REGULATION OF CYTOCHROME-C-OXIDASE AND F0F1-ATPASE SUBUNITS EXPRESSION IN RAT-BRAIN DURING AGING

In the present study we analyzed the age-dependent changes of mRNA lev els for cytochrome c oxidase and FoF1-ATP synthase subunits in rat cer ebral cortex and cerebellum. To establish whether the regulation of ex pression is transcriptional or post-transcriptional, the results were compared to those related to protein subunits levels, of the same enzy matic complexes, previously observed. The different patterns of age-re lated changes of mRNA subunits, in particular the lower increments, co mpared with those related to protein subunits, indicate that post-tran scriptional mechanisms of regulation might be involved in the coordina ted expression of the various subunits of each complex. Northern blott ing analyses of RNA from the cerebellum of rats at the various ages, s howed also differences in age-dependent patterns of transcription betw een cerebral cortex and cerebellum. Moreover, the major age-dependent changes of mitochondrial-encoded subunits, compared with the nuclear-e ncoded ones, previously observed at proteins level, occur also during transcription.