Non-canonical functions of aminoacyl-tRNA synthetases.

The basic function of aminoacyl-tRNA synthetases (aaRSs) is an activation of the amino acids and their transfer to specific RNAs. In addition to this key role in protein biosynthesis, the enzymes of this group participate in other cell processes. aaRSs regulate the expression of some genes, not only their own. The regulation is carried out on the level of transcription, processing of mRNA, and translation. They catalyze the synthesis of dinucleoside oligophosphates and thus indirectly influence many other cell functions. Tyrosyl-tRNA synthetase was shown to have cytokine activities. Some aaRSs interact specifically with other proteins. Thus, aminoacyl-tRNA synthetases are involved in the regulation of the multiple processes of living cells. In this review we summarize the available data on unusual activities of aaRSs.