Genome-wide analysis of 6 month old hippocampal gene expression in Ogg1- and/or Mutyh-deficent mice

Oxidative DNA damage has been associated with cognitive decline. The Ogg1 and Mutyh DNA glycosylases cooperate to prevent mutations caused by 8-oxoG, a major premutagenic oxidative DNA base lesion. Here, we have examined behavior and cognitive function in mice deficient of these glycosylases. We found that Ogg1-/-Mutyh-/- mice were more active and less anxious and that their learning ability was impaired. In contrast, Mutyh-/- mice showed moderately improved memory compared to WT. There was no change in genomic 8-oxoG levels, suggesting that Ogg1 and Mutyh play minor roles in global repair in adult brain. Notably, transcriptome analysis of hippocampus revealed that differentially expressed genes in the mutant mice belong to pathways known to be involved in anxiety and cognitive function. Thus, beyond their involvement in DNA repair, Ogg1 and Mutyh modulate cognitive function and behavior, and related hippocampal gene expression, suggesting a novel role for 8-oxoG in regulating adaptive behavior. Overall design: The mRNA profiles from hippocampus of WT, Ogg1-/-, Mutyh-/- and Ogg1-/- Mutyh-/- C57BL/6 mice at 6month of age were generated by RNA sequencing using Illumina Hiseq 2000

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Bjørge MD, Hildrestrand GA, Scheffler K, Suganthan R, Rolseth V, Kuśnierczyk A, Rowe AD, Vågbø CB, Vetlesen S, Eide L, Slupphaug G, Nakabeppu Y, Bredy TW, Klungland A, Bjørås M