Vasoactive intestinal polypeptide (VIP) was isolated in two molecular forms from an extract of the gastroenteropancreatic system of the pallid sturgeon Scaphirhynchus albus (Acipenseriformes). VIP-1 was identical to the peptide previously isolated from the rainbow trout Oncorhynchus mykiss and the bowfin, Amia calva, consistent with the proposed sister group relationship of the Acipenseriformes and the Neopterygii. Sturgeon VIP-2 contained the amino acid substitution (Ala4 → Ser) at a site previously regarded as invariant. The isolation of two distinct VIP gene products provides some support for the hypothesis that S. albus, with approximately 120 chromosomes, is functionally tetraploid but the alternative view that the species is functionally diploid and the two peptides arose from a local duplication of the VIP gene within the Scaphirhynchus lineage cannot be rejected.
|Number of pages||8|
|Journal||Fish Physiology and Biochemistry|
|Publication status||Published - Dec 2001|
- T etraploidization
ASJC Scopus subject areas
- Aquatic Science