The type II peroxiredoxin gene family of the mouse: molecular structure, expression and evolution

Peroxiredoxins (Prxs) are a newly defined family of antioxidant proteins that have been implicated, via their antioxidant activity, in a number of cellular functions, including cell proliferation and differentiation, protection of other proteins from oxidative damage, and intracellular signaling. We isolated genomic DNA sequences of the type II Prx (Prx II) gene from the mouse and analyzed their molecular genetic characteristics. In the mouse, the Prx II is found to form a small multigene family with three members. One of them, the Prx II-1 gene, is actively transcribed in a variety of adult tissues as well as in the developing embryos to produce a 1.1-kb mRNA. The Prx II-1 gene consists of six exons and five introns, and the whole transcription unit occupies about 4.5 kb in the mouse genome. The other two genes, Prx II-2 and Prx II-3, are encoded by single exons, and show 97.5 and 87% of nucleotide sequence homology with the Prx II-1 gene, respectively. Structural features of these genes and the results of RT-PCR analysis on RNAs from various tissue sources indicate that the Prx II-2 and Prx II-3 genes could be pseudogenes derived from the Prx II-1 gene by a mechanism involving retrotransposition. These results strongly suggest that only the Prx II-1 gene might be relevant for studying the function of the Prx II gene in the murine system.