Tankyrase-1 is an enzyme that in humans is encoded by the TNKS gene. Tankyrases 1 and 2 (TNKS1/PARP5A and TNKS2/PARP5B/PARP5C) are proteins with poly(ADP-ribose) polymerase activity. Human tankyrases post-translationally modify multiple proteins involved in processes including maintenance of telomere length, sister telomere association, insulin responsiveness, spindle assembly and trafficking of glut4-containing vesicles. Recently tankyrases have been shown be involved in the wnt signaling pathway. Tankyrases bind directly to axin, a member of the 'destruction complex' involved in
 beta-catenin degradation. Inhibition of tankyrase stabilizes axin, increases the activity of the destruction
 complex and promotes degradation of beta-catenin. Tankyrases are therefore an attractive target anticancer
 therapies.
Function: May regulate vesicle trafficking and modulate the subcellular distribution of SLC2A4/GLUT4-vesicles. Has PARP activity and can modify TERF1, and thereby contribute to the regulation of telomere length.