PDBsum entry 1zka

Transcription

PDB id: 1zka

Contents

Protein chain

110 a.a. *

Waters ×62

* Residue conservation analysis

PDB id:

1zka

Name:

Transcription

Title:

Nf-kb relb forms an intertwined homodimer, y300s mutant

Structure:

Transcription factor relb. Chain: a. Fragment: dimerization domain. Engineered: yes. Mutation: yes

Source:

Mus musculus. House mouse. Organism_taxid: 10090. Gene: relb. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.

Biol. unit:

Dimer (from PDB file)

Resolution:

2.20Å R-factor: 0.206 R-free: 0.231

Authors:

D.B.Huang,D.Vu,G.Ghosh

Key ref:

D.B.Huang et al. (2005). NF-kappaB RelB forms an intertwined homodimer. Structure, 13, 1365-1373. PubMed id: 16154093 DOI: 10.1016/j.str.2005.06.018

Date:

02-May-05 Release date: 10-May-05

Protein chain

Q04863  (RELB_MOUSE) -  Transcription factor RelB from Mus musculus

Seq: 558 a.a.

Struc: 110 a.a.*

* PDB and UniProt seqs differ at 8 residue positions (black crosses)

DOI no: 10.1016/j.str.2005.06.018

Structure 13:1365-1373 (2005)

PubMed id: 16154093

NF-kappaB RelB forms an intertwined homodimer.

D.B.Huang, D.Vu, G.Ghosh.

ABSTRACT

The X-ray structure of the RelB dimerization domain (DD) reveals that the RelBDD assumes an unexpected intertwined fold topology atypical of other NF-kappaB dimers. All typical NF-kappaB dimers are formed by the association of two independently folded immunoglobulin (Ig) domains. In RelBDD, two polypeptides reconstruct both Ig domains in the dimer with an extra beta sheet connecting the two domains. Residues most critical to NF-kappaB dimer formation are invariant in RelB, and Y300 plays a positive role in RelBDD dimer formation. The presence of RelB-specific nonpolar residues at the surface removes several intradomain surface hydrogen bonds that may render the domain fold unstable. Intertwining may stabilize the RelBDD homodimer by forming the extra beta sheet. We show that, as in the crystal, RelB forms an intertwined homodimer in solution. We suggest that the transiently stable RelB homodimer might prevent its rapid degradation, allowing for heterodimer formation with p50 and p52.

Selected figure(s)

Figure 2.
Figure 2. Detailed Structural Comparisons between the RelBDD Homodimer and the p50DD Homodimer
(A) Overlay of the "b"-"e" b sheets from p50DD and RelBDD . This view is generated by rotating the superimposed Ig-like folds (right) 90° around the long axis of the fold, as shown in Figure 1E. All of the p50 (green) residues are involved in the dimer interface. RelB is shown in red and gray, respectively, for the two chains in the b sheet.
(B and C) Comparison of the orientations of homologous Tyr at the subunit interfaces of the RelBDD and p50DD dimers, respectively.
(D) The b turn connecting b strands "c'" and "e" and the residues present in the turn of p50DD are shown.
(E) The same segment as in (C) in RelBDD is shown. The turn is converted into a strand ("d"), and the two opposing strands connecting the two Ig-like folds of RelBDD are presented. The side chain conformations of His and Gln are completely different in the two dimers.
(F) The hydrogen bonding pattern in the swapped region of the MLAM mutant of p50DD.

The above figure is reprinted by permission from Cell Press: Structure (2005, 13, 1365-1373) copyright 2005.

Figure was selected by an automated process.