Biopolym. Cell. 1989; 5(4):5-14.
Models of elongation: two or three tRNA binding sites on the ribosome?
1Rodnina M. V.
  1. Institute of Molecular Biology and Genetics, Academy of Sciences of the Ukrainian SSR
    Kiev, USSR


Three-site models of the ribosomal elongation cycle are discussed. The controversial experimental data on the interaction between tRNA and the third ribosomal site (E) are presented. The functional role of the E site in the translocation process is considered. The alternative three-site model based on different tRNA orientation during the elongation cycle on the ribosome is discussed. It is concluded that the classical two-site model is to be extended on the basis of the recent experimental data.


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