Siva (IPR022773)

Short name: Siva_cd27-bd

Overlapping homologous superfamilies


Family relationships



Siva binds to the CD27 cytoplasmic tail. It has a DD homology region, a box-B-like ring finger, and a zinc finger-like domain. Overexpression of Siva in various cell lines induces apoptosis, suggesting an important role for Siva in the CD27-transduced apoptotic pathway [PMID: 9177220]. Siva-1 binds to and inhibits BCL-X(L)-mediated protection against UV radiation-induced apoptosis. Indeed, the unique amphipathic helical region (SAH) present in Siva-1 is required for its binding to BCL-X(L) and sensitising cells to UV radiation. Natural complexes of Siva-1/BCL-X(L) are detected in HUT78 and murine thymocyte, suggesting a potential role for Siva-1 in regulating T cell homeostasis [PMID: 12011449]. This family contains both Siva-1 and the shorter Siva-2 lacking the sequence coded by exon 2. It has been suggested that Siva-2 could regulate the function of Siva-1 [PMID: 10597319].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.