PDBsum entry 1g7d

Chaperone

PDB id: 1g7d

Contents

Protein chain

106 a.a. *

* Residue conservation analysis

PDB id:

1g7d

Name:

Chaperone

Title:

Nmr structure of erp29 c-domain

Structure:

Endoplasmic reticulum protein erp29. Chain: a. Fragment: c-terminal domain. Engineered: yes

Source:

Rattus norvegicus. Norway rat. Organism_taxid: 10116. Expressed in: escherichia coli. Expression_system_taxid: 562.

NMR struc:

20 models

Authors:

E.Liepinsh,S.Mkrtchian,M.Barishev,A.Sharipo,M.Ingelman-Sundberg, G.Otting

Key ref:

E.Liepinsh et al. (2001). Thioredoxin fold as homodimerization module in the putative chaperone ERp29: NMR structures of the domains and experimental model of the 51 kDa dimer. Structure, 9, 457-471. PubMed id: 11435111 DOI: 10.1016/S0969-2126(01)00607-4

Date:

10-Nov-00 Release date: 29-Nov-00

Protein chain

P52555  (ERP29_RAT) -  Endoplasmic reticulum resident protein 29 from Rattus norvegicus

Seq: 260 a.a.

Struc: 106 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1016/S0969-2126(01)00607-4

Structure 9:457-471 (2001)

PubMed id: 11435111

Thioredoxin fold as homodimerization module in the putative chaperone ERp29: NMR structures of the domains and experimental model of the 51 kDa dimer.

E.Liepinsh, M.Baryshev, A.Sharipo, M.Ingelman-Sundberg, G.Otting, S.Mkrtchian.

ABSTRACT

BACKGROUND: ERp29 is a ubiquitously expressed rat endoplasmic reticulum (ER) protein conserved in mammalian species. Fold predictions suggest the presence of a thioredoxin-like domain homologous to the a domain of human protein disulfide isomerase (PDI) and a helical domain similar to the C-terminal domain of P5-like PDIs. As ERp29 lacks the double-cysteine motif essential for PDI redox activity, it is suggested to play a role in protein maturation and/or secretion related to the chaperone function of PDI. ERp29 self-associates into 51 kDa dimers and also higher oligomers. RESULTS: 3D structures of the N- and C-terminal domains determined by NMR spectroscopy confirmed the thioredoxin fold for the N-terminal domain and yielded a novel all-helical fold for the C-terminal domain. Studies of the full-length protein revealed a short, flexible linker between the two domains, homodimerization by the N-terminal domain, and the presence of interaction sites for the formation of higher molecular weight oligomers. A gadolinium-based relaxation agent is shown to present a sensitive tool for the identification of macromolecular interfaces by NMR. CONCLUSIONS: ERp29 is the first eukaryotic PDI-related protein for which the structures of all domains have been determined. Furthermore, an experimental model of the full-length protein and its association states was established. It is the first example of a protein where the thioredoxin fold was found to act as a specific homodimerization module, without covalent linkages or supporting interactions by further domains. A homodimerization module similar as in ERp29 may also be present in homodimeric human PDI.

Selected figure(s)

Figure 6.
Figure 6. Different Stereorepresentations of Residues 155-256 of the NMR Solution Structure of the C-Terminal Domain of ERp29All three representations show the structure in the same orientation as in Figure 2. (a) Backbone trace of the conformer with the lowest energy after restrained energy minimization. (b) Ensemble of 20 conformers, using the backbone atoms of residues 160-250 for superposition. (c) Heavy-atom display of the conformer of (a). The same color code was used as in Figure 4

The above figure is reprinted by permission from Cell Press: Structure (2001, 9, 457-471) copyright 2001.

Figure was selected by an automated process.