Ageing and PARP

Poly(ADP-ribosyl)ation, which is the posttranslational modification of proteins with poly(ADP-ribose), is catalysed by poly(ADP-ribose) polymerases. DNA-strand break induced catalytic activation of two PARP isoforms, namely PARP-1 and -2, are in involved in DNA base-excision repair and other repair pathways. A body of correlative data suggests a link between DNA-damage induced poly(ADP-ribosyl)ation and mammalian longevity. This notion was reinforced by recently published evidence for interactions between PARP-1 and the Werner syndrome protein, deficiency of which causes premature ageing in humans. Recent research on PARPs and poly(ADP-ribose) provides several candidate mechanisms through which poly(ADP-ribosyl)ation might contribute to keeping the ageing process at slow pace.