Structural Studies of Eukaryotic Elongation Factors

Translation of the genetic information in the genes ofDNA is performed by the peptide-bond-synthesizing machinery of the ribosome. The chemical reaction producing polypeptides takes place at the peptidyl-transfer center of the ribosome and is an RNA-catalyzed process(Nissen et al. 2000b). However, the transitions betweenseveral different functional states of the ribosome are catalyzed by a number of protein factors only loosely associated with the ribosome (Garrett et al. 2000; Sonenberget al. 2000). The complete translation of genetic information into a given protein brings the ribosome and its factors through four different phases: (1) The initiationphase governed by start codons on mRNA and initiationfactors (IFs) where ribosomal subunits are assembled andwhere initiator tRNAs bind to the ribosome, (2) the elongation phase where codons on mRNA are matched withanticodons on tRNAs under the strict control of elongation factors (EFs), (3) the termination phase during whichstop codons are recognized by release factors (RFs) andfully synthesized polypeptides are released from the ribosome, and (4) the recycling phase where ribosomal subunits are dissociated from each other under the influenceof a ribosome recycling factor (RRF)...