Straightening Out the Elasticity of Myosin Cross-Bridges.
Biophys J
; 118(5): 994-1002, 2020 03 10.
Article
en En
| MEDLINE
| ID: mdl-31968230
ABSTRACT
In a contracting muscle, myosin cross-bridges extending from thick filaments pull the interdigitating thin (actin-containing) filaments during cyclical ATP-driven interactions toward the center of the sarcomere, the structural unit of striated muscle. Cross-bridge attachments in the sarcomere have been reported to exhibit a similar stiffness under both positive and negative forces. However, in vitro measurements on filaments with a sparse complement of heads detected a decrease of the cross-bridge stiffness at negative forces attributed to the buckling of the subfragment 2 tail portion. Here, we review some old and new data that confirm that cross-bridge stiffness is nearly linear in the muscle filament lattice. The implications of high myosin stiffness at positive and negative strains are considered in muscle fibers and in nonmuscle intracellular cargo transport.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Miosinas
/
Contracción Muscular
Idioma:
En
Revista:
Biophys J
Año:
2020
Tipo del documento:
Article
País de afiliación:
Italia