The ribosomal elongation cycle and the movement of tRNAs across the ribosome.
Ribosome research has reached an exciting state, where two lines of experimental research have considerably improved our understanding of the ribosomal functions. On one hand, functional analysis has elucidated principles of both the decoding process and the tRNA movement on the ribosome during translocation. Experimental data leading to current competing models of the ribosomal elongation cycle can be reconciled by a new model, the alpha-epsilon model, according to which both tRNAs are tightly bound to a movable ribosomal domain. This alpha-epsilon domain carries the tRNA2.mRNA complex from the A and P sites to the P and E sites in the course of translocation maintaining the binding of both tRNAs. On the other hand, the location of tRNAs within the elongating ribosome can be directly determined for the first time by neutron scattering and electron microscopy. Both lines of evidence complement each other and define a frame for the first experimentally sound functional model of the elongating ribosome.
Nierhaus
K H
KH
Max-Planck-Institut für Molekulare Genetik, Berlin, Germany.
Stuhrmann
H B
HB
Svergun
D
D
D008958:Models, Molecular; D010441:Peptide Chain Elongation, Translational / Q000502:physiology*; D012343:RNA, Transfer / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*
D012343:RNA, Transfer