Biopolym. Cell. 1997; 13(6):474-478.
Structure and Function of Biopolymers
Homology of C-terminal non-catalytic domain of mammalian tyrosyl-tRNA synthetase with cylokine EMAP II and non-catalytic domains of methionyl- and phenylalanyl-tRNA synthetases
1Levanets O. V., 1Naidenov V. G., 1Odynets K. A., 1Woodmaska M. I., 1Matsuka G. Kh., 1Kornelyuk A. I.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680
Mammalian tyrosyl-tRNA synthetase contains C-terminal domain which is dispensable for the enzyme catalytic activity in the. aminoacylation of homologous tRNATyr. Cloning and sequencing cDNA which encodes this mammalian tyrosyl-tRNA synthetase was performed by the 3'-RACE method. Comparison of the amino acid sequence of the C-terminal domain of this mammalian tyrosyl-tRNA synthetase with other proteins using program BLASTP has shown the highest homology level (62.7 % identity) with a new cytokine, EMAP II, inducible by chemical cancerogenesis and corresponding to the p43 protein from high molecular weight aaRS complex of mammalians and also with non-catalytic C-terminal domains of methionyl-tRNA synthetases from nematode (62.7 %) and bacteria (27.7 %) and with N-terminal domain of the β-subunit of phenylalanyl-tRNA synthetase of E. coli (26.7 %). The hypothesis was proposed about possible forming of isolated C-domain as a result of the proteolytic digestion of tyrosyl-tRNA synthetase by intracellular proteases and about possible cytokinc-like activity of this C-domain.