MRNA Decay Factor AUF1 Maintains Normal Aging, Telomere Maintenance, and Suppression of Senescence by Activation of Telomerase Transcription

Department of Microbiology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA.
Molecular cell (Impact Factor: 14.02). 05/2012; 47(1):5-15. DOI: 10.1016/j.molcel.2012.04.019
Source: PubMed


Inflammation is associated with DNA damage, cellular senescence, and aging. Cessation of the inflammatory cytokine response is mediated in part through cytokine mRNA degradation facilitated by RNA-binding proteins, including AUF1. We report a major function of AUF1-it activates telomerase expression, suppresses cellular senescence, and maintains normal aging. AUF1-deficient mice undergo striking telomere erosion, markedly increased DNA damage responses at telomere ends, pronounced cellular senescence, and rapid premature aging that increases with successive generations, which can be rescued in AUF1 knockout mice and their cultured cells by resupplying AUF1 expression. AUF1 binds and strongly activates the transcription promoter for telomerase catalytic subunit Tert. In addition to directing inflammatory cytokine mRNA decay, AUF1 destabilizes cell-cycle checkpoint mRNAs, preventing cellular senescence. Thus, a single gene, AUF1, links maintenance of telomere length and normal aging to attenuation of inflammatory cytokine expression and inhibition of cellular senescence.

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