cerebellum and hippocampus - deletor x wt

Progressive mitochondrial respiratory chain (RC) deficiency is associated with a wide spectrum of adult-onset degenerative diseases, as well as with normal aging. We have previously generated the Deletor mice to model late-onset progressive RC defects. Here we report novel tissue-specific pathways contributing to mitochondrial disease pathogenesis, identified by gene expression analysis. We found that RC-deficient muscle fibers secrete the fasting-induced hormone, fibroblast growth factor 21 (FGF21). This response leads to fatty acid recruitment from adipocytes and resistance to high-fat-diet induced obesity in mice, but does not affect glucose or insulin metabolism. FGF21 is also induced in the muscle of mitochondrial myopathy patients and in other RC-deficient mice. These data show that skeletal muscle is an endocrine organ, which signals its energy deficiency through FGF21. Furthermore, RC deficiency in single muscle fibers initiates a global starvation response. These data have important implications for conditions with primary or secondary RC deficiency. Mice overexpressing mutant Twinkle (C10ORF2) protein are the first animal model for Progressive External Ophtalmoplegia (PEO). Using PEO-model and wt-mice, cerebellum and hippocampus were analyzed for gene expression profile.