SMURF1 is an E3 ubiquitin-protein ligase that functions as a critical regulator of multiple cellular pathways through targeted protein degradation. In the BMP signaling pathway, SMURF1 acts as a negative regulator by mediating ubiquitination and degradation of SMAD1 and SMAD5 1. The protein plays essential roles in autophagy regulation, controlling both initiation and maturation processes. SMURF1 ubiquitinates UVRAG at lysine residues 517 and 559, promoting autophagosome maturation by decreasing UVRAG association with RUBCN 2. Additionally, SMURF1 controls TFEB nuclear translocation for lysosomal biogenesis by interacting with LGALS3 and PPP3CB to form a regulatory complex that stabilizes TFEB 3. In cancer contexts, SMURF1 demonstrates oncogenic functions through novel mechanisms including PDK1 neddylation, which facilitates PI3K-Akt signaling in KRAS-mutated colorectal cancer 4. The protein also interacts with CAPG-171aa polypeptide, disrupting STK38-SMURF1 binding and preventing MEKK2 degradation in triple-negative breast cancer 5. SMURF1 has emerged as a therapeutic target, with allosteric inhibitors showing promise in treating pulmonary arterial hypertension by preventing BMPR2 ubiquitylation and normalizing BMP signaling 6. The protein's dysfunction contributes to vascular calcification in chr7 kidney disease through ER stress-mediated pathways 1.