Description
Primary mitochondrial respiratory chain (RC) diseases are heterogeneous in etiology and manifestations but collectively impair cellular energy metabolism.  To identify a common cellular response to RC disease, systems biology level transcriptome investigations were performed in human RC disease skeletal muscle and fibroblasts.  Global transcriptional and post-transcriptional dysregulation in a tissue-specific fashion was identified across diverse RC complex and genetic etiologies.  RC disease muscle was characterized by decreased transcription of cytosolic ribosomal proteins to reduce energy-intensive anabolic processes, increased transcription of mitochondrial ribosomal proteins, shortened 5'-UTRs to improve translational efficiency, and stabilization of 3'-UTRs containing AU-rich elements.  These same modifications in a reversed direction typified RC disease fibroblasts.  RC disease also dysregulated transcriptional networks related to basic nutrient-sensing signaling pathways, which collectively mediate many aspects of tissue-specific cellular responses to primary RC disease.  These findings support the utility of a systems biology approach to improve mechanistic understanding of mitochondrial RC disease.