-binding kinases and human myotonic dystrophy kinase and interacts genetically with a homolog of the regulatory subunit of smooth muscle myosin phosphatase to affect cell shape. Genes Dev 11: 409-422, 1997PubMedGoogle Scholar
  101. 101.
    Wissmann A, Ingles J, Mains PE: The Caenorhabditis elegans mel-11 myosin phosphatase regulatory subunit affects tissue contraction in the somatic gonad and the embryonic epidermis and genetically interacts with the Rac signaling pathway. Dev Biol 209: 111-127, 1999CrossRefPubMedGoogle Scholar
  102. 102.
    Uehata M, Ishizaki T, Satoh H, Ono T, Kawahara T, Morishita T, Tamakawa H, Yamagami K, Inui J, Maekawa M, Narumiya S: Calcium sensitization of smooth muscle mediated by a Rho-associated protein kinase in hypertension. Nature 389: 990-994, 1997CrossRefPubMedGoogle Scholar
  103. 103.
    Nagumo H, Sasaki Y, Ono Y, Okamoto H, Seto M, Takuwa Y: Rho kinase inhibitor HA-1077 prevents Rho-mediated myosin phosphatase inhibition in smooth muscle cells. Am J Physiol Cell Physiol 278: C57-C65, 2000PubMedGoogle Scholar
  104. 104.
    Seasholtz TM, Zhang T, Morissette MR, Howes AL, Yang AH, Brown JH: Increased expression and activity of RhoA are associated with increased DNA synthesis and reduced p27Kip1 expression in the vasculature of hypertensive rats. Circ Res 89: 488-495, 2001PubMedGoogle Scholar
  105. 105.
    Kandabashi T, Shimokawa H, Miyata K, Kunihiro I, Kawano Y, Fukata Y, Higo T, Egashira K, Takahashi S, Kaibuchi K, Takeshita A: Inhibition of myosin phosphatase by upregulated rho-kinase plays a key role for coronary artery spasm in a porcine model with interleukin-1b. Circulation 101: 1319-1323, 2000PubMedGoogle Scholar
  106. 106.
    Masumoto A, Mohri M, Shimokawa H, Urakami L, Usui M, Takeshita A: Suppression of coronary artery spasm by the Rho-kinase inhibitor fasudil in patients with vasospastic angina. Circulation 105: 1545-1547, 2002CrossRefPubMedGoogle Scholar
  107. 107.
    Sato M, Tani E, Fujikawa H, Kaibuchi K: Involvement of Rho-kinase-mediated phosphorylation of myosin light chain in enhancement of cerebral vasospasm. Circ Res 87: 195-200, 2000PubMedGoogle Scholar
  108. 108.
    Sawada N, Itoh H, Ueyama K, Yamashita J, Doi K, Chun TH, Inoue M, Masatsugu K, Saito T, Fukunaga Y, Sakaguchi S, Arai H, Ohno N, Komeda M, Nakao K: Inhibition of rho-associated kinase results in suppression of neointimal formation of balloon-injured arteries. Circulation 101: 2030-2033, 2000PubMedGoogle Scholar
  109. 109.
    Mukai Y, Shimokawa H, Matoba T, Kandabashi T, Satoh S, Hiroki J, Kaibuchi K, Takeshita A: Involvement of Rho-kinase in hypertensive vascular disease: A novel therapeutic target in hypertension. FASEB J 15: 1062-1064, 2001PubMedGoogle Scholar
  110. 110.
    Itoh K, Yoshioka K, Akedo H, Uehata M, Ishizaki T, Narumiya S: An essential part for Rho-associated kinase in the transcellular invasion of tumor cells. Nat Med 5: 221-225, 1999CrossRefPubMedGoogle Scholar
  111. 111.
    Wettschureck N, Offermanns S: Rho/Rho-kinase mediated signaling in physiology and pathophysiology. J Mol Med 80: 629-638, 2002CrossRefPubMedGoogle Scholar

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Masaaki Ito
    • 1
  • Takeshi Nakano
    • 1
  • Ferenc Erdődi
    • 2
  • David J. Hartshorne
    • 3
  1. 1.First Department of Internal MedicineMie University School of MedicineTsu, MieJapan
  2. 2.Department of Medical Chemistry, Medical and Health Science CenterUniversity of DebrecenDebrecenHungary
  3. 3.Muscle Biology GroupUniversity of ArizonaTucsonUSA

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