The function of Ensembl gene identifier ENSG00000110171 (TRIM3, tripartite motif containing 3) is as follows. E3 ubiquitin ligase that plays essential roles in neuronal functions such as regulation of neuronal plasticity, learning, and memory (By similarity). In addition to its neuronal functions, participates in other biological processes such as innate immunity or cell cycle regulation. Component of the cytoskeleton-associated recycling or transport complex in neurons, polyubiquitinates gamma- actin, thus regulating neuronal plasticity, learning, and memory (By similarity). Ubiquitinates postsynaptic scaffold GKAP, a neuronal substrate involved in synaptic remodeling and thereby modulates dendritic spine morphology (By similarity). Positively regulates motility of microtubule-dependent motor protein KIF21B (By similarity). Induces growth arrest via its RING-dependent E3 ligase activity and ubiquitinates CDKN1A (PubMed:24393003). Positively regulates TLR3- mediated signaling by mediating 'Lys-63'-linked polyubiquitination of TLR3 (PubMed:32878999). In turn, promotes the recognition and sorting of polyubiquitinated TLR3 by the ESCRT complexes (PubMed:32878999). {ECO:0000250|UniProtKB:Q9R1R2, ECO:0000269|PubMed:15772161, ECO:0000269|PubMed:24393003, ECO:0000269|PubMed:32878999}.