Abstract
Methylation of arginine is an additional option within the repertoire of post-translational modifications that proteins utilize for their communication with other partner proteins and nucleic acids, which ultimately contributes to cellular functions. Recent studies reveal that protein arginine methylation is more common and widespread than previously thought and that it is implicated in a number of key cellular processes including signal transduction. Two recent investigations have propelled this new world of protein modification into the immunological community by showing that TCR and CD28 signaling exploit this pathway. In contrast to other protein modifications utilized in intracellular signaling, arginine methylation seems to be long-lasting, raising interesting questions as to when, where and for what reason it can be utilized in the lymphocyte differentiation processes.