Myosin mutations suppress Twitchin and troponin by altering the rate constant for attachment/detachment
Location
Science Center: Bent Corridor
Document Type
Poster
Start Date
4-26-2024 12:00 PM
End Date
4-26-2024 2:00 PM
Abstract
Our research focuses on understanding the regulation of muscle force production, particularly concerning force, velocity, work, and power, which are mediated by two protein switches. Mutations in these switches can lead to lethal heart diseases. Caenorhabditis elegans’ muscle is similar to human skeletal and cardiac muscle, allowing us to conduct physiological experiments regarding the mutations of the switches. In C. elegans, one of the switches is termed Twitchin, as mutations of it causes worms to twitch uncontrollably, and the other is termed troponin. We induced a mutation in myosin, altering the 462nd amino acid from alanine to valine. Interestingly, this mutation suppresses the twitching of a Twitchin mutant and the hypercontraction of a troponin mutant. Our study tested whether the myosin mutation reduces the number of interactions between actin and myosin, thus suppressing the twitching and hypercontraction of the Twitchin and troponin mutants. Myosin and actin interactions could be altered by decreasing the rate constant for attachment of myosin to actin or by increasing the detachment rate constant. We found diminished force and either normal or reduced fatigability in the mutated myosin worms, indicating a reduced attachment rate constant and possibly increased detachment rate constant of myosin from actin. These effects revert those caused by Twitchin and troponin mutations. Further research involves testing additional myosin mutations to validate our hypothesis that they similarly alter attachment and detachment rates, potentially offering insights into therapeutic interventions for aberrant muscle contractions.
Keywords:
Physiology, C. Elegans, Myosin Mutation
Recommended Citation
Rekate, Emma C., "Myosin mutations suppress Twitchin and troponin by altering the rate constant for attachment/detachment" (2024). Research Symposium. 1.
https://digitalcommons.oberlin.edu/researchsymp/2024/posters/1
Major
Biology
Project Mentor(s)
Taylor Allen, Biology
2024
Myosin mutations suppress Twitchin and troponin by altering the rate constant for attachment/detachment
Science Center: Bent Corridor
Our research focuses on understanding the regulation of muscle force production, particularly concerning force, velocity, work, and power, which are mediated by two protein switches. Mutations in these switches can lead to lethal heart diseases. Caenorhabditis elegans’ muscle is similar to human skeletal and cardiac muscle, allowing us to conduct physiological experiments regarding the mutations of the switches. In C. elegans, one of the switches is termed Twitchin, as mutations of it causes worms to twitch uncontrollably, and the other is termed troponin. We induced a mutation in myosin, altering the 462nd amino acid from alanine to valine. Interestingly, this mutation suppresses the twitching of a Twitchin mutant and the hypercontraction of a troponin mutant. Our study tested whether the myosin mutation reduces the number of interactions between actin and myosin, thus suppressing the twitching and hypercontraction of the Twitchin and troponin mutants. Myosin and actin interactions could be altered by decreasing the rate constant for attachment of myosin to actin or by increasing the detachment rate constant. We found diminished force and either normal or reduced fatigability in the mutated myosin worms, indicating a reduced attachment rate constant and possibly increased detachment rate constant of myosin from actin. These effects revert those caused by Twitchin and troponin mutations. Further research involves testing additional myosin mutations to validate our hypothesis that they similarly alter attachment and detachment rates, potentially offering insights into therapeutic interventions for aberrant muscle contractions.
