부산대학교 도서관

Aim The striated muscle activator of Rho signalling ( STARS) is a muscle-specific actin-binding protein. The STARS signalling pathway is activated by resistance exercise and is anticipated to play a role in signal mechanotransduction. Animal studies have reported a negative regulation of STARS signalling with age, but such regulation has not been investigated in humans. Methods Ten young (18-30 years) and 10 older (60-75 years) subjects completed an acute bout of resistance exercise. Gene and protein expression of members of the STARS signalling pathway and mi RNA expression of a subset of mi RNAs, predicted or known to target members of STARS signalling pathway, were measured in muscle biopsies collected pre-exercise and 2 h post-exercise. Results For the first time, we report a significant downregulation of the STARS protein in older subjects. However, there was no effect of age on the magnitude of STARS activation in response to an acute bout of exercise. Finally, we established that miR-628-5p, a mi RNA regulated by age and exercise, binds to the STARS 3' UTR to directly downregulate its transcription. Conclusion This study describes for the first time the resistance exercise-induced regulation of STARS signalling in skeletal muscle from older humans and identifies a new mi RNA involved in the transcriptional control of STARS. [ABSTRACT FROM AUTHOR]