Prosomatostatin-I is processed to somatostatin-26 and somatostatin-14 in the pancreas of the bowfin, Amia calva.
With the exception of the Agnatha (lampreys and hagfishes), somatostatin-14 is the predominant molecular form of somatostatin in the pancreas of species from all classes of vertebrates yet studied. The pancreas of the holostean fish, Amia calva (bowfin; order Amiiformes) contained somatostatin-like immunoreactivity that was resolved by reversed phase HPLC in two components. The primary structure of the more abundant peptide (somatostatin-26) was established as: Ser-Ala-Asn-Pro-Ala5-Leu-Ala-Pro-Arg-Glu10-Arg-Lys-Ala-Gly-+ ++Cys15-Lys-Asn-Phe- Phe-Trp20-Lys-Thr-Phe-Thr-Ser25-Cys. This amino acid sequence shows one substitution (Leu for Met at position 6) and two deletions compared with mammalian somatostatin-28. The minor component was identical to somatostatin-14. The data show that the pathway of post-translational processing of prosomatostatin-I in the bowfin pancreas is appreciably different from the corresponding pathway in teleost fish and higher vertebrates.
Wang
Y
Y
Regulatory Peptide Center, Creighton University Medical School, Omaha, NE 68178.
Youson
J H
JH
Conlon
J M
JM
D000595:Amino Acid Sequence; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005399:Fishes; D008297:Male; D008969:Molecular Sequence Data; D010179:Pancreas / Q000378:metabolism*; D011498:Protein Precursors / Q000302:isolation & purification / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D017386:Sequence Homology, Amino Acid; D013004:Somatostatin / Q000302:isolation & purification / Q000378:metabolism*
D011498:Protein Precursors; C083648:somatostatin 26; D013004:Somatostatin; C028456:prosomatostatin