Enables protein-lysine N-methyltransferase activity. Involved in protein methylation. Acts upstream of or within cellular response to hormone stimulus; regulation of release of sequestered calcium ion into cytosol by sarcoplasmic reticulum; and skeletal muscle tissue development. Predicted to be located in nucleus. Predicted to be part of protein-containing complex. Predicted to be active in cytosol. Is expressed in alimentary system; diaphragm; genitourinary system; skeletal muscle; and skin. Orthologous to human METTL21C (methyltransferase 21C, AARS1 lysine). [provided by Alliance of Genome Resources, Apr 2022]