Send to:

Choose Destination
See comment in PubMed Commons below
Proc Natl Acad Sci U S A. 1987 Mar;84(5):1286-9.

Poly(ADP-ribose) may signal changing metabolic conditions to the chromatin of mammalian cells.


In mammalian cells, NAD+ serves a dual role as a respiratory coenzyme and as a substrate for the posttranslational poly(ADP-ribose) modification of chromatin proteins, catalyzed by the nuclear enzyme poly(ADP-ribose) polymerase [NAD+ ADP-ribosyltransferase, EC]. Biological evidence strongly suggests that poly(ADP-ribosyl)ation modulates chromatin functions, although the precise molecular mechanisms involved have not yet been elucidated. Here we describe conditions for the rapid uptake of exogenously supplied NAD+ by living hepatocytes in primary monolayer culture. Raising the intracellular NAD+ concentration by 70% caused a 5-fold increase of chromatin-bound poly(ADP-ribose). We conclude that the constitutive level of posttranslational poly(ADP-ribose) modifications of chromatin proteins in mammalian cells is related to the availability of NAD+, which varies in different physiological and pathological states. We propose that poly-(ADP-ribose) may serve a hitherto unrecognized function by signaling altered metabolic conditions to the chromatin and thus modulate its functions in tune with changing metabolic states.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk