Enables dimethylargininase activity. Involved in positive regulation of nitric oxide biosynthetic process and regulation of systemic arterial blood pressure. Located in mitochondrion. Is expressed in several structures, including brain; cardiovascular system; future prosencephalon; retina; and spinal cord. Human ortholog(s) of this gene implicated in cardiovascular system disease and hypertension. Orthologous to human DDAH1 (dimethylarginine dimethylaminohydrolase 1). [provided by Alliance of Genome Resources, Apr 2022]