Age-Dependent Increase in C7-1 Gene Expression in Rat Frontal Cortex

We have previously reported that a fragment of mRNA, denoted as C7-1, which expression was significantly increased in the frontal cortex of aged rats. In the present study, we have cloned and sequenced the full length cDNA of the C7-1 gene. We have found that the open reading frame of this gene encoded a 463-amino-acid protein, which shared 84% identity in amino acid sequence with a subunit of vacuolar H+-ATPase (V-ATPase). Further Northern blot analysis revealed that there was an age-dependent increase in C7-1 gene expression in rat frontal cortex, but not in other brain areas. Moreover, application of C7-1 antisense oligonucleotide to cortical neuronal cultures markedly inhibited cell survival. These results together suggest that C7-1 is a marker for the aging process and that upregulation of C7-1 may be important in maintaining the normal function of V-ATPase during aging.cortical neuronal cultures markedly inhibited cell survival.