Structural requirements of pancreatic polypeptide receptor binding
| Autor: | Jones O. Akpan, Katherine M. Leith, Ronald L. Gingerich, Jules A. Hoffmann, R. E. Chance, William R. Gilbert |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
medicine.medical_specialty
Physiology Endocrinology Diabetes and Metabolism Molecular Sequence Data Pancreatic Polypeptide Binding Competitive Receptors Gastrointestinal Hormone Residue (chemistry) chemistry.chemical_compound Dogs Intestinal mucosa Physiology (medical) Internal medicine Intestine Small medicine Animals Pancreatic polypeptide Amino Acid Sequence Intestinal Mucosa Tyrosine Receptor Peptide sequence Base Sequence Methionine sulfoxide Cell Membrane Protein primary structure Kinetics Endocrinology Biochemistry chemistry |
| Zdroj: | American Journal of Physiology-Endocrinology and Metabolism. 261:E319-E324 |
| ISSN: | 1522-1555 0193-1849 |
| DOI: | 10.1152/ajpendo.1991.261.3.e319 |
| Popis: | Pancreatic polypeptide (PP) receptors have been identified and characterized on the basolateral membranes (BLM) of canine intestinal mucosa. The present study was designed to ascertain the structural requirements of the PP molecule for binding to its receptor. A radioreceptor assay using purified BLM was employed to elucidate receptors specific to PPs of various mammalian species and to modified bovine PP (bPP) fragments. Receptor cross-reactivities (CR) to various PPs and bPP fragments were established. Results show that percent receptor CR by PPs of various species was as follows: bPP (100%) greater than human PP (68%) greater than porcine PP (50%) greater than canine PP (45%) greater than ovine PP (36%) greater than rat PP (3%). The fragments bPP-(1-15), bPP-(1-17), bPP-(1-26), bPP-(16-23), bPP-(18-30), bPP-(24-36), bPP-(27-35), and bPP-(31-36) at 500 nM did not significantly displace tracer from receptor (less than 0.1% CR). Des-COOH-terminal tyrosinamide [bPP-(1-35)] produced less than 0.1% CR. Oxidation of bPP methionine-30 residue to methionine sulfoxide decreased displacement to 67%. Modification of native amidated tyrosinamide to the free acid abolished receptor binding, whereas esterification to the methyl ester of COOH-terminal tyrosine restored binding to 60%. Additionally, percent CR decreased progressively as amino acid residues were deleted from the NH2-terminal region. We conclude that the molecular homologue of PP primary structure is necessary for full receptor binding. Both the NH2- and COOH-terminal residues are required for recognition, and the COOH-terminal tyrosinamide must be intact for PP binding to its receptor. |
| Databáze: | OpenAIRE |
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