title: Aging and chronic DNA damage response activate a regulatory pathway involving miR-29 and p53.
abstract: Aging is a multifactorial process that affects most of the biological functions of the organism and increases susceptibility to disease and death. Recent studies with animal models of accelerated aging have unveiled some mechanisms that also operate in physiological aging. However, little is known about the role of microRNAs (miRNAs) in this process. To address this question, we have analysed miRNA levels in Zmpste24-deficient mice, a model of Hutchinson-Gilford progeria syndrome. We have found that expression of the miR-29 family of miRNAs is markedly upregulated in Zmpste24(-/-) progeroid mice as well as during normal aging in mouse. Functional analysis revealed that this transcriptional activation of miR-29 is triggered in response to DNA damage and occurs in a p53-dependent manner since p53(-/-) murine fibroblasts do not increase miR-29 expression upon doxorubicin treatment. We have also found that miR-29 represses Ppm1d phosphatase, which in turn enhances p53 activity. Based on these results, we propose the existence of a novel regulatory circuitry involving miR-29, Ppm1d and p53, which is activated in aging and in response to DNA damage.
authors.affiliation: Departamento de Bioquímica y Biología Molecular, Instituto Universitario de Oncología, Universidad de Oviedo, Oviedo, Spain.
authors.forename: Alejandro P
authors.initials: AP
authors.lastname: Ugalde
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Ramsay
authors.forename: Jorge
authors.initials: J
authors.lastname: de la Rosa
authors.forename: Ignacio
authors.initials: I
authors.lastname: Varela
authors.forename: Guillermo
authors.initials: G
authors.lastname: Mariño
authors.forename: Juan
authors.initials: J
authors.lastname: Cadiñanos
authors.forename: Jun
authors.initials: J
authors.lastname: Lu
authors.forename: José Mp
authors.initials: JM
authors.lastname: Freije
authors.forename: Carlos
authors.initials: C
authors.lastname: López-Otín
mesh_terms: D000375:Aging; D000818:Animals; D002478:Cells, Cultured; D004249:DNA Damage; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000502:physiology; D005786:Gene Expression Regulation; D008565:Membrane Proteins / Q000172:deficiency; D008666:Metalloendopeptidases / Q000172:deficiency; D051379:Mice; D018345:Mice, Knockout; D035683:MicroRNAs / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000096:biosynthesis*; D000071636:Protein Phosphatase 2C; D017422:Sequence Analysis, DNA; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
chemical_list: C547014:MIRN29 microRNA, mouse; D008565:Membrane Proteins; D035683:MicroRNAs; D016159:Tumor Suppressor Protein p53; D010749:Phosphoprotein Phosphatases; C000607468:Ppm1d protein, mouse; D000071636:Protein Phosphatase 2C; D008666:Metalloendopeptidases; C491250:Zmpste24 protein, mouse