1kuw
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Human islet amyloid polypeptide (hIAPP), or amylin, is a 37 amino acid | + | Human islet amyloid polypeptide (hIAPP), or amylin, is a 37 amino acid hormone secreted by pancreatic beta-cells. hIAPP constitutes approximately 90% of the amyloid deposits found in type II diabetic patients. It has been shown that the central region of the peptide (hIAPP(20-29)) constitutes the nucleation site for the amyloidogenic process with F23 playing a key role in the formation of the beta-pleated structures. In addition, it has been proposed that an important stage in the cytotoxicity of hIAPP is its interaction with the beta-cell membranes. As a first step toward the characterization of the interaction of hIAPP with cell membranes, we determined conformational preferences of hIAPP(20-29) in membrane-mimicking environments. We found that upon interacting with negatively charged micelles, the dominant conformation of hIAPP(20-29) is a distorted type I beta-turn centered on residues F23 and G24, with F23, A25, and I26 forming a small hydrophobic cluster that may facilitate the interaction of this peptide with the membrane bilayer. Moreover, we were able to elucidate the topological orientation of the peptide that is absorbed on the micelle surface, with the hydrophobic cluster oriented toward the hydrocarbon region of the micelles and both N- and C-termini exposed to the solvent. |
==About this Structure== | ==About this Structure== | ||
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[[Category: solution nmr]] | [[Category: solution nmr]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:38:08 2008'' |
Revision as of 11:38, 21 February 2008
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High-Resolution Structure and Localization of Amylin Nucleation Site in Detergent Micelles
Overview
Human islet amyloid polypeptide (hIAPP), or amylin, is a 37 amino acid hormone secreted by pancreatic beta-cells. hIAPP constitutes approximately 90% of the amyloid deposits found in type II diabetic patients. It has been shown that the central region of the peptide (hIAPP(20-29)) constitutes the nucleation site for the amyloidogenic process with F23 playing a key role in the formation of the beta-pleated structures. In addition, it has been proposed that an important stage in the cytotoxicity of hIAPP is its interaction with the beta-cell membranes. As a first step toward the characterization of the interaction of hIAPP with cell membranes, we determined conformational preferences of hIAPP(20-29) in membrane-mimicking environments. We found that upon interacting with negatively charged micelles, the dominant conformation of hIAPP(20-29) is a distorted type I beta-turn centered on residues F23 and G24, with F23, A25, and I26 forming a small hydrophobic cluster that may facilitate the interaction of this peptide with the membrane bilayer. Moreover, we were able to elucidate the topological orientation of the peptide that is absorbed on the micelle surface, with the hydrophobic cluster oriented toward the hydrocarbon region of the micelles and both N- and C-termini exposed to the solvent.
About this Structure
1KUW is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.
Reference
Conformational preferences of the amylin nucleation site in SDS micelles: an NMR study., Mascioni A, Porcelli F, Ilangovan U, Ramamoorthy A, Veglia G, Biopolymers. 2003 May;69(1):29-41. PMID:12717720
Page seeded by OCA on Thu Feb 21 13:38:08 2008
Categories: Single protein | Ilangovan, U. | Mascioni, A. | Porcelli, F. | Ramamoorthy, A. | Veglia, G. | Amylin | Hiapp | Micelles | Orientation | Solution nmr
