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there are two examples of adjacent messages with overlapping termination and initiation codons; these are trpE-trpD and trpB-trpA cistron pairs, both with the intercistronic region UGAUG (Oppenheim & Yanofsky, 1980; Platt & Yanofsky, 1975). Correspondingly, the translational coupling is tight and ensures equimolar production of polypeptides that are constituents of one enzyme complex (Das & Yanofsky, 1984).

In the translationally coupled cistrons VII and IX of the bacteriophage f1 RNA the termination codon UGA of VII overlaps the initiation codon AUG of IX by two nucleotides, and the latter is shifted upstream relative to the termination codon (Ivey-Hoyle & Steege, 1989):

In the polycistronic message transcribed from galactose operon, galE-galT-galK, the termination and initiation codons in the galT-galK pair are separated by three nucleotides, with the Shine-Dalgarno sequence upstream of the termination codon:

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