title: The length-tension curve in muscle depends on lattice spacing.
abstract: Classic interpretations of the striated muscle length-tension curve focus on how force varies with overlap of thin (actin) and thick (myosin) filaments. New models of sarcomere geometry and experiments with skinned synchronous insect flight muscle suggest that changes in the radial distance between the actin and myosin filaments, the filament lattice spacing, are responsible for between 20% and 50% of the change in force seen between sarcomere lengths of 1.4 and 3.4 µm. Thus, lattice spacing is a significant force regulator, increasing the slope of muscle's force-length dependence.
authors.affiliation: Department of Physiology and Biophysics, University of Washington, , Seattle, WA, USA. cdave@uw.edu
authors.forename: C David
authors.initials: CD
authors.lastname: Williams
authors.forename: Mary K
authors.initials: MK
authors.lastname: Salcedo
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Irving
authors.forename: Michael
authors.initials: M
authors.lastname: Regnier
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Daniel
mesh_terms: D000818:Animals; D005426:Flight, Animal / Q000502:physiology; D007313:Insecta / Q000033:anatomy & histology / Q000502:physiology / Q000648:ultrastructure; D009129:Muscle Tonus; D054792:Muscle, Striated / Q000033:anatomy & histology / Q000502:physiology* / Q000648:ultrastructure; D012518:Sarcomeres / Q000648:ultrastructure; D014961:X-Ray Diffraction
keywords: X-ray diffraction; lattice spacing; length–tension curve; muscle contraction; spatially explicit