Analysis of protein arginine methylation and protein arginine-methyltransferase activity

Posttranslational modification of proteins allows cells to adapt and react quickly to their environment beyond the boundaries set forth by genetic code. Arginine methylation, a protein modification discovered almost 30 years ago, has recently experienced a renewed interest as several new arginine methyltransferases have been identified and numerous proteins were found to be regulated by methylation on arginine residues. Until recently, the detection of arginine methylation required the use of chromatography and mass-spectrometrical analysis. The following protocol provides guidelines for the straightforward identification of arginine-methylated proteins, made possible by the availability of novel, commercially available reagents.