Is there a relationship between DNA sequences encoding peptide ligands and their receptors?
It has been suggested that the coding for a ligand and its receptor may have originated in inverse complementary strands of the same DNA. This would imply a deficiency of stop codons in the complementary strand of the ligand message sequence. We have sought evidence of such deficiencies by an analysis of the usage of selected codons in 23 human neuropeptide and hormone mRNA sequences. We have also searched directly for similarities between substance K or substance P and the substance K receptor. Although bovine proopiomelanocortin has an open reading frame for the full extent of the inverse complement of the coding region, this seems to be a unique case. The data as a whole do not support the hypothesis.
