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Updated: Jul 20, 2026
11:31
Crystal Structure of the N-terminal Domain of Ryanodine Receptor from Plutella xylostella
Published on: November 30, 2018
NMR structure of the calreticulin P-domain
L Ellgaard1, R Riek, T Herrmann
1Institut für Biochemie, Eidgenössische Technische Hochschule, Universitätstrasse 16, CH-8092 Zurich, Switzerland.
Summary
The NMR structure of rat calreticulin P-domain reveals a unique hairpin fold stabilized by beta-sheets and hydrophobic clusters. This finding offers new insights into the function of this endoplasmic reticulum chaperone.
Area of Science:
- Biochemistry
- Structural Biology
- Molecular Biology
Background:
- Calreticulin is an abundant endoplasmic reticulum chaperone protein.
- Understanding the structure of calreticulin's P-domain is crucial for elucidating its function.
Purpose of the Study:
- To determine the Nuclear Magnetic Resonance (NMR) structure of the rat calreticulin P-domain (CRT(189-288)).
- To provide a structural basis for functional studies of calreticulin.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy was used to determine the 3D structure.
- Analysis of secondary structure elements (beta-sheets) and hydrophobic interactions.
Main Results:
- The P-domain adopts a globally extended hairpin fold involving the entire polypeptide chain.
- Three antiparallel beta-sheets stabilize the structure, with conserved tryptophyl residues in hydrophobic clusters.
- The structure comprises two well-ordered subdomains separated by a disordered linker region.
Conclusions:
- The determined NMR structure of CRT(189-288) reveals a novel fold with repeating interaction patterns.
- This structural information serves as a foundation for future functional investigations of calreticulin.
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