Summary
Ca2+-dependent protein kinase (CDPK) has been proposed to mediate inhibition by Ca2+ of cytoplasmic streaming in the green algaChara. We have identified the in vivo substrate(s) of CDPK inChara by using vacuolar perfusion of individual internodal cells with [γ-32P]ATP. Phosphorylation of several polypeptides is enhanced when perfusions are performed at 10−4M free Ca2+ compared to <10−9M free Ca2+. The Ca2+-stimulated phosphorylation of these proteins is inhibited by the presence of a monoclonal antibody to soybean CDPK. One of these proteins is 16 to 18kDa and is recognized by an antibody against gizzard myosin light chains. These results demonstrate that inChara, several polypeptides are phophorylated by CDPK and one of these proteins has been tentatively identified as a myosin light chain. These observations support the hypothesis that Ca2+-regulated phosphorylation of myosin is involved in the regulation of cytoplasmic streaming.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Abbreviations
- CDPK:
-
calcium-dependent protein kinase
- mAb:
-
monoclonal antibody
References
Cheney RE, Mooseker MS (1992) Unconventional myosins. Curr Opin Cell Biol 4: 27–35
Grolig F, Williamson RE, Parke J, Miller C, Anderton BH (1988) Myosin and Ca2+-sensitive streaming in the algaChara: two polypeptides reacting with a monoclonal anti-myosin and their localization in the streaming endoplasm. Eur J Cell Biol 47: 22–31
Harmon AC, Putnam-Evans C, Cormier MJ (1987) A calcium-dependent but calmodulin-independent protein kinase from soybean. Plant Physiol 83: 830–837
Harper JF, Sussman MR, Schaller GE, Putnam-Evans C, Charbonneau H, Harmon AC (1991) A calcium-dependent protein kinase with a regulatory domain similar to calmodulin. Science 252: 951–954
Korn ED, Hammer JA III (1988) Myosins of nonmuscle cells. Annu Rev Biophys Biophys Chem 17: 23–45
Kuznicki J (1986) Phosphorylation of myosin in non-muscle and smooth muscle cells. Possible rules and evolutionary trends. FEBS Lett 204: 169–176
Laemmli UK (1970) Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227: 680–685
Ma YZ, Yen LF (1989) Actin and myosin in pea tendrils. Plant Physiol 89: 586–589
McCurdy DW, Harmon AC (1992) Calcium-dependent protein kinase in the green algaChara. Planta 188 (in press)
McCurdy DW, Williamson RE (1991) Actin and actin-associated proteins. In: Lloyd CW (ed) The cytoskeletal basis of plant growth and form. Academic Press, London
Putnam-Evans C, Harmon AC, Cormier MJ (1990) Purification and characterization of a novel calcium-dependent protein kinase from soybean. Biochemistry 29: 2488–2495
— —, Palevitz BA, Fechheimer M, Cormier MJ (1989) Calciumdependent protein kinase is localized with F-actin in plant cells. Cell Motil Cytoskeleton 12: 12–22
Roberts DM, Harmon AC (1992) Calcium-modulated proteins: targets of intracellular calcium signals in higher plants. Annu Rev Plant Physiol Plant Mol Biol 43: 375–414
Schagger H, von Jagow G (1987) Tricine-sodium dodecyl sulfatepolyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa. Anal Biochem 166: 368–379
Schaller GE, Sussman MR (1988) Phosphorylation of the plasma membrane H+-ATPase of oat roots by calcium-stimulated protein kinase. Planta 173: 509–518
—, Harmon AC, Sussman MR (1992) Characterization of a calciumdependent and lipid-dependent protein kinase associated with the plasma membrane of oat. Biochem 31: 1721–1727
Tominaga Y, Wayne R, Tung HYL, Tazawa M (1987) Phosphorylation-dephosphorylation is involved in Ca2+-controlled cytoplasmic streaming of Characean cells. Protoplasma 136: 161–169
Vahey M, Titus M, Trautwein R, Scordilis S (1982) Tomato actin and myosin: contractile proteins from a higher plant. Cell Motil 2: 131–147
Van Eldick LJ, Wolchok SR (1982) Conditions for reproducible detection of calmodulin and S 100 in immunoblots. Biochem Biophys Res Commun 124: 752–759
Williamson RE (1975) Cytoplasmic streaming inChara: a cell model activated by ATP and inhibited by cytochalasin B. J Cell Sci 17: 655–668
— (1991) Cytoplasmic streaming in Characean algae: mechanism, regulation by Ca2+ and organization. In: Melkonian M (ed) Algal cell motility. Chapman and Hall, London
—, Ashley CC (1982) Free Ca2+ and Cytoplasmic streaming in the algaChara. Nature 296: 647–651
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
McCurdy, D.W., Harmon, A.C. Phosphorylation of a putative myosin light chain inChara by calcium-dependent protein kinase. Protoplasma 171, 85–88 (1992). https://doi.org/10.1007/BF01379284
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01379284