Abstract
Although there is evidence of alterations in brain protein phosphorylation patterns with age, it is not known if the protein kinases that phosphorylate only at tyrosine residues are involved in these changes. For this reason, we examined the age-related expression of pp60 c-src, a tyrosine protein kinase enriched in neural tissues, in whole brain of adult Fischer-344 rats. The pp60 c-src kinase activity was immunoprecipitated using a monoclonal antibody and the incorporation of [ 32P] from radiolabeled ATP into an exogenous substrate (casein) measured. The results showed that there was a substantial amount of pp60 c-src kinase activity in brain of the adult animals ranging in age from 4 to 23 months and that it was not significantly different among these groups. Also, immunoprecipitates obtained under conditions of monoclonal antibody excess and utilized for immunoblot analysis indicated that the relative levels of the pp60 c-src protein were unchanged in the same animals. These results suggest that, at the whole brain level, the pp60 c-src kinase has a stable turnover and that a high amount of activity is biologically important in brain of adult rats through early senescence.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have