Codon-anticodon interaction at the ribosomal E site.

H J Rheinberger; H Sternbach; K H Nierhaus

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PubMed · 2424905

Codon-anticodon interaction at the ribosomal E site.

H J Rheinberger·H Sternbach·K H Nierhaus

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Abstract

The question of whether or not the tRNA at the third ribosomal binding site specific for deacylated tRNA (E site) undergoes codon-anticodon interaction was analyzed as follows. Poly(U)-programmed ribosomes each carrying two [14C]tRNAPhe molecules were subjected to a chasing experiment using various tRNA species. At 0 degree C Ac[3H]Phe-tRNAPhe did not trigger any chasing whereas deacylated cognate tRNAPhe provoked a strong effect; non-cognate tRNALys was totally ineffective. This indicates that the second [14C]tRNAPhe cannot be present at the A site but rather at the E site (confirming previous observations). In the presence of poly(U) or poly(A) ribosomes bound the cognate tRNA practically exclusively as second deacylated tRNA, i.e. [14C]tRNAPhe and [14C]tRNALys, respectively. Thus, the second deacylated tRNA binds in a codon-dependent manner. [14C]tRNALys at the P site and Ac[3H]Lys-tRNALys at the A site of poly(A)-primed ribosomes were translocated to the E and P sites, respectively, by means of elongation factor G. The E site-bound [14C]tRNALys could be significantly chased by cognate tRNALys but not by non-cognate tRNAPhe, indicating the coded nature of the E site binding. Additional evidence is presented that the ribosome accommodates two adjacent codon-anticodon interactions at either A and P or P and E sites.

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Acylation Anticodon Binding Sites Binding, Competitive Codon Escherichia coli Peptide Elongation Factor G Peptide Elongation Factors Poly A Poly U RNA, Bacterial RNA, Messenger RNA, Transfer RNA, Transfer, Amino Acyl Ribosomes Journal Article

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H J Rheinberger, H Sternbach, K H Nierhaus. 1986-07-15. Codon-anticodon interaction at the ribosomal E site.. https://pubmed.ncbi.nlm.nih.gov/2424905/

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