Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Contractile protein interactions in smooth muscle.

J C Rüegg1, G Pfitzer

  • 1Department of Physiology II, University of Heidelberg, FRG.

Blood Vessels
|January 1, 1991
PubMed
Summary

Smooth muscle contraction relies on cross-bridge cycling rate constants. Myosin light chain phosphorylation influences these rates, affecting muscle tone and economy.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The involvement of phosphorylation of myosin phosphatase targeting subunit 1 (MYPT1) and MYPT1 isoform expression in NO/cGMP mediated differential vasoregulation of cerebral arteries compared to systemic arteries.

Acta physiologica (Oxford, England)·2018
Same author

Biomechanical adaptation to hindlimb suspension: it involves not only transcriptional mechanisms but also post-translational modification of the molecular motor, myosin.

Acta physiologica (Oxford, England)·2014
Same author

Muscle sound during macroscale skeletal muscle relaxation: is it linked to processes on the microscale sarcomere level?

Acta physiologica (Oxford, England)·2014
Same author

Deep hypothermia in vivo - why is it so deleterious for the heart?

Acta physiologica (Oxford, England)·2013
Same author

[Myosin phosphorylation as the main way of regulating smooth muscle contractions].

Rossiiskii fiziologicheskii zhurnal imeni I.M. Sechenova·2009
Same author

CAP2, cyclase-associated protein 2, is a dual compartment protein.

Cellular and molecular life sciences : CMLS·2007

Area of Science:

  • Physiology
  • Biochemistry
  • Muscle Biology

Background:

  • Smooth muscle tone and its 'holding economy' are regulated by the kinetics of the cross-bridge cycle.
  • Calcium activation, through calmodulin-dependent myosin light chain phosphorylation, is a key factor influencing cross-bridge cycling rates.

Purpose of the Study:

  • To investigate the role of myosin light chain phosphorylation in regulating the cross-bridge cycle's rate constants.
  • To explore the effects of a calmodulin recognition site peptide mimic (RS 20) on smooth muscle relaxation.
  • To understand the mechanisms behind the 'latch state' and force maintenance in smooth muscle.

Main Methods:

  • Utilized skinned smooth muscle fiber preparations.
  • Employed a peptide mimic (RS 20) of the calmodulin recognition site of myosin light chain kinase to inhibit phosphorylation.
  • Analyzed apparent cross-bridge rate constants ('f' and 'g') governing attachment and detachment.

Main Results:

  • Myosin light chain phosphorylation rate constants appear to determine cross-bridge entry into the force-generating state.
  • The peptide mimic RS 20 inhibited light chain phosphorylation, leading to smooth muscle relaxation.
  • A low apparent cross-bridge detachment rate constant ('g') is associated with high holding economy and the 'latch state'.

Conclusions:

  • Myosin light chain phosphorylation is a critical determinant of smooth muscle cross-bridge kinetics and force generation.
  • The 'latch state' is characterized by a low detachment rate, enabling sustained force with low energy expenditure.
  • Other regulatory proteins like calponin and caldesmon may also modulate cross-bridge attachment in smooth muscle.

Related Experiment Videos