Mammalian aminoacyl-tRNA synthetases

Abstract

Publisher Summary This chapter discusses the recent developments of the studies on the structure-function relationship of mammalian synthetases, with emphasis on those features that are unique in mammalian synthetases and are for the most part absent in bacterial and yeast enzymes. Translation and transcription constitute the two major steps of gene expression in all organisms. Aminoacyl-tRNA synthetases (RSs) carry out the key role of the interpretation of the genetic code by the covalent attachment of specific amino acids to cognate tRNAs. The chapter discusses various classifications of mammalian aminoacyl-tRNA synthetases with several examples. The chapter also discusses the general structure of the RS complex dissociation and organization of the synthetases complex primary structures of mammalian synthetases. The chapter describes several distinct characteristics of N-terminal extensions in mammalian aminoacyl-tRNA synthetases. Mammalian RSs are obviously more complex than their bacterial or yeast counterparts. The structure and function of mammalian RSs are not well understood despite the tremendous progress that has been made at an increasingly rapid pace. The occurrence of synthetases complexes provides excellent models for the elucidation of basic principles in molecular interactions for highly complex machinery that requires efficiency, fidelity, and versatility. Synthetases are critically important in the interpretation of the genetic code and are responsible for the biosynthesis of all proteins in all cells and tissues. In view of the physiological roles of amino acids, elucidation of such relation is obviously important. The chapter concludes with the organization of synthetases and protein biosynthetic machinery.