Efficient cleavage of problematic tobacco etch virus (TEV)-protein arginine methyltransferase constructs.

Protein arginine methyltransferases (PRMTs) are enzymes that are involved in many biological processes. Several studies have shown that the identity of the N-terminal fusion tag affects the substrate selectivity of PRMTs. Therefore, to accurately study substrate recognition, it is imperative that a tagless PRMT be used. However, cleavage of tagged PRMTs has been problematic. We have developed a successful method by which untagged PRMTs can be made using a tobacco etch virus (TEV) cleavage site at the N-terminal domain. This method may be useful for cleaving other challenging target proteins that have the TEV protease recognition site.