Phosphorylation of myosin regulatory light chain eliminates force-dependent changes in relaxation rates in skeletal muscle

Biophysical Journal
J R PatelR L Moss

Abstract

The rate of relaxation from steady-state force in rabbit psoas fiber bundles was examined before and after phosphorylation of myosin regulatory light chain (RLC). Relaxation was initiated using diazo-2, a photolabile Ca2+ chelator that has low Ca2+ binding affinity (K(Ca) = 4.5 x 10(5) M(-1)) before photolysis and high affinity (K(Ca) = 1.3 x 10(7) M(-1)) after photolysis. Before phosphorylating RLC, the half-times for relaxation initiated from 0.27 +/- 0.02, 0.51 +/- 0.03, and 0.61 +/- 0.03 Po were 90 +/- 6, 140 +/- 6, and 182 +/- 9 ms, respectively. After phosphorylation of RLC, the half-times for relaxation from 0.36 +/- 0.03 Po, 0.59 +/- 0.03 Po, and 0.65 +/- 0.02 Po were 197 +/- 35 ms, 184 +/- 35 ms, and 179 +/- 22 ms. This slowing of relaxation rates from steady-state forces less than 0.50 Po was also observed when bundles of fibers were bathed with N-ethylmaleimide-modified myosin S-1, a strongly binding cross-bridge derivative of S1. These results suggest that phosphorylation of RLC slows relaxation, most likely by slowing the apparent rate of transition of cross-bridges from strongly bound (force-generating) to weakly bound (non-force-generating) states, and reduces or eliminates Ca2+ and cross-bridge activation-depend...Continue Reading

References

Aug 1, 1975·European Journal of Biochemistry·J G WattersonM Kutzer
Jan 1, 1990·Proceedings of the National Academy of Sciences of the United States of America·H L Sweeney, J T Stull
Apr 20, 1986·Journal of Molecular Biology·D A Winkelmann, S Lowey
May 1, 1988·Proceedings of the National Academy of Sciences of the United States of America·B Brenner
Mar 1, 1982·The American Journal of Physiology·D R Manning, J T Stull
May 1, 1993·The American Journal of Physiology·H L SweeneyJ T Stull

❮ Previous
Next ❯

Citations

Mar 8, 2005·Pflügers Archiv : European journal of physiology·Corrado PoggesiRobert Stehle
Nov 30, 2010·Protoplasma·Janine E Radford, Rosemary G White
Mar 11, 2004·Journal of Molecular and Cellular Cardiology·Yasutake SaekiHaruo Sugi
May 14, 2008·The Journal of Biological Chemistry·Jian HuangJames T Stull
Aug 16, 2006·The Journal of General Physiology·Julian E StelzerRichard L Moss
Aug 25, 2011·Journal of Experimental Botany·Rosemary G White, Deborah A Barton
Jan 22, 2010·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Michael J GreenbergJeffrey R Moore
Dec 17, 2002·The Journal of Physiology·Ye LuoJack A Rall
Jan 15, 2016·Archives of Biochemistry and Biophysics·Hannah C PulcastroBertrand C W Tanner
Oct 14, 2008·Journal of Molecular and Cellular Cardiology·Alexander P SchwoererAli El-Armouche
Nov 21, 2014·Canadian Journal of Physiology and Pharmacology·William GittingsRene Vandenboom
Nov 30, 2016·Pflügers Archiv : European journal of physiology·Joshua BowslaughRene Vandenboom
Mar 31, 2018·European Journal of Applied Physiology·Samantha L KuzykJennifer M Jakobi
Jun 4, 2017·The Journal of Experimental Biology·Ian C SmithA Russell Tupling
Aug 28, 2004·American Journal of Physiology. Heart and Circulatory Physiology·M Charlotte OlssonRichard L Moss
Aug 5, 2006·Circulation Research·Richard L Moss, Daniel P Fitzsimons
Jun 1, 2008·Proteomics. Clinical Applications·Wenhai JinAnne M Murphy
Mar 5, 2008·Medicine and Science in Sports and Exercise·Nicolas BabaultMichel Pousson
Dec 13, 2006·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Kathleen Franks-SkibaRoger Cooke
May 17, 2007·The Journal of Biological Chemistry·Jeffrey W RyderJames T Stull
Oct 29, 2013·Journal of Muscle Research and Cell Motility·Rene VandenboomJames T Stull
Oct 12, 2012·Journal of Muscle Research and Cell Motility·William GittingsRene Vandenboom
Dec 14, 2018·The Journal of General Physiology·Jason J BreithauptBertrand C W Tanner
Feb 8, 2011·Journal of Muscle Research and Cell Motility·William GittingsRene Vandenboom
Apr 4, 2000·Physiological Reviews·A M GordonM Regnier
Mar 3, 2017·Journal of Muscle Research and Cell Motility·William GittingsRene Vandenboom
Jun 5, 1998·The American Journal of Physiology·P A WahrJ A Rall
Feb 3, 2011·Archives of Biochemistry and Biophysics·James T StullRene Vandenboom

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.