The somatostatin-28(1-12)-NPAMAP sequence: an essential helical-promoting motif governing prosomatostatin processing at mono- and dibasic sites

Détails

ID Serval
serval:BIB_5BCD7851AAFB
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
The somatostatin-28(1-12)-NPAMAP sequence: an essential helical-promoting motif governing prosomatostatin processing at mono- and dibasic sites
Périodique
Biochemistry
Auteur(s)
Brakch  N., Lazar  N., Panchal  M., Allemandou  F., Boileau  G., Cohen  P., Rholam  M.
ISSN
0006-2960 (Print)
Statut éditorial
Publié
Date de publication
02/2002
Volume
41
Numéro
5
Pages
1630-9
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Feb 5
Résumé
Proline residues, known to have special structural properties, induce particular conformations which participate in some biological functions. Two prolines (Pro(-9), Pro(-5)) located near the processing sites (Arg(-15) and Arg(-2)Lys(-)(1)) of human prosomatostatin were previously shown to be important for cleavage of the precursor into somatostatin-28 (S-28) and somatostatin-14 (S-14) [Gomez et al. (1989) EMBO J. 8, 2911-2916]. In this study, the importance of the pentapeptide P-A-M-A-P sequence (P-(X)(3)-P pattern), located in the S-28(1-12) segment connecting the mono- and dibasic cleavage sites, was investigated by using site-directed mutagenesis. Analysis of prosomatostatin-derived peptides produced by expression of mutated cDNA species in Neuro2A cells indicated that (i) deletion of PAMAP decreased S-14 production, (ii) deletion of the two Pro residues almost abolished the cleavage at the dibasic site, and (iii) Pro displacement generating the AMAPP motif resulted in a decrease of S-28 production. Moreover, both theoretical and spectroscopic studies of synthetic peptides reproducing the S-28(1-12) sequence bearing critical mutations showed that this sequence can organize as an alpha helical structure. These observations demonstrate that NPAMAP constitutes an accurate alpha-helix nucleation motif allowing for the generation of equal amounts of S-28 and S-14 from their common precursor in Neuro2A cells. Moreover, they emphasize the importance of the S-28(1-12) segment joining Arg(-15) and Arg(-2)Lys(-1) cleavage sites whose conformational organization is essential for controlling their accessibility to the appropriate processing proteases.
Mots-clé
Amino Acid Motifs/genetics Amino Acid Sequence Amino Acid Substitution/genetics Animals Arginine/metabolism Circular Dichroism Fishes Humans Hydrolysis Lysine/metabolism Mice Molecular Sequence Data Mutagenesis, Site-Directed Oligopeptides/*chemistry/genetics/*metabolism Protein Conformation Protein Precursors/*chemistry/genetics/*metabolism *Protein Processing, Post-Translational/genetics Protein Structure, Secondary/genetics Protein Structure, Tertiary/genetics Sequence Deletion Somatostatin/*chemistry/genetics/*metabolism Somatostatin-28 Spectroscopy, Fourier Transform Infrared Tumor Cells, Cultured
Pubmed
Web of science
Création de la notice
28/01/2008 10:35
Dernière modification de la notice
20/08/2019 14:14
Données d'usage