Animated crystallography of genetic code translation.

Abstract

Accurate genetic code translation is achieved by accumulation of hyper-specific chemical reactions. Transfer RNA (tRNA) acts as an adaptor molecule to link the genetic code (in messenger RNA) to a specific amino acid. tRNA itself has no ability to specifically bind with the cognate amino acid, while aminoacyltRNA synthetases (aaRSs) strictly recognize their cognate tRNA and amino acid, to synthesize a correctlypaired aminoacyl-tRNA, a substrate for ribosome. tRNA is initially transcribed by RNA polymerase as a precursor RNA with long extensions at the 5' and 3' terminus. Maturation of tRNA to a functional RNA requires processing of the extensional sequences and post-transcriptional chemical modifications, which ensures the specific aminoacylation of tRNA by the cognate aaRS. We have solved the crystal structure of the tRNA-maturating enzymes in a complex with tRNA (precursor) to especially elucidate the sophisticated mechanism of their highly specific chemical reactions. Our goal is to provide the animated crystallography or "movie" of the dynamic processes in the genetic code translation by capturing snapshots of the chemical reaction steps by X-ray crystallography.