RNA-SYNTHESIS IN ISOLATED-MITOCHONDRIA FROM BRAIN CORTEX, CEREBELLUM AND STEM - EVIDENCE OF DIFFERENT TRANSCRIPTIONAL RATES

1. A system for studying RNA synthesis in isolated sheep brain mitocho ndria was set up to investigate the transcriptional activity of differ ent brain regions (cortex, cerebellum and brain stem). in this system, mitochondrial DNA is transcribed and RNA processed in a way that fait hfully reproduces the in vivo process. 2. The comparison of the electr ophoretic patterns of the mitochondrial DNA transcription products sho wed that although they were qualitatively similar, there were large di fferences in the rate of mitochondrial DNA transcription of the three regions studied, cerebellum and brain stem showing transcriptional rat es which were 34 and 18% respectively of that of cerebral cortex.