SPSB4
Description
The SPSB4 (splA/ryanodine receptor domain and SOCS box containing 4) is a protein-coding gene located on chromosome 3.
SPSB4 acts as a substrate recognition component of the Elongin BC-CUL2/5-SOCS-box protein (ECS) E3 ubiquitin-protein ligase complex. It mediates the ubiquitination and subsequent proteasomal degradation of target proteins, including NOS2, EphB2/CTF2, and NR1D1. SPSB4 negatively regulates nitric oxide (NO) production in activated macrophages by targeting NOS2 for degradation, thus limiting cellular toxicity. It also plays a role in regulating cell repulsive responses by degrading EphB2/CTF2 and in modulating cellular clock function by degrading the circadian transcriptional repressor NR1D1.
SPSB4 is also known as SSB-4, SSB4.
