SPPL2B
Description
The SPPL2B (signal peptide peptidase like 2B) is a protein-coding gene located on chromosome 19.
SPPL2B, also known as SPPL2B, is a human gene belonging to the signal peptide peptidase-like protease (SPPL) family. It contains the conserved active site motifs 'YD' and 'GxGD' within adjacent transmembrane domains (TMDs). This enzyme is found in endosomes, lysosomes, and the plasma membrane. It plays a role in innate and adaptive immunity by cleaving TNFα in activated dendritic cells. SPPL2B also modulates APP cleavage and Aβ production. Multiple transcript variants encoding different isoforms have been identified for this gene.
SPPL2B is an intramembrane-cleaving aspartic protease (I-CLiP) that cleaves type II membrane signal peptides within the hydrophobic plane of the membrane. It is involved in the processing of ITM2B and TNF. SPPL2B catalyzes the intramembrane cleavage of the anchored fragment of shed TNF-alpha (TNF), promoting the release of the intracellular domain (ICD) for signaling to the nucleus. SPPL2B might contribute to the regulation of innate and adaptive immunity. Additionally, it catalyzes the intramembrane cleavage of the simian foamy virus processed leader peptide gp18 of the envelope glycoprotein gp130, depending on prior ectodomain shedding by furin or furin-like proprotein convertase (PC)-mediated cleavage proteolysis.
SPPL2B is also known as IMP-4, IMP4, PSH4, PSL1.
