Orphan nuclear receptor (PubMed:25981666). Regulates expression of genes involved in fat metabolism and in maintaining homeostasis of fatty acid saturation, such as lipid desaturase fat-7, and acyl-CoA synthetase acs-2 (PubMed:25981666, PubMed:15719061). May form part of a negative feedback loop with fat-7 to limit beta-oxidation, in which it stimulates expression of fat-7 and acs-2, and in turn fat-7 indirectly inhibits acs-2 and other genes also involved in beta-oxidation (PubMed:15719061). The 9aaTAD motif is a transactivation domain present in a large number of yeast and animal transcription factors. RNAi-mediated knockdown eliminates the effect of C11 or C12 chain fatty acids in activating fat-7 expression and blocks overexpression of fat-7 in acdh-11 mutants (PubMed:25981666). Increased ratio of stearic acid to oleic acid (C18:0/C18:1n9) (PubMed:15719061). Drastically reduced life span (PubMed:15719061). Belongs to the nuclear hormone receptor family.