I graduated from the University of York in 2013 with a First class degree in Molecular Cell Biology.
Why do your muscles grow in response to exercise? Though the causal relationship between exercise and muscle growth is intuitive and well known, the molecular underpinnings of this process are less understood. Clearly, muscles normally have the means to translate mechanical input into growth signalling pathways. The z-disc of the skeletal muscle sarcomere, acting as an anchor point for the contractile proteins of muscle, would appear to be an ideal site for this process to occur.
The ky/ky mouse is a model of genetic kyphoscoliosis (abnormal spine curvature) lacking the z-disc protein KY. It has smaller, weaker muscles and has been shown to be unable to induce muscle growth in response to mechanical overloading. Investigation of the KY protein and the ky/ky mouse model, as well as other genetic models such as zebrafish, may provide some fundamental answers as to how muscles detect and respond to mechanical forces. This could in turn provide therapeutic targets to aid muscle growth, preventing the muscle wastage associated with age and a broad range of diseases from muscular dystrophies to cancer.