caution:Was originally (PubMed:1830244 and PubMed:8262387) thought to be a pre-mRNA splicing factor SF2 p32 subunit and to play a role in preventing exon skipping, ensuring the accuracy of splicing and regulating alternative splicing.,function:Not known. Binds to the globular "heads" of C1Q thus inhibiting C1 activation.,similarity:Belongs to the MAM33 family.,subunit:Interacts with Rubella virus capsid protein.,
Mitochondrion matrix . Nucleus . Nucleus, nucleolus . Cell membrane ; Peripheral membrane protein ; Extracellular side. Secreted. Cytoplasm . Seems to be predominantly localized to mitochondria. Secreted by activated lymphocytes. Localizes to the nucleolus when coexpressed with POLGARF (PubMed:32958672). Interaction with POLGARF is likely to result in prevention of C1QBP maturation and redirection from mitochondria to nucleoli (PubMed:32958672). .
Expressed on cell surface of peripheral blood cells (at protein level); Surface expression is reported for macrophages and monocyte-derived dendritic cells.