Abstract
Base excision repair (BER) is initiated with excision of damaged bases by DNA glycosylases. DNA glycosylase NEIL1 is a homolog of E. coli endonuclease VIII and identified in human and mouse cells. In only mouse cells, a couple of variants of Neil1 mRNA have been reported. Putative “NEIL1 protein (NCBI AAH43297)” mRNA (variant1) has shorter nucleotide sequence than NEIL1. Putative “unnamed protein (NCBI BAC30707)” mRNA (variant2) has a stop codon at the 436th of variant1 and 10 bases insert just after the codon. However, there is no report about functions of these variants. In this study, we constructed expression systems of these variants and examined activities of recombinant proteins. To do cloning of variants genes, we examined expression of mRNA of variants in various mouse organs. We performed RT-PCR with primer set 1, which amplify NEIL1 and variant1, and primer set 2 to amplify NEIL1, variant1, and variant2. Expression of either NEIL1 or variant1 was observed in brain, heart, liver, and kidney. On the other hand, amplification products were only observed using primer set 2 with RNA samples from lungs, stomach, and spleen suggesting only variant2 expresses in these organs. We constructed expression systems of these variants and the characterization of these recombinant proteins is in progress.
