DNA polymerases δ and e in developing and aging rat brain

Abstract

Our study reveals the presence of DNA polymerases δ and e, participating in DNA replication and repair, along with already known polymerases α and β, in the developing and aging rat brain. This was achieved through a protocol that takes advantage of the reported differential sensitivities of different DNA polymerases towards certain inhibitors such as butylphenyl and butylanilino nucleotide analogs, 2′, 3′-dideoxythymidine triphosphate, the monoclonal antibody of human polymerase α and the use of preferred template primers and proliferating cell nuclear antigen. The results indicate that while polymerase β seems to be the predominant one, significant levels of polymerases α, δ and e are also present at all the postnatal ages studied and that the relative proportion of polymerase e increases with age. The data suggest that the rat brain is equipped with a sustained DNA repair capacity throughout the life span.