Location of tRNA on the ribosome

Abstract
Electron microscopy results of Lake [J. Mol. Biol. (1976) 105, 131–159] and Vasiliev [FEBS Lett. (1983) 155, 167–172] suggest that the 70 S ribosome has an open pocket or a cavity at the base of the L7/L12 stalk of the 50 S subunit, on the side of the 30 S subunit opposite to its bulge or platform. It is this pocket that is proposed here to be the site for binding and retention of two L‐shaped tRNA molecules on the ribosome. The model proposed is consistent with the facts about interactions of the protein L7/L12 with the elongation factors (EF‐Tu and EF‐G) involved in tRNA binding and translocation, as well as with the data available on the participation of proteins, S3, S5, S10, S14 and S19 in the formation of tRNA sites.