Protein arginine methylation has emerged as an important mechanism for regulating the functions of proteins involved in diverse aspects of gene regulation such as transcriptional activation and repression, mRNA processing and nuclear-cytoplasmic shuttling. This modification is catalyzed by the PRMT family of enzymes which utilize intracellularS-adenosyl methionine as a cofactor to dimethylate-specific arginines found within many target proteins. The establishment of in vitro biochemical assays as well as the development of modification-specific antibodies, and more recently mass spectrometry, have increased our understanding of the mechanism of catalysis of the PRMT family of enzymes. In the following discussion, we present some of the more commonly used in vivo and in vitro techniques which can be utilized to study the mechanism of arginine methylation and its role in transcription.
