Inositol Trisphosphate Receptor Mediated Ca2+ Signalling Stimulates Mitochondrial Function and Gene Expression in Core Myopathy Patients [Mouse arrays]

Elevated inositol trisphosphate receptor (IP3R) levels have been previously reported in skeletal muscle myotubes derived from patients with ryanodine receptor 1 (RyR1) mutation related core myopathies. However, the functional relevance and the relationship of IP3R mediated Ca2+ signalling with the pathophysiology of the disease is unclear. It has also been suggested that mitochondrial dysfunction underlies the development of central and diffuse multi-mini-cores, devoid of mitochondrial activity, a key pathological consequence of RyR1 mutations. Here we used muscle biopsies of central core and multi-minicore disease patients with RyR1 mutations, as well as cellular and in vivo mouse models of the disease to characterise whole genome and mitochondrial gene expression to assess if remodeling of skeletal muscle following loss of functional RyR1 mediates bioenergetic adaptation. 6 Samples were analyzed, with 3 biological replicates, 3 Controls and 5 Transgenic mice