Highlights • Inactivation of the TCA cycle or dietary citrate elicits the UPRmt pathway • DVE-1 responds to citrate-induced UPRmt to regulate lipid metabolism • NHR-80 acts downstream of DVE-1 to transactivate lipogenesis under citrate stress Summary Mitochondria are known as the powerhouse of the cell. Dysfunction of mitochondria homeostasis induces the mitochondrial unfolded protein response (UPRmt), altering cellular metabolism. How cells sense the UPRmt to rewire metabolism is largely unknown.