Antibodies against the mono-methylated Arginine-Glycine repeat (MMA-RG) of the Epstein-Barr virus nuclear antigen 1 (EBNA1) identify potential cellular proteins targeted in viral transformation

The viral nuclear antigen 1 (EBNA1) of Epstein Barr (EBV) features two functionally redundant Arginine-Glycine (RG) repeats that contain symmetrically and asymmetrically di-methylated (SDMA/ADMA) and also mono-methylated (MMA) Arginine residues. We generated mouse monoclonal antibodies against the mono-methylated RG-repeat between aa 328-377. In addition to detect MMA-EBNA1, we aimed at the identification of cellular proteins that are bound to MMA-modified EBNA1 in EBV-positive Raji cells.