Hepatic ureagenesis plays a predominant role in maintaining nitrogen and ammonia homeostasis in mammals. Disruption of ureagenesis leads to hyperammonemia, accompanied by hepatic encephalopathy and liver fibrosis. BAF60a is a subunit of the SWItch/Sucrose NonFermentable (SWI/SNF) complexes that regulates a series of metabolic pathways as a transcription factor. Zhang, Dong, et al. have elucidated a BAF60a-orchestrated upstream regulatory mechanism in the urea cycle and provide a mechanism through which steatotic hepatocytes produce ammonia via formation of a BAF60a-YB-1 complex.