catalytic activity:NAD(+) + (ADP-D-ribosyl)(n)-acceptor = nicotinamide + (ADP-D-ribosyl)(n+1)-acceptor.,function:May regulate vesicle trafficking and modulate the subcellular distribution of SLC2A4/GLUT4-vesicles. Has PARP activity and can modify TRF1, and thereby contribute to the regulation of telomere length.,PTM:ADP-ribosylated (-auto).,similarity:Contains 1 PARP catalytic domain.,similarity:Contains 1 SAM (sterile alpha motif) domain.,similarity:Contains 15 ANK repeats.,subcellular location:Associated with the Golgi and with juxtanuclear SLC2A4/GLUT4-vesicles. Also found around the pericentriolar matrix of mitotic centromeres. During interphase, a small fraction of TNKS2 is found in the nucleus, associated with TRF1.,subunit:Oligomerizes and associates with TNKS. Interacts with the cytoplasmic domain of LNPEP/Otase in SLC2A4/GLUT4-vesicles. Binds to the N-terminus of Grb14 and TRF1 with its ankyrin repeat region.,tissue specificity:Highly expressed in placenta, skeletal muscle, liver, brain, kidney, heart, thymus, spinal cord, lung, peripheral blood leukocytes, pancreas, lymph nodes, spleen, prostate, testis, ovary, small intestine, colon, mammary gland, breast and breast carcinoma, and in common-type meningioma. Highly expressed in fetal liver, heart and brain.,