Abstract
Two effects of Mn2+ on skinned fibers from chicken gizzard smooth muscle were observed, dependent on the presence of absence of dithiothreitol (DTT) reducing agent. One involves protein oxidation (in the absence of DTT) with production of a “latch”-like state, and the other involves direct Mn2+ activation of contractile proteins. Cells activated by Mn2+ in the presence of ATP and the absence of Ca2+, Mg2+ and DTT did not relax when transferred to normal relaxing solutions. In contrast, when 5 mM DTT was included in the Mn2+ contracting solution to prevent protein oxidation by Mn2+, the cells still contracted when exposed to Mn2+, but relaxed rapidly when the Mn2+ was removed. In the presence of DTT both the Mn2+ activation and the relaxation following removal of Mn2+ were more rapid than normal Ca2+-activated contractions and relaxations. The skinned fibers activated by Mn2+ in the absence of DTT showed little active shortening unless DTT was added. This rigor-like state is probably due to oxidation of contractile proteins since the cells relaxed when exposed to a relaxing solution containing DTT (50mM) and then contracted again in response to Ca2+ and relaxed normally. The Mn2+ activation was not associated with myosin light chain phosphorylation, in contrast to Ca2+-activated contractions.
Similar content being viewed by others
References
Adelstein RS, Klee CB (1983) Purification and characterization of smooth muscle myosin light chain kinase. J Biol Chem 256:7501–7509
Bagshaw CR (1980) Divalent metal ion binding and subunit interactions in myosins: a critical review. J Muscle Res Cell Motil 1:255–277
Chacko S (1981) Effects of phosphorylation, calcium ion, and tropomyosin on actin-activated adenosine 5′-triphosphate activity of mammalian smooth muscle myosin. Biochemistry 20:702–707
Chacko S, Rosenfeld A (1982) Regulation of actin-activated ATP hydrolysis by arterial myosin. Proc Natl Acad Sci USA 79(1):292–296
Chao S-H, Suzuki Y, Zysk JR, Cheung WY (1984) Activation of calmodulin by various metal cations as a function of ionic radius. Mol Pharmacol 26:75–82
Clark T, Ngai PK, Sutherland C, Groschel-Stewart U, Walsh MP (1986) Vascular smooth muscle caldesmon. J Biol Chem 261(17):8028–8035
Donaldson SKB, Kerrick WGL (1975) Characterization of the effects of Mg2+ on Ca2+-and Sr2+-activated tension generation of skinned skeletal muscle fibers. J Gen Physiol 66:427–444
Hartshorne DJ, Siemankowski TF (1981) Regulation of smooth muscle actomyosin. Annu Rev Physiol 43:519–530
Hellam DC, Podolsky RJ (1969) Force measurements in skinned muscle fibres. J Physiol (Lond) 200:807–819
Hoar PE, Kerrick WGL, Cassidy PS (1979) Chicken gizzard: relation between calcium-activated phosphorylation and contraction. Science 204:503–506
Poar PE, Pato MD, Kerrick WGL (1985) Myosin light chain phosphatase: Effect on the activation and relaxation of gizzard smooth muscle skinned fibers. J Biol Chem 260(15):8760–8764
Hozumi T, Tawada K (1975) Temperature-dependent transitions of the myosin-product intermediate at 10°C in the Mn(II)-ATP hydrolysis. Biochim Biophys Acta 376:1–12
Ikebe M, Hinkins S, Hartshorne DJ (1983) Correlation of enzymatic properties and conformation of muscle myosin. Biochemistry 22:4580–4587
Kamm KE, Stull JT (1985) The function of myosin and myosin light chain kinase phosphorylation in smooth muscle. Annu Rev Pharmacol Toxicol 25:593–620
Kerrick WGL, Bolles LL (1982) Evidence that myosin light chain phosphorylation regulates contraction in the body wall muscles of the sea cucumber. J Cell Physiol 112:307–315
Kerrick WGL, Hoar PE (1985) Regulation of contraction in skinned smooth muscle cells by Ca2+ and protein phosphorylation. In: Merlevede M, DiSalvo J (eds) Advances in protein phosphatases II. Leuven University Press, Leuven, pp 133–152
Kerrick WGL, Hoar PE (1986) Smooth muscle: regulation by calcium and phosphorylation. In: Evered D, Whelan J (eds) Calcium and the cell, Ciba Foundation Symposium 122. Wiley, New York, pp 183–196
Kerrick WGL, Krasner B (1975) Disruption of the sarcolemma of mammalian skeletal muscle fibers by homogenization. J Appl Physiol 39:1052–1055
Lash JA, Sellers JR, Hathaway DR (1986) The effects of caldesmon on smooth muscle heavy actomeromyosin ATPase activity and binding of heavy meromyosin to actin. J Biol Chem 261:16155–16160
Lynch WP, Riseman VM, Bretscher A (1987) Smooth muscle caldesmon is an extended flexible monomeric protein in solution that can readily undergo reversible intra- and intermolecular sulfhydryl cross-linking. A mechanism for caldesmon's F-actin bundling activity. J Biol Chem 262:7429–7437
Marston SB, Smith SJ (1984) Purification and properties of Ca2+ regulated thin filaments and F-actin from sheep aorta smooth muscle. J Muscle Res Cell Motil 5:559–575
Marston SB, Taylor EW (1980) Comparison of the myosin and actomyosin ATPase mechanism of the four types of vertebrate muscles. J Mol Biol 139:573–600
Murphy RA (1980) Mechanics of vascular smooth muscle. In: Bohr DF, Somlyo, AP, Sparks Jr HV (eds) Handbook of physiology. Section 2. The cardiovascular system, vol II. Vascular smooth muscle. American Physiological Society, Bethesa, MD, pp 325–351
Ngai PK, Walsh MP (1987) Purification of smooth-muscle myosin free of calmodulin and myosin light-chain kinase. Susceptibility to oxidation. Biochem J 246:205–211
Saida K, Nonomura Y (1978) Characteristics of Ca2+- and Mg2+-induced tension development in chemically skinned smooth muscle fibers. J Gen Physiol 72:1–14
Seidel JC (1979) Activation by actin of ATPase activity of chemically modified gizzard myosin without phosphorylation. Biochem Biophys Res Commun 89:958–964
Seidel JC, Nath N, Nag S (1986) Ca2+ Dependence of the ATPase activity of phosphorylated smooth muscle myosin: effects of tropomyosin and actin. Biochim Biophys Acta 871:93–100
Smith RM, Martell AE (1975) Critical stability constants, vol 2. Plenum Press, New York, p 283
Wagner J, Rüegg JC (1986) Skinned smooth muscle: calcium-calmodulin activation independent of myosin phosphorylation. Pflügers Arch 407:569–571
Walsh MP, Bridenbaugh RL, Kerrick WGL, Hartshorne DJ (1983) Gizzard Ca2+-independent myosin light chain kinase: evidence in favor of the phosphorylation theory. Fed Proc 42:45–50
Yoshida A, Tawada K (1976) Temperature-dependence of tension development by glycerinated muscle fibers of rabbit psoas in Mn(II)-ATP and Mg-ATP solutions. J Biochem 80:861–865
Author information
Authors and Affiliations
Additional information
A preliminary report of this work was given at the Biophysical Society Meeting, February 1987: Hoar PE, Kerrick WGL (1987) Mn2+ activates skinned smooth muscle cells directly without myosin light chain phosphorylation and by reversible oxidation. Biophys J 51:332a
Rights and permissions
About this article
Cite this article
Hoar, P.E., Kerrick, W.G.L. Mn2+ activates skinned smooth muscle cells in the absence of myosin light chain phosphorylation. Pflugers Arch. 412, 225–230 (1988). https://doi.org/10.1007/BF00582501
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00582501