Enables modified amino acid binding activity and protein-arginine omega-N asymmetric methyltransferase activity. Involved in dendritic spine morphogenesis and peptidyl-arginine methylation, to asymmetrical-dimethyl arginine. Located in cytoplasm. Biomarker of asthma. Orthologous to human PRMT3 (protein arginine methyltransferase 3). [provided by Alliance of Genome Resources, Apr 2022]