FEATURES

FAMILY

DESCRIPTION

Also known as SPPL3_HUMAN, SPPL3, IMP2, PSL4. Intramembrane-cleaving aspartic protease (I-CLiP) that cleaves type II membrane protein substrates in or close to their luminal transmembrane domain boundaries (PubMed:16873890, PubMed:25354954, PubMed:25827571). Acts like a sheddase by mediating the proteolytic release and secretion of active site-containing ectodomains of glycan-modifiying glycosidase and glycosyltransferase enzymes such as MGAT5, B4GAT1 and B4GALT1 (PubMed:25354954, PubMed:25827571). Catalyzes the intramembrane cleavage of the envelope glycoprotein gp130 and/or the leader peptide gp18LP of the simian foamy virus independent of prior ectodomain shedding by furin or furin-like proprotein convertase (PC)-mediated cleavage proteolysis (PubMed:23132852). May also have the ability to serve as a shedding protease for subsequent intramembrane proteolysis by SPPL2A and SPPL2B of the envelope glycoprotein gp130 (PubMed:23132852). Plays a role in the regulation of cellular glycosylation processes (PubMed:25354954). Required to link T-cell antigen receptor (TCR) and calcineurin-NFAT signaling cascades in lymphocytes by promoting the association of STIM1 and ORAI1 during store-operated calcium entry (SOCE) in a protease-independent manner (PubMed:25384971). Monomer (PubMed:15385547, PubMed:15998642, PubMed:16873890). Homodimer (PubMed:15385547, PubMed:15998642, PubMed:16873890). Interacts with STIM1 (via the transmembrane region and the SOAR/CAD domain); the interaction promotes the binding of STIM1 to ORAI1 (PubMed:25384971). Interacts with the simian foamy virus envelope glycoprotein gp130 and its processed leader peptide gp18LP; preferentially interacts with the envelope glycoprotein gp130 (PubMed:23132852).

EXTERNAL LINKS

SPPL3

Signal peptide peptidase-like 3

SPPL3

Molecular Synopsis