Figure 2. Proposed mechanical activation of signals leading to increased translation and ribosome biogenesis in skeletal muscle.

Dashed lines show the primary sensors of contractile activity, continuous lines show secondary mediators of signalling pathways proposed to ultimately upregulate protein synthesis. Calcium, focal adhesion kinases (FAK) and integrin linked kinases have each been proposed as mechanosensors that initiate the signal that generates greater subsequent activity of the mechanistic target of rapamycin complex 1 (mTORC1). The downstream effectors of mTORC1 are the 70 kDa ribosomal S6 protein kinase (S6K) and eukaryotic initiation factor 4E binding protein (4E‐BP) that have been shown to have key roles in promoting translation initiation and ribosome biogenesis (Philp et al. 2011).