title: [Effect of phosphorylation of light chain myosin and Ca2+ on the conformation of F-actin during skeletal muscle contraction].
abstract: The dependence of polarized fluorescence of rhodaminylphalloin specifically bound to F-actin and the tension developed by a fiber upon phosphorylation of myosin (18.5 kD) light chains as well as on the concentration of free Ca2+ was observed during the contraction of glycerinated rabbit skeletal muscle fibers. Still greater changes in the polarized fluorescence and higher values of tension were recorded for fibers with phosphorylated light chains at low (0.6 microM) Ca2+ concentrations as well as for those with dephosphorylated light chains at high (10 microM) Ca2+ concentrations. It is concluded that phosphorylation of myosin light chains modulates skeletal muscle contraction. The mechanisms of modulation involve conformational changes in F-actin.
authors.forename: Iu S
authors.initials: IuS
authors.lastname: Borovikov
authors.forename: M
authors.initials: M
authors.lastname: Vrotek
authors.forename: N N
authors.initials: NN
authors.lastname: Lebedeva
authors.forename: I
authors.initials: I
authors.lastname: Konkol'
mesh_terms: D000199:Actins / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D005453:Fluorescence; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects*; D009132:Muscles / Q000378:metabolism*; D015879:Myosin Subfragments; D009218:Myosins / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism*; D010766:Phosphorylation; D011817:Rabbits
chemical_list: D000199:Actins; D015879:Myosin Subfragments; D010446:Peptide Fragments; D009218:Myosins; D002118:Calcium
vernacular_title: Vliianie fosforilirovaniia legkikh tsepeĭ miozina i Ca2+ na konformatsiiu F-aktina pri sokrashchenii skeletnykh myshts.