The arginine N-methyltransferase 2 protein (PRMT2, also known as HRMT1L1) is thought to act as a coactivator of ERα. The present results show the occurrence of a novel transcript by alternative polyadenylation in the human PRMT2 gene. We demonstrated that the newly identified intron-retaining PRMT2L2 transcript is functionally intact, efficiently translated into protein in vivo. PRMT2 and PRMT2L2 mRNA expression profiles overlap with the distribution of ERα, with the strongest abundance in estrogen target tissues. Transient co-transfection as...