Open Access
Methylation of the ribosomal RNA gene promoter is associated with aging and age‐related decline
Author(s) -
D'Aquila Patrizia,
Montesanto Alberto,
Mandalà Maurizio,
Garasto Sabrina,
Mari Vincenzo,
Corsonello Andrea,
Bellizzi Dina,
Passarino Giuseppe
Publication year - 2017
Publication title -
aging cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.103
H-Index - 140
eISSN - 1474-9726
pISSN - 1474-9718
DOI - 10.1111/acel.12603
Subject(s) - biology , cpg site , methylation , dna methylation , epigenetics , differentially methylated regions , ribosomal rna , gene , promoter , genetics , rna methylation , gene expression , microbiology and biotechnology , methyltransferase
Summary The transcription of ribosomal RNA genes (rDNA) is subject to epigenetic regulation, as it is abrogated by the methylation of CpG dinucleotides within their promoter region. Here, we investigated, through Sequenom platform, the age‐related methylation status of the CpG island falling into the rDNA promoter in 472 blood samples from 20‐ to 105‐year‐old humans and in different tissues (blood, heart, liver, kidney, and testis) of 15 rats 3–96 weeks old. In humans, we did not find a consistently significant correlation between CpG site methylation and chronological age. Furthermore, the methylation levels of one of the analyzed CpG sites were negatively associated with both cognitive performance and survival chance measured in a 9‐year follow‐up study. We consistently confirmed such result in a replication sample. In rats, the analysis of the homologous region in the tissues revealed the existence of increased methylation in old rats. rRNA expression data, in both humans and rats, were consistent with observed methylation patterns, with a lower expression of rRNA in highly methylated samples. As chronological and biological ages in rats of a given strain are likely to be much closer to each other than in humans, these results seem to provide the first evidence that epigenetic modifications of rDNA change over time according to the aging decline. Thus, the methylation profile of rDNA may represent a potential biomarker of aging.