Enables hydroxymethylglutaryl-CoA synthase activity; isomerase activity; and organic acid binding activity. Involved in several processes, including animal organ development; cellular response to cholesterol; and cellular response to follicle-stimulating hormone stimulus. Located in cytosol. Biomarker of obesity. Orthologous to human HMGCS1 (3-hydroxy-3-methylglutaryl-CoA synthase 1). [provided by Alliance of Genome Resources, Apr 2022]