Elite endurance athletes commonly have mutations that result in the loss of the protein α-actinin-3, which is a major component of fast-twitch muscle fibers. Loss of α-actinin-3 is associated with reduced power, increased endurance capacity, and enhanced response to endurance training.
In this issue of the Journal of Clinical Investigation , Kathryn North and colleagues at the Murdoch Children's Research Institute report that the loss of α-actinin-3 in fast-twitch muscle fibers, results in compensation by α-actinin-2. The presence of α-actinin-2 in fast-twitch muscle contributed to reprogramming these muscles through increased calcineurin signaling.
This study provides insight into how mutations in the gene encoding α-actinin-3 promote skeletal muscle adaptations that are advantageous to elite endurance athletes
TITLE: ACTN3 genotype influences muscle performance through the regulation of calcineurin signaling
AUTHOR CONTACT: Kathryn North
Murdoch Childrens Research Institute, Parkville, UNK, AUS
Phone: 61-3-8341-6226; Fax: 61-3-9348-1391; E-mail: kathryn.north@mcri.edu.au
View this article at: http://www.jci.org/articles/view/67691?key=56ae65251668e68f1365
Journal of Clinical Investigation