Functions as antiviral protein and contributes to the defense against retroviral infections (, ). Acts as a capsid-specific restriction factor with the help of TRIM5 and prevents infection from non-host-adapted retroviruses . During influenza A virus infection, promotes programmed cell death by targeting ZBP1 for 'Lys-63'-linked polyubiquitination . In turn, promotes ZBP1 recruitment of RIPK3 to mediate virus-induced programmed necrosis . Negatively regulates the function of mitochondria by enhancing mitochondrial depolarization leading to cytochrome c release and mitochondria-dependent apoptosis . Promotes also the formation of multinucleated giant cells by means of cell fusion and phagocytosis in epithelial cells .
Subcellular locations: Cytoplasm, Mitochondrion
Localizes in cytoplasmic bodies together with TRIM5 and incoming HIV-1 capsids during infection.
Is the most abundant form. It is highly expressed in the placenta, spleen, colon and peripheral blood leukocytes.