CPEB3
Description
The CPEB3 (cytoplasmic polyadenylation element binding protein 3) is a protein-coding gene located on chromosome 10.
CPEB3 (Cytoplasmic polyadenylation element-binding protein 3) is a sequence-specific RNA-binding protein that acts as a translational repressor in the basal unstimulated state but becomes a translational activator following neuronal stimulation. Unlike CPEB1, it does not bind to the cytoplasmic polyadenylation element (CPE), a uridine-rich sequence element within the mRNA 3'UTR, but instead binds to a U-rich loop within a stem-loop structure. CPEB3 is essential for the consolidation and maintenance of hippocampal-based long term memory. In the resting state, it binds to the mRNA 3'UTR of the glutamate receptors GRIA2/GLUR2 mRNA and negatively regulates their translation. It also represses the translation of DLG4, GRIN1, GRIN2A, and GRIN2B. Upon activation, CPEB3 acts as a translational activator of GRIA1 and GRIA2. In the basal state, CPEB3 suppresses SUMO2 translation but activates it following neuronal stimulation. CPEB3 binds to the 3'UTR of TRPV1 mRNA and represses TRPV1 translation, which is necessary for maintaining normal thermoception. CPEB3 binds actin mRNA, leading to actin translational repression in the resting state and to translational activation after neuronal stimulation. CPEB3 negatively regulates target mRNA levels by binding to TOB1, which recruits CNOT7/CAF1 to a ternary complex, leading to target mRNA deadenylation and decay (PubMed:21336257). In addition to its role in translation, CPEB3 binds to and inhibits the transcriptional activation activity of STAT5B without affecting its dimerization or DNA-binding activity. This, in turn, represses transcription of the STAT5B target gene EGFR, which has been shown to play a role in enhancing learning and memory performance (PubMed:20639532). Unlike CPEB1, CPEB2, and CPEB4, CPEB3 is not required for cell cycle progression (PubMed:26398195).
CPEB3 is also known as -.
