Goldfish gamma-preprotachykinin mRNA encodes the neuropeptides substance P, carassin, and neurokinin A.

Two cDNAs, size 969 bp and 1146 bp respectively, encoding goldfish gamma-preprotachykinin (gamma-PPT) were identified. Both cDNAs contain the same 345 bp open reading frame. The deduced 114-amino acid gamma-PPT contains the sequence of substance P, carassin and neurokinin A. sequence analysis of the two cDNA 5'-untranslated regions shows that the two cDNAs may represent different PPT-A gene transcripts resulting from the alternative transcriptional start sites. Expression of gamma-PPT mRNA was detected in a wide range of brain areas from the olfactory bulbs to the posterior brain region, as well as in the intestine, testis and pituitary.