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. 1969 Jun 1;53(6):781–791. doi: 10.1085/jgp.53.6.781

Parallel Response of Myofibrillar Contraction and Relaxation to Four Different Nucleoside Triphosphates

A Weber 1
PMCID: PMC2202881  PMID: 4239137

Abstract

The Mg chelates of ITP, GTP, and UTP in addition to that of ATP were shown to be capable of causing complete relaxation of myofibrils as indicated by the complete inhibition of syneresis and the reduction of the NTPase activity to that of isolated myosin. For ITP and GTP the required concentrations were about 100 times higher than those for ATP, whereas UTP was maximally effective also in low concentrations (0.2 mM). For all NTP's the concentrations for relaxation were related to those necessary for contraction so that NTP concentrations which gave 80–90% maximal NTPase activity in the presence of Ca caused complete relaxation in the absence of Ca. Thus, these experiments do not support the view that relaxation is caused by the binding of NTP to a special inhibitory site but are quite compatible with the idea that relaxation depends on the extent to which the hydrolytic site is saturated with NTP. The Ca concentration required for contraction depends on the nature of the NTP base and its concentration; it is lower for ITP than for ATP and decreases with decreasing concentrations of ITP.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. BENDALL J. R. Relaxation of glycerol-treated muscle fibers by ethylenediamine tetraacetate. Arch Biochem Biophys. 1958 Jan;73(1):283–285. doi: 10.1016/0003-9861(58)90267-4. [DOI] [PubMed] [Google Scholar]
  2. CARSTEN M. E., MOMMAERTS W. F. THE ACCUMULATION OF CALCIUM IONS BY SARCOTUBULAR VESICLES. J Gen Physiol. 1964 Nov;48:183–197. doi: 10.1085/jgp.48.2.183. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. ENDO M. THE SUPERPRECIPITATION OF ACTOMYOSIN AND ITS ATPASE ACTIVITY IN LOW CONCENTRATION OF ATP. J Biochem. 1964 Jun;55:614–622. doi: 10.1093/oxfordjournals.jbchem.a127934. [DOI] [PubMed] [Google Scholar]
  4. Ebashi S., Ebashi F., Kodama A. Troponin as the Ca++-receptive protein in the contractile system. J Biochem. 1967 Jul;62(1):137–138. doi: 10.1093/oxfordjournals.jbchem.a128628. [DOI] [PubMed] [Google Scholar]
  5. Ebashi S., Endo M. Calcium ion and muscle contraction. Prog Biophys Mol Biol. 1968;18:123–183. doi: 10.1016/0079-6107(68)90023-0. [DOI] [PubMed] [Google Scholar]
  6. Ebashi S., Kodama A., Ebashi F. Troponin. I. Preparation and physiological function. J Biochem. 1968 Oct;64(4):465–477. doi: 10.1093/oxfordjournals.jbchem.a128918. [DOI] [PubMed] [Google Scholar]
  7. Eggleton P., Elsden S. R., Gough N. The estimation of creatine and of diacetyl. Biochem J. 1943;37(5):526–529. doi: 10.1042/bj0370526. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Fuchs F., Briggs F. N. The site of calcium binding in relation to the activation of myofibrillar contraction. J Gen Physiol. 1968 May;51(5):655–676. doi: 10.1085/jgp.51.5.655. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. HANSON J., HUXLEY H. E. Quantitative studies on the structure of cross-striated myofibrils. II. Investigations by biochemical techniques. Biochim Biophys Acta. 1957 Feb;23(2):250–260. doi: 10.1016/0006-3002(57)90326-8. [DOI] [PubMed] [Google Scholar]
  10. HASSELBACH W. Die Wechselwirkung verschiedener Nukleosidtriphosphate mit Aktomyosin in Gelzustand. Biochim Biophys Acta. 1956 May;20(2):355–368. doi: 10.1016/0006-3002(56)90297-9. [DOI] [PubMed] [Google Scholar]
  11. HASSELBACH W., MAKINOSE M. [The calcium pump of the "relaxing granules" of muscle and its dependence on ATP-splitting]. Biochem Z. 1961;333:518–528. [PubMed] [Google Scholar]
  12. LEVY H. M., RYAN E. M. EVIDENCE THAT CALCIUM ACTIVATES THE CONTRACTION OF ACTOMYOSIN BY OVERCOMING SUBSTRATE INHIBITION. Nature. 1965 Feb 13;205:703–705. doi: 10.1038/205703b0. [DOI] [PubMed] [Google Scholar]
  13. Levy H. M., Ryan E. M. The contractile and control sites of natural actomyosin. J Gen Physiol. 1967 Nov;50(10):2421–2435. doi: 10.1085/jgp.50.10.2421. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. MARTONOSI A., FERETOS R. SARCOPLASMIC RETICULUM. II. CORRELATION BETWEEN ADENOSINE TRIPHOSPHATASE ACTIVITY AND CA++ UPTAKE. J Biol Chem. 1964 Feb;239:659–668. [PubMed] [Google Scholar]
  15. MARTONOSI A. The specificity of the interaction of adenosine triphosphate with G-actin. Biochim Biophys Acta. 1962 Feb 12;57:163–165. doi: 10.1016/0006-3002(62)91098-3. [DOI] [PubMed] [Google Scholar]
  16. Slayter H. S., Lowey S. Substructure of the myosin molecule as visualized by electron microscopy. Proc Natl Acad Sci U S A. 1967 Oct;58(4):1611–1618. doi: 10.1073/pnas.58.4.1611. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. TAUSSKY H. H., SHORR E. A microcolorimetric method for the determination of inorganic phosphorus. J Biol Chem. 1953 Jun;202(2):675–685. [PubMed] [Google Scholar]
  18. WEBER A., HERZ R., REISS I. THE REGULATION OF MYOFIBRILLAR ACTIVITY BY CALCIUM. Proc R Soc Lond B Biol Sci. 1964 Oct 27;160:489–501. doi: 10.1098/rspb.1964.0063. [DOI] [PubMed] [Google Scholar]
  19. WEBER A., WINICUR S. The role of calcium in the superprecipitation of actomyosin. J Biol Chem. 1961 Dec;236:3198–3202. [PubMed] [Google Scholar]

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