Complete amino acid sequence of porcine adrenomedullin and cloning of cDNA encoding its precursor.

Porcine adrenomedullin was isolated from adrenal medulla extract and its amino acid sequence was determined. The peptide is identical to human adrenomedullin with a single replacement of Gly for Asn at position 40. The cDNA clone encoding the porcine adrenomedullin precursor was isolated and sequenced. The precursor for adrenomedullin (preproadrenomedullin) is 188 amino acids in length, including the adrenomedullin sequence, followed by a glycine (the amide donor). In addition to adrenomedullin, proadrenomedullin (proAM) contains a candidate for a unique 20-residue peptide, proAM-N20, whose carboxy-terminus may be amidated. By RNA blot analysis, porcine adrenomedullin mRNA was found to be highly expressed in several porcine tissues including lung and kidney as well as adrenal medulla.