S-adenosyl-L-methionine-dependent protein-arginine N-methyltransferase that can catalyze both the mono- and symmetric (type II) dimethylation of the guanidino nitrogens of arginine residues in target proteins (By similarity). Positively modulates the shk1 kinase function. May be a mediator of hyperosmotic stress response (PubMed:11278267). Interacts with the N-terminal regulatory domain of shk1. Shk1, cdc42 and skb1 are able to form a ternary complex in vivo. Localizes to cell ends, sites of septation, and nuclei. Belongs to the class I-like SAM-binding methyltransferase superfamily. Protein arginine N-methyltransferase family.