Key regulator of TP53BP1 required to stabilize TP53BP1 and regulate its recruitment to chromatin. Interacts (via the cytoplasmic part) with syndecan-4 (SDC4), but not with other syndecan proteins (PubMed:10633082). Colocalizes with SDC4 in ventral plasma membrane adhesion plaques. Ubiquitously expressed. Expressed in embryonic brain, eyes, gizzard, heart, intestine, kidney, liver, tibia and skin. Myristoylated in vitro; additional evidence is however required to confirm myristoylation in vivo. Belongs to the Nudix hydrolase family. TIRR subfamily. Although strongly related to the nudix NUDT16 protein, lacks the Nudix box and is therefore not related to the rest of the family. Lacks a number of residues which are necessary for hydrolase activity and does not play a role in U8 snoRNA decapping activity. Extended N-terminus.