Enables protein-glutamine N-methyltransferase activity. Involved in peptidyl-glutamine methylation. Located in nucleus. Is expressed in several structures, including genitourinary system; gut; nervous system; sensory organ; and thymus. Orthologous to human N6AMT1 (N-6 adenine-specific DNA methyltransferase 1). [provided by Alliance of Genome Resources, Apr 2022]