Calcium-Induced Structural Changes in Synthetic Myosin Filaments of Vertebrate Striated Muscles

Podlubnaya, Z. A.; Kakol, I; Moczarska, A; Stȩpkowski, Dariusz; Udaltsov, S. N.

doi:10.1006/jsbi.1999.4129

Cited by 19 publications

(11 citation statements)

References 61 publications

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“…The main problem in arresting the Ca 2+ -induced structural transformation in vertebrate striated native and synthetic myosin filaments is the difficulty to preserve the ordered ("relaxing") state (Ménétret et al, 1990, Podlubnaya et al, 1999a. Although, accord-ing to our EM-observations, the ordered structure with 14.5 nm-periodicity predominated in the majority of the synthetic filaments of fast skeletal and cardiac muscle myosins in the absence of Ca 2+ , however some filaments or their regions remained partially disordered.…”

supporting

confidence: 71%

“…47 Structural transitions in myosin filaments 1011 preparations do not show such a repeat in synthetic filaments, and the procedure of purification on the DEAE-Sephacel column was in both cases the same, we assume that the 43 nm repeat might be a structural property of slow skeletal muscle myosin filaments. In the presence of 0.1 mM excess of Ca 2+ over EGTA the structure of slow skeletal muscle myosin filaments is indistinguishable from that of fast skeletal, cardiac (Podlubnaya et al, 1999a) and smooth (Podlubnaya et al, 1999b) muscle myosin filaments ( Fig. 3c and d).…”

Section: Resultsmentioning

confidence: 82%

“…In our previous works (Podlubnaya et al, 1999a;1999b) we have observed Ca 2+ induced structural transitions in synthetic cardiac and fast skeletal muscle myosin filaments in the absence of ATP. When Podlubnaya et al (1999b) applied the conditions of Frado & Craig (1989) (the presence of ATP, -/+ Ca 2+ ) to synthetic filaments of unphosphorylated smooth muscle myosin, significantly more pronounced striations (14.5 nm repeat) were observed in filaments under relaxing conditions (2 mM ATP, the absence of Ca 2+ ).…”

Section: Resultsmentioning

confidence: 86%

“…The saturation of the low affinity sites with Mg 2+ can lead to association of crossbridges with the filament backbone (Reisler et al, 1983). By the use of electron microscopy such an association was observed for synthetic filaments of fast skeletal, cardiac (Podlubnaya et al, 1999a) and smooth (Podlubnaya et al, 1999b) muscle myosins in the absence of Ca 2+ but in the presence of millimolar concentrations of free Mg 2+ . In the same solution in the presence of free 0.1 mM Ca 2+ the compact ordered filament structure with 14.5 nm axial repeat, characteristic for myosin heads (and subfragments 2, S2) associated with the filament backbone, was transformed into the disordered "spread" structure with randomly arranged heads and S2s.…”

mentioning

confidence: 96%

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Order-disorder structural transitions in synthetic filaments of fast and slow skeletal muscle myosins under relaxing and activating conditions.

Podlubnaya

Malyshev²,

Nieznañski³

et al. 2000

Acta Biochim Pol

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Key words: fast and slow skeletal muscle myosin, myosin filaments, Ca 2+ -induced structural transitions, method of slow skeletal muscle myosin preparation. In the previous study (Podlubnaya et al., 1999, J. Struc. Biol. 127, 1-15) Ca 2+ -induced reversible structural transitions in synthetic filaments of pure fast skeletal and cardiac muscle myosins were observed under rigor conditions (-Ca 2+ /+ Ca 2+ ). In the present work these studies have been extended to new more order-producing conditions (presence of ATP in the absence of Ca 2+ ) aimed at arresting the relaxed structure in synthetic filaments of both fast and slow skeletal muscle myosin. Filaments were formed from column-purified myosins (rabbit fast skeletal muscle and rabbit slow skeletal semimebranosus proprius muscle). In the presence of 0.1 mM free Ca 2+ , 3 mM Mg 2+ and 2 mM ATP (activating conditions) these filaments had a spread structure with a random arrangement of myosin heads and subfragments 2 protruding from the filament backbone. Such a structure is indistinguishable from the filament structures observed previously for fast skeletal, cardiac (see reference cited above) and smooth (Podlubnaya et al., 1999, J. Muscle Res. Cell Motil. 20, 547-554) muscle myosins in the presence of 0.1 mM free Ca 2+ . In the absence of Ca 2+ and in the presence of ATP (relaxing conditions) the filaments of both studied myosins revealed a compact ordered structure. The fast skeletal muscle myosin filaments exhibited an ax-Vol. 47 No. 4/2000 1007-1017 QUARTERLY .

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supporting

confidence: 71%

Section: Resultsmentioning

confidence: 82%

Section: Resultsmentioning

confidence: 86%

mentioning

confidence: 96%

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Order-disorder structural transitions in synthetic filaments of fast and slow skeletal muscle myosins under relaxing and activating conditions.

Podlubnaya

Malyshev²,

Nieznañski³

et al. 2000

Acta Biochim Pol

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“…However, there are other effects of H + . Podlubnaya et al (12) have reported that increased pH results in a disordered pattern of myosin head position relative to the thick filament, similar to the changes observed when the regulatory light chains are phosphorylated. This could mean that the mechanism of increased pCa 2+ 50 with alkalosis is similar to the mechanism described above for regulatory light-chain phosphorylation.…”

Section: Figurementioning

confidence: 69%