Epigenetics and Ageing

Abstract

The term epigenetics refers to the heritable alterations not due to changes in DNA sequences, which modulate the individual phenotype by modulating the expression and the activity of genes (Armstrong, Epigenetics, Garland Science, New York, 2013; Pinel et al., BioSocieties 13:276-303, 2018). In fact, DNA methylation and histone modification, that are covalent and non-covalent modifications of DNA and histone proteins, alter DNA accessibility and overall chromatin structure, thereby regulating patterns of gene expression (Huang et al., Epigenomics 6:73-88, 2014; Allis and Jenuwein, Nat Rev Genet 17:487-500, 2016). More recently, epigenetics has also addressed the role of small non-coding RNAs in influencing gene expression levels (Moazed, Nature 457:413-420, 2009; Goldstein et al., Genome Res 27:462-470, 2017). As these processes are influenced by environmental factors, epigenetics is often considered as a bridge between genome and environment in the definition of phenotype (Norouzitallab et al., Sci Total Environ 647:1281-1293, 2018). Many evidences have suggested in the last decade that ageing, which is deeply influenced by genetics, environment and their interaction, may be influenced by (and at the same time influence) epigenetics. In this chapter, we review both epigenetic modifications of DNA structure and the role of non-coding RNAs and their relationship with ageing and age-related phenotypes.