Stress-dependent activation of myosin in the heart requires thin filament activation and thick filament mechanosensing

• DOI: 10.1073/pnas.2023706118
• Publication Date: 2021-04-13T21:03:34Z
• Authors: So-Jin Park-Holohan; Elisabetta Brunello; Thomas Kampourakis; Martin Rees; Malcolm Irving; Luca Fusi
• Keywords: Male; Sarcomeres; 0301 basic medicine; 570; Myosin Light Chains; muscle regulation; Myosins; Mechanotransduction, Cellular; 03 medical and health sciences; Stress, Physiological; Animals; Rats, Wistar; Cytoskeleton; Myocardium; 500; heart muscle; myosin-binding protein C; Heart; Biological Sciences; myosin motor; Rats; 3. Good health; Actin Cytoskeleton; Calcium; Muscle Contraction; Signal Transduction

Significance The efficiency of the heart as a pump depends on an autoregulatory mechanism, Frank–Starling law heart, that potentiates strength contraction in response to increase ventricular filling. Disruption this mechanism compromises ability blood, potentially leading failure. We used fluorescent probes myosin muscle cells investigate molecular basis mechanism. Our results show stronger at longer lengths is due calcium-dependent interfilament signaling pathway links stress sensing myosin-containing filaments with calcium activation actin-containing filaments. This can be targeted for treating