Tankyrase Activity in Organs and Tissues of Mice.

Tankyrase, one of the NAD+ ADP-ribosyltransferases, is a target for drugs developed for their anticancer and other pharmacological activities. We designed an assay for estimation of the inhibition or activation of the enzyme in preclinical studies. In mice, the highest specific activity of tankyrase was observed in thymus, spleen, pancreas, and bone marrow. In murine liver, tankyrase is active in ontogenesis and during reparative regeneration; however, the basal activity is hardly detectable in normal liver and most of other organs of adult animals. We suggest that tankyrase is a part of the tissue growth and repair machinery, while its age-dependent inhibition, when an organism stops growing, turns on phenoptosis.