Enables several functions, including DNA-binding transcription activator activity, RNA polymerase II-specific; long-chain fatty acid binding activity; and long-chain fatty acyl-CoA binding activity. Involved in several processes, including hepatocyte differentiation; negative regulation of peptidyl-tyrosine phosphorylation; and regulation of cellular biosynthetic process. Located in cytoplasm and nucleus. Biomarker of hepatocellular carcinoma and type 2 diabetes mellitus. Human ortholog(s) of this gene implicated in Fanconi renotubular syndrome 4; familial combined hyperlipidemia; hypoglycemia; maturity-onset diabetes of the young type 1; and type 2 diabetes mellitus. Orthologous to human HNF4A (hepatocyte nuclear factor 4 alpha). [provided by Alliance of Genome Resources, Apr 2022]