Abstract
Radioactive trinucleotides and sRNA were chromatographed to-gether in an attempt to show reciprocal interaction between codon and anticodon in the absence of ribosomes. Radioactivity was found in those fractions that contained sRNA. Labelled mono- and dinucleotides, however, did not become associated with sRNA when both were submitted together to gel filtration. The trinucleotide AAG [adenine-adenine-guanine] could not be displaced from the sRNA by other trinucleotides. It is thought that a specific base pairing between trinucleotides and complementary positions on the transfer-RNA is responsible for this phenomenon.