Fbxo3

FBXO3 (F-box protein 3) is a substrate-recognition component of the SCF (SKP1-CUL1-F-box) ubiquitin E3 ligase complex that regulates protein ubiquitination and proteasomal degradation pathways^[1][2]. Mechanistically, FBXO3 promotes degradation of FBXL2, a negative regulator of tumor necrosis factor receptor-associated factor (TRAF) signaling, thereby enhancing TRAF-dependent cytokine production and inflammatory responses^[1][2][3]. Through this ubiquitin-mediated regulatory axis, FBXO3 functions as an important controller of cytokine secretion in human inflammatory cells and contributes to the fine-tuning of innate immune signaling networks^[1][3]. In disease-related studies, elevated FBXO3 activity has been linked to pathological inflammation, including experimental models of atherosclerosis and cerebral ischemia/reperfusion injury, where FBXO3-driven ubiquitination events amplify inflammatory signaling and tissue damage^[4][5]. Additional evidence indicates that FBXO3 can regulate the stability of other signaling proteins, including Smurf1 and HIPK2, further supporting its broader role in cellular protein quality control and stress-response pathways^[5][6]. Compared with related F-box proteins, FBXO3 is distinguished by its prominent regulation of the FBXL2-TRAF inflammatory signaling module, a mechanism repeatedly identified across inflammatory disease models^[1][2][3]. For experimental applications, pharmacological inhibition or genetic suppression of FBXO3 has been used to attenuate inflammatory responses, making FBXO3 a valuable target for mechanistic studies of ubiquitin signaling, cytokine regulation, and inflammation-associated disease processes^[1][5].