Bimodal high-affinity association of Brd4 with murine leukemia virus integrase and mononucleosomes

The importance of understanding the molecular mechanisms of murine leukemia virus (MLV) integration into host chromatin is highlighted by the development of MLV-based vectors for human gene-therapy. We have recently identified BET proteins (Brd2, 3 and 4) as the main cellular binding partners of MLV...

Full description

Saved in:
Bibliographic Details
Published in:Nucleic acids research 2014-04, Vol.42 (8), p.4868-4881
Main Authors: Larue, Ross C., Plumb, Matthew R., Crowe, Brandon L., Shkriabai, Nikoloz, Sharma, Amit, DiFiore, Julia, Malani, Nirav, Aiyer, Sriram S., Roth, Monica J., Bushman, Frederic D., Foster, Mark P., Kvaratskhelia, Mamuka
Format: Article
Language:English
Subjects:
Cell Cycle Proteins
DNA - metabolism
Gene Regulation, Chromatin and Epigenetics
HEK293 Cells
Histones - metabolism
Humans
Integrases - chemistry
Integrases - metabolism
Leukemia Virus, Murine - enzymology
Leukemia Virus, Murine - physiology
Murine leukemia virus
Nuclear Proteins - metabolism
Nucleosomes - metabolism
Protein Binding
Protein Interaction Domains and Motifs
Transcription Factors - metabolism
Virus Integration
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The importance of understanding the molecular mechanisms of murine leukemia virus (MLV) integration into host chromatin is highlighted by the development of MLV-based vectors for human gene-therapy. We have recently identified BET proteins (Brd2, 3 and 4) as the main cellular binding partners of MLV integrase (IN) and demonstrated their significance for effective MLV integration at transcription start sites. Here we show that recombinant Brd4, a representative of the three BET proteins, establishes complementary high-affinity interactions with MLV IN and mononucleosomes (MNs). Brd4(1–720) but not its N- or C-terminal fragments effectively stimulate MLV IN strand transfer activities in vitro. Mass spectrometry- and NMR-based approaches have enabled us to map key interacting interfaces between the C-terminal domain of BRD4 and the C-terminal tail of MLV IN. Additionally, the N-terminal fragment of Brd4 binds to both DNA and acetylated histone peptides, allowing it to bind tightly to MNs. Comparative analyses of the distributions of various histone marks along chromatin revealed significant positive correlations between H3- and H4-acetylated histones, BET protein-binding sites and MLV-integration sites. Our findings reveal a bimodal mechanism for BET protein-mediated MLV integration into select chromatin locations.
ISSN:0305-1048
1362-4962
DOI:10.1093/nar/gku135