Abstract
Patterns of intrinsic birefringence were revealed in formalin-fixed, glycerinated myofibrils from rabbit striated muscle, by perfusing them with solvents of refractive index near to that of protein, about 1.570. The patterns differ substantially from those obtained in physiological salt solutions, due to the elimination of edge- and form birefringence. Analysis of myofibrils at various stages of shortening has produced results fully consistent with the sliding filament theory of contraction. On a weight basis, the intrinsic birefringence of thick-filament protein is about 2.4 times that of thin-filament protein. Nonadditivity of thick- and thin-filament birefringence in the overlap regions of A bands may indicate an alteration of macromolecular structure due to interaction between the two types of filaments.
Full Text
The Full Text of this article is available as a PDF (692.0 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- ALLEN R. D., NAKAJIMA H. TWO-EXPOSURE, FILM DENSITOMETRIC METHOD MEASURING PHASE RETARDATIONS DUE TO WEAK BIREFRINGENCE IN FIBRILLAR OR MEMBRANOUS CELL CONSTITUENTS. Exp Cell Res. 1965 Jan;37:230–249. doi: 10.1016/0014-4827(65)90172-2. [DOI] [PubMed] [Google Scholar]
- ARONSON J. OVERLAP OF THE BIREFRINGENT COMPONENT OF ADJACENT A REGIONS DURING THE INDUCED SHORTENING OF FIBRILS TEASED FROM DROSOPHILA MUSCLE. J Cell Biol. 1963 Oct;19:107–114. doi: 10.1083/jcb.19.1.107. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Elliott G. F. Variations of the contractile apparatus in smooth and striated muscles. X-ray diffraction studies at rest and in contraction. J Gen Physiol. 1967 Jul;50(6 Suppl):171–184. doi: 10.1085/jgp.50.6.171. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HUXLEY A. F. Muscle structure and theories of contraction. Prog Biophys Biophys Chem. 1957;7:255–318. [PubMed] [Google Scholar]
- HUXLEY H. E. Electron microscope studies of the organisation of the filaments in striated muscle. Biochim Biophys Acta. 1953 Nov;12(3):387–394. doi: 10.1016/0006-3002(53)90156-5. [DOI] [PubMed] [Google Scholar]
- HUXLEY H. E., HANSON J. Quantitative studies on the structure of cross-striated myofibrils. I. Investigations by interference microscopy. Biochim Biophys Acta. 1957 Feb;23(2):229–249. doi: 10.1016/0006-3002(57)90325-6. [DOI] [PubMed] [Google Scholar]
- Hoyle G., McAlear J. H., Selverston A. Mechanism of supercontraction in a striated muscle. J Cell Biol. 1965 Aug;26(2):621–640. doi: 10.1083/jcb.26.2.621. [DOI] [PMC free article] [PubMed] [Google Scholar]
- INOUE S., HYDE W. L. Studies on depolarization of light at microscope lens surfaces. II. The simultaneous realization of high resolution and high sensitivity with the polarizing microscope. J Biophys Biochem Cytol. 1957 Nov 25;3(6):831–838. doi: 10.1083/jcb.3.6.831. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kane R. E., Forer A. The mitotic apparatus. Structural changes after isolation. J Cell Biol. 1965 Jun;25(3 Suppl):31–39. doi: 10.1083/jcb.25.3.31. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PAGE S. G., HUXLEY H. E. FILAMENT LENGTHS IN STRIATED MUSCLE. J Cell Biol. 1963 Nov;19:369–390. doi: 10.1083/jcb.19.2.369. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reedy M. K., Holmes K. C., Tregear R. T. Induced changes in orientation of the cross-bridges of glycerinated insect flight muscle. Nature. 1965 Sep 18;207(5003):1276–1280. doi: 10.1038/2071276a0. [DOI] [PubMed] [Google Scholar]
- SZENT-GYORGYI A. G. A new method for the preparation of actin. J Biol Chem. 1951 Sep;192(1):361–369. [PubMed] [Google Scholar]
- Szent-Györgyi A. G., Prior G. Exchange of adenosine diphosphate bound to actin in superprecipitated actomyosin and contracted myofibrils. J Mol Biol. 1966 Feb;15(2):515–538. doi: 10.1016/s0022-2836(66)80125-0. [DOI] [PubMed] [Google Scholar]