Isolation and structures of alligator gar (Lepisosteus spatula) insulin and pancreatic polypeptide.
Insulin and a 36-residue peptide with homology to pancreatic polypeptide (PP) were isolated from the endocrine pancreas of the alligator gar (Lepisosteus spatula), a ganoid fish, by gel filtration and HPLC. Heterologous radioimmunoassays were used to detect insulin-like and PP-like immunoreactivities during purification of the two peptides. The sequence of the 36-amino acid peptide containing a C-terminal tyrosinamide was identical at 31 of 36 positions to porcine neuropeptide Y (NPY). The amino acid sequence of this peptide is YPPKPENPGEDAPPEELAKYYSALRHYINLITRQRY-NH2. The second peptide, gar insulin, contains 52 amino acid residues and is composed of a 21-residue A chain and a 31-residue B chain. The sequence of the A chain is GIVEQCCHKPCTIYELENYCN. The sequence of the B chain is AANQHLCGSHLVEALYLVCGEKGFFYNPNKV.
Pollock
H G
HG
Veterans Administration Medical Center, Kansas City, Missouri 64128.
Kimmel
J R
JR
Hamilton
J W
JW
Rouse
J B
JB
Ebner
K E
KE
Lance
V
V
Rawitch
A B
AB
D000595:Amino Acid Sequence; D000818:Animals; D005399:Fishes / Q000502:physiology*; D007328:Insulin / Q000302:isolation & purification*; D007515:Islets of Langerhans / Q000032:analysis*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010191:Pancreatic Polypeptide / Q000302:isolation & purification*; D010446:Peptide Fragments / Q000032:analysis; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity
D007328:Insulin; D046911:Macromolecular Substances; D010446:Peptide Fragments; D010191:Pancreatic Polypeptide