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Analysis of Tubular Membrane Networks in Cardiac Myocytes from Atria and Ventricles
Published on: October 15, 2014
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Microtubule mechanics in the working myocyte
Patrick Robison1, Benjamin L Prosser1
1Department of Physiology, Pennsylvania Muscle Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA.
The Journal of Physiology
|January 25, 2017
Summary
Cardiac microtubules (MTs) function as tunable springs, with detyrosination altering myocyte mechanics and mechanosignalling. This discovery offers new therapeutic targets for heart conditions.
Area of Science:
- Cardiovascular Biology
- Cellular Mechanics
- Cytoskeletal Dynamics
Background:
- The mechanical function of cardiac microtubules (MTs) has been debated, with early studies yielding inconsistent results.
- Recent technological advancements enable a clearer understanding of cytoskeletal roles.
Purpose of the Study:
- To investigate the mechanical role of cardiac microtubules in myocytes.
- To explore how post-translational modifications (PTMs) influence MT function and cardiac mechanics.
Main Methods:
- Direct observation of microtubules in working cardiac myocytes.
- Analysis of microtubule post-translational modifications, specifically detyrosination.
- Assessment of myocyte stiffness, contractility, and mechanosignalling.
Main Results:
- Cardiac MTs exhibit a tunable, spring-like mechanical function.
- Detyrosination of MTs promotes interactions with intermediate filaments, affecting sarcomeric complexation.
- These interactions alter myocyte stiffness, contractility, and mechanosignalling pathways.
Conclusions:
- Cardiac cytoskeletal regulation involves polymerization, binding partners, and PTMs, creating functionally distinct MT subsets.
- Mechanically distinct MT subsets represent novel therapeutic targets for cardiac diseases.
- The evolutionary implications of tunable cytoskeletal mechanics warrant further investigation.
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