Multiple forms of formamidopyrimidine-DNA glycosylase produced by alternative splicing in Arabidopsis thaliana

Formamidopyrimidine-DNA glycosylase (FPG) catalyzes the initial steps in th e repair of DNA containing oxidized purines. Two cDNA clones from Arabidops is thaliana encoding homologs of bacterial FPG have previously been describ ed. We now report that there are at least five additional variants of FPG m RNA in Arabidopsis, each apparently produced from the same gene (AtMMH) by alternative splicing. Thus, AtMMH, like at least four other genes in the ba se excision repair pathway of human cells, produces multiple forms of prote in product through alternative splicing. The variant forms of Arabidopsis F PG may be localized in different locations in the cells, may have different preferences for oxidized substrates, and/or may recruit different proteins that guide the subsequent steps of base excision repair. (C) 2001 Elsevier Science B.V. All rights reserved.