PRMT5 can methylate histone H2A at arginine-4 (H2AR3) (Pal et al. 2004). The histone-binding protein cooperator of PRMT5 (COPRS) guides PRMT5:WDR77 to methylate histone H4 arginine-4 (H4R3) rather than histone H3 arginine-9 (H3R8) (Lacroix et al. 2008) and may also be responsible for guiding PRMT5:WDR77 to methylate histone H2A arginine-4 (H2AR3).
Le Cam, A,
El Messaoudi, S,
histone-arginine N-methyltransferase activity of CCND1:CDK4:PRMT5:pT5-WDR77:COPRS [nucleoplasm]