Function of the extra 5'-phosphate carried by histidine tRNA.

Michel Fromant (1) , Pierre Plateau (1) , Sylvain Blanquet (1)

1 BIOC - Laboratoire de Biochimie de l'Ecole polytechnique

Among elongator tRNAs, tRNA specific for histidine has the peculiarity to possess one extra nucleotide at position -1. This nucleotide is believed to be responsible for recognition by histidyl-tRNA synthetase. Here, we show that, in fact, it is the phosphate 5' to the extra nucleotide which mainly supports the efficiency of the tRNA aminoacylation reaction catalyzed by Escherichia coli histidyl-tRNA synthetase. In the case of the reaction of E. coli peptidyl-tRNA hydrolase, this atypical phosphate is dispensable. Instead, peptidyl-tRNA hydrolase recognizes the phosphate of the phosphodiester bond between residues -1 and +1 of tRNA(His). Recognition of the +1 phosphate of tRNA(His) by peptidyl-tRNA hydrolase resembles, therefore, that of the 5'-terminal phosphate of other elongator tRNAs.

Domaines: Biochimie, Biologie Moléculaire

Michel Fromant, Pierre Plateau, Sylvain Blanquet. Function of the extra 5'-phosphate carried by histidine tRNA.. Biochemistry, 2000, 39 (14), pp.4062-7. ⟨10.1021/bi9923297⟩. ⟨hal-00771808⟩