Stress-induced strain and brain region-specific activation of LINE-1 transposons in adult mice

AbstractTransposable elements (TEs) are conserved mobile genetic elements that are highly abundant in most eukaryotic genomes. Although the exact function of TEs is still largely unknown, it is increasingly clear that they are significantly modulated in response to stress in a wide range of organisms, either directly or indirectly through regulation of epigenetic silencing. We investigated the effect of repeated restraint stress (2 h a day, for 5 d) on transcription levels of LINE-1 (L1) retrotransposon in the brain of inbred BALB/c, DBA/2, C57BL/6N, and outbred CD1 mice. Repeated restraint stress induced strain and brain region-specific modulation of L1 activity. We observed a significant derepression of L1 transcription in the hippocampus (HIPP) of BALB/c mice and a significant downregulation in the hippocampus of C57BL/6N mice. No significant change in L1 expression was found in the other strains and brain regions. These findings indicate in mice the control of transposons expression as an additional m...