TRIM40 is an E3 ubiquitin ligase that functions as a negative regulator of innate immune responses and has emerged as a multifunctional protein with disease-specific roles. As an interferon-stimulated gene, TRIM40 mediates ubiquitination and proteasomal degradation of pattern recognition receptors RIG-I and IFIH1, suppressing RLR signaling and antiviral interferon responses 1. TRIM40 also promotes NEMO neddylation to inhibit NF-κB activation [UniProt annotation]. Beyond immunity, TRIM40 functions as a tissue-context-dependent regulator: in the intestine, aberrantly upregulated TRIM40 drives inflammatory bowel disease by ubiquitinating ROCK1, disrupting cortical actin cytoskeleton and epithelial barrier integrity 2. In colorectal cancer, TRIM40 acts as a tumor suppressor, targeting ROCK1 for degradation and reducing c-Myc stability to increase p21 expression and inhibit proliferation 3. TRIM40 also ameliorates diabetic retinopathy by promoting K48-linked ubiquitination and degradation of DAB1, suppressing inflammatory signaling 4. In cardiac tissue, TRIM40 promotes pathological hypertrophy through K63-linked ubiquitination of PKN2 5. Genetic variants in TRIM40 are associated with worse motor and cognitive outcomes in Parkinson's disease 6. These findings reveal TRIM40 as a context-dependent regulator with therapeutic potential across multiple diseases.