Poly-ADP-ribosyltransferase involved in various processes such as Wnt signaling pathway, telomere length and vesicle trafficking (PubMed:11739745, PubMed:11802774, PubMed:19759537, PubMed:21478859, PubMed:23622245, PubMed:25043379). Acts as an activator of the Wnt signaling pathway by mediating poly-ADP-ribosylation of AXIN1 and AXIN2, 2 key components of the beta-catenin destruction complex: poly- ADP-ribosylated target proteins are recognized by RNF146, which mediates their ubiquitination and subsequent degradation (PubMed:19759537, PubMed:21478859). Also mediates poly-ADP-ribosylation of BLZF1 and CASC3, followed by recruitment of RNF146 and subsequent ubiquitination (PubMed:21478859). Mediates poly-ADP-ribosylation of TERF1, thereby contributing to the regulation of telomere length (PubMed:11739745). Stimulates 26S proteasome activity (PubMed:23622245). {ECO:0000269|PubMed:11739745, ECO:0000269|PubMed:11802774, ECO:0000269|PubMed:19759537, ECO:0000269|PubMed:21478859, ECO:0000269|PubMed:23622245, ECO:0000269|PubMed:25043379}. This is the function of Ensembl gene identifier ENSG00000107854 (TNKS2, tankyrase 2).