Evidence for the presence of a secondary structure at the dibasic processing site of prohormone: the pro-ocytocin model
Details
Serval ID
serval:BIB_7BA03C0A3E58
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Evidence for the presence of a secondary structure at the dibasic processing site of prohormone: the pro-ocytocin model
Journal
EMBO Journal
ISSN
0261-4189 (Print)
Publication state
Published
Issued date
07/1992
Volume
11
Number
7
Pages
2399-405
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Jul
Research Support, Non-U.S. Gov't --- Old month value: Jul
Abstract
Bioactivation of pro-proteins by limited proteolysis is a general mechanism in the biosynthesis of hormones, receptors and viral protein precursors. This proceeds by cleavage of peptide bonds at the level of single or pairs of basic residues in the proforms. Examination of a number of cleavage loci in various precursors failed to reveal any consensus primary sequence around the dibasic cleavage sites. Thus it has been proposed, on the basis of secondary structure predictions [Rholam, M., Nicolas, P. and Cohen, P. (1986) FEBS Lett., 207, 1-6], that those basic residues which operate as signal loci for the proteolytic enzyme machinery are situated in, or next to, privileged precursor regions most often constituted by flexible and exposed motifs, e.g. beta-turns and/or loops. Peptides reproducing the N-terminal processing domain of the hormone precursor, pro-ocytocin-neurophysin, were examined by a combination of spectroscopical techniques including circular dichroism, infrared Fourier transform and one- and two-dimensional proton NMR. The results indicate that: (i) the region situated on the N terminus of the Lys-Arg doublet is organized as a beta-turn in solution; (ii) the sequential organization of the residues participating in the beta-turn determines the privileged relative orientation of the basic amino acid side chains and the subtype of turn; (iii) the peptide segment situated on the C-terminal side of the dibasic, corresponding to the N-terminal octapeptide of neurophysin, is organized as an alpha-helix.(ABSTRACT TRUNCATED AT 250 WORDS)
Keywords
Amino Acid Sequence
Animals
Cattle
Circular Dichroism
Endopeptidases/metabolism
Fourier Analysis
Kinetics
Magnetic Resonance Spectroscopy
Molecular Sequence Data
Oxytocin/*chemistry/metabolism
Peptides/chemical synthesis/metabolism
Protein Conformation
Protein Precursors/*chemistry/metabolism
*Protein Processing, Post-Translational
Spectrophotometry, Infrared
Pubmed
Web of science
Create date
28/01/2008 11:34
Last modification date
20/08/2019 15:37