A processing enzyme cleaving avian progastrin at post-Phe bonds
Research output: Contribution to journal › Journal article › Research › peer-review
Neuroendocrine peptides mature partly through endoproteolytic processing of long precursor forms. Best characterised is cleavage at mono- and dibasic residues, but additional sites also exist. Among these is post-Phe cleavage, first suggested to participate in the processing of chicken progastrin. In order to characterise this new mechanism, antibodies recognising the processing products of post-Phe cleavage of chicken progastrin were produced for radioimmunoassay measurements and immunocytochemistry. High concentrations of the carboxyamidated C-terminus and the N-terminus of gastrin-53 were measured in extracts of the antrum. In addition, significant amounts were detected using an assay specific for the N-terminus of gastrin-30 and with another assay for the C-terminus of the corresponding peptide, gastrin-53(1-23), obtained after cleavage at the Phe(23)-Ala(24) bond of gastrin-53. Colocalisation in antral G-cells of the N-termini of gastrin-53 and gastrin-30 and of the C-terminus of gastrin-53(1-23) was confirmed by immunohistochemistry. Finally, we identified the intact N-terminal 1-23 fragment of gastrin-53 complementary to gastrin-30, verifying endoproteolytic cleavage at the Phe(23)-Ala(24) bond. Taken together, the results support the existence of vertebrate endoprotease cleaving hormone precursors at post-Phe sites.
Original language | English |
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Journal | B B A - Reviews on Cancer |
Volume | 1547 |
Issue number | 1 |
Pages (from-to) | 64-71 |
Number of pages | 8 |
ISSN | 0006-3002 |
Publication status | Published - 5 May 2001 |
- Amino Acid Sequence, Animals, Antibodies/immunology, Binding Sites, Chickens, Chromatography, Gel, Digestive System/metabolism, Epitopes/immunology, Fluorescent Antibody Technique, Gastric Mucosa/metabolism, Gastrins/chemistry, Molecular Sequence Data, Peptides/chemical synthesis, Protein Precursors/chemistry, Pyloric Antrum/metabolism, Radioimmunoassay, Tissue Extracts/chemistry
Research areas
ID: 194815021