TRIB2 couples UCP1 degradation to thermogenic adaptation and metabolic health

Genetic variation in TRIB2 has been associated with thermogenesis and fat accumulation, yet the underlying molecular mechanisms remain unclear. Uncoupling protein 1 (UCP1) is a key regulator of adaptive thermogenesis and energy expenditure. Here, we identified a human TRIB2 variant associated with migration patterns along latitude and environmental temperature, which destabilized its mRNA and is consistent with enhanced thermogenic capacity. We demonstrate that loss of Trib2 protects mice from diet-induced obesity, alleviates hepatic steatosis, and improves glucose tolerance and insulin sensitivity. Trib2 knockout mice exhibit elevated UCP1 expression in brown adipose tissue, leading to enhanced thermogenesis and increased heat production. Mechanistically, TRIB2 acts as a scaffold that binds UCP1 through its pseudokinase domain and recruits the E3 ligase MYCBP2, thereby promoting UCP1 ubiquitination and proteasomal degradation. Collectively, our findings reveal a previously unrecognized post-translational mechanism that regulates UCP1 stability and link TRIB2 function to both thermogenic adaptation and metabolic health, thereby highlighting TRIB2 as a potential therapeutic target for obesity and metabolic disorders.