Heterochromatin: an epigenetic point of view in aging

Abstract

Aging: changes in genome infrastructure Biochemical pathways that alter the physical organization of the genome could play a prominent role in age-related cellular degeneration. Chromosomal DNA is wound around proteins known as histones; when such assemblies are packed closely together, the genes in compacted regions are generally silenced. Jong-Hyuk Lee, Vilhelm A. Bohr and colleagues at the US National Institutes of Health, Baltimore, have reviewed evidence linking these ‘heterochromatin’ regions of the genome to the aging process. They find that diseases associated with premature age-related tissue degeneration are frequently marked by abnormal activity in genes involved in heterochromatin remodeling. Several biochemical and genetic factors that have been shown to experimentally reverse biological aging in experimental settings also appear to affect heterochromatin remodeling. Closer examination of the relevant remodeling processes could therefore reveal fundamental biological drivers of age-related degeneration.