In unstressed cells, promotes SIAH1-mediated polyubiquitination and degradation of the serine/threonine-protein kinase HIPK2, probably by acting as a loading factor that potentiates complex formation between HIPK2 and ubiquitin ligase SIAH1 (PubMed:33591310). In response to DNA damage, localizes to the nucleus following phosphorylation by HIPK2 and modulates the expression of a subset of TP53/p53 target genes by binding to TP53 at target gene promoters (PubMed:33591310). This limits the expression of a number of cell death-mediating TP53 target genes, reducing DNA damage-induced cell death (PubMed:33591310). Enhances the binding of transcription factor TCF7L2/TCF4, a Wnt signaling pathway effector, to the promoters of target genes (By similarity). Plays a role in stress granule formation (PubMed:17984221).
