Replicative senescence is distinguishable from DNA damage-induced senescence by increased methylation of promoter of rDNA and reduced expression of rRNA

Publication date: Available online 27 September 2019Source: Mechanisms of Ageing and DevelopmentAuthor(s): Reiko Sanokawa-Akakura, Shin Akakura, Elena A. Ostrakhovitch, Siamak TabibzadehAbstractHuman fibroblasts become senescent after a limited number of replications or by diverse stresses, such as DNA damage. However, replicative and damage induced senescence are indistinguishable in respect to proliferation cessation and expression of senescence markers, senescence-associated β-galactosidase, p16 and p21. Here, we show that senescence types can be distinguished by reduced levels of 18S, 5.8S and 28S rRNA, in replicative but not induced senescence. We also demonstrate that promoter region of rRNA is hypermethylated in replicative senescence. The findings show that expression level of rRNA or methylation of its promoter can be used to distinguish between senescence types.

Source: Mechanisms of Ageing and Development - September 28, 2019 Category: Geriatrics Source Type: research