3GUT

Crystal structure of a higher-order complex of p50:RelA bound to the HIV-1 LTR

DOI: 10.2210/pdb3GUT/pdb
NDB: PD1275

Classification: TRANSCRIPTION/DNA
Organism(s): Homo sapiens, Human immunodeficiency virus
Mutation(s): No

Deposited: 2009-03-30 Released: 2009-09-08
Deposition Author(s): Stroud, J.C., Oltman, A.J., Han, A., Bates, D.L., Chen, L.

Experimental Data Snapshot

Method: X-RAY DIFFRACTION
Resolution: 3.59 Å
R-Value Free: 0.301
R-Value Work: 0.245

wwPDB Validation 3D Report Full Report

This is version 1.2 of the entry. See complete history.

Literature

Structural basis of HIV-1 activation by NF-kappaB--a higher-order complex of p50:RelA bound to the HIV-1 LTR.

Stroud, J.C., Oltman, A., Han, A., Bates, D.L., Chen, L.

(2009) J Mol Biol 393: 98-112

PubMed: 19683540 Search on PubMedSearch on PubMed Central
DOI: 10.1016/j.jmb.2009.08.023
Primary Citation of Related Structures:
3GUT

PubMed Abstract:

The activation and latency of human immunodeficiency virus type 1 (HIV-1) are tightly controlled by the transcriptional activity of its long terminal repeat (LTR) region. The LTR is regulated by viral proteins as well as host factors, including the nuclear factor kappaB (NF-kappaB) that becomes activated in virus-infected cells. The two tandem NF-kappaB sites of the LTR are among the most highly conserved sequence elements of the HIV-1 genome. Puzzlingly, these sites are arranged in a manner that seems to preclude simultaneous binding of both sites by NF-kappaB, although previous biochemical work suggests otherwise. Here, we have determined the crystal structure of p50:RelA bound to the tandem kappaB element of the HIV-1 LTR as a dimeric dimer, providing direct structural evidence that NF-kappaB can occupy both sites simultaneously. The two p50:RelA dimers bind the adjacent kappaB sites and interact through a protein contact that is accommodated by DNA bending. The two dimers clamp DNA from opposite faces of the double helix and form a topological trap of the bound DNA. Consistent with these structural features, our biochemical analyses indicate that p50:RelA binds the HIV-1 LTR tandem kappaB sites with an apparent anti-cooperativity but enhanced kinetic stability. The slow on and off rates we observe may be relevant to viral latency because viral activation requires sustained NF-kappaB activation. Furthermore, our work demonstrates that the specific arrangement of the two kappaB sites on the HIV-1 LTR can modulate the assembly kinetics of the higher-order NF-kappaB complex on the viral promoter. This phenomenon is unlikely restricted to the HIV-1 LTR but probably represents a general mechanism for the function of composite DNA elements in transcription.

Organizational Affiliation:

Molecular and Computational Biology, Department of Biological Sciences, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089-2910, USA.

Macromolecules

Find similar proteins by:

(by identity cutoff) | Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Transcription factor p65	A, C, E, G	273	Homo sapiens	Mutation(s): 0 Gene Names: RELA, NFKB3
Find proteins for Q04206 (Homo sapiens) Explore Q04206 Go to UniProtKB: Q04206
NIH Common Fund Data Resources
PHAROS: Q04206 GTEx: ENSG00000173039
Protein Feature View Expand
Reference Sequence

Find similar proteins by:

(by identity cutoff) | Structure

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Nuclear factor NF-kappa-B p105 subunit	B, D, F, H	312	Homo sapiens	Mutation(s): 0 Gene Names: NFKB1
Find proteins for P19838 (Homo sapiens) Explore P19838 Go to UniProtKB: P19838
NIH Common Fund Data Resources
PHAROS: P19838 GTEx: ENSG00000109320
Protein Feature View Expand
Reference Sequence