TopoisomeraseIIβ in HIV-1 transactivation
Anil Chekuri1, C Bhaskar1, V Satish Bollimpelli1
1Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
Archives of Biochemistry and Biophysics
|February 16, 2016
Summary
TopoisomeraseIIβ (TopoIIβ) promotes HIV-1 replication and transcription by interacting with Tat and the LTR region. Inhibiting TopoIIβ significantly impairs viral replication, highlighting its critical role in the HIV-1 life cycle.
Area of Science:
- Molecular Biology
- Virology
- Biochemistry
Background:
- TopoisomeraseIIβ (TopoIIβ) is a type II topoisomerase isoform implicated in viral infections.
- A potential role for TopoIIβ in the human immunodeficiency virus type 1 (HIV-1) life cycle has been suggested but not fully elucidated.
Purpose of the Study:
- To investigate the specific role of TopoIIβ in HIV-1 infection.
- To determine how TopoIIβ influences viral replication and transcription.
Main Methods:
- Gain and loss of function studies for TopoIIβ (overexpression and siRNA-mediated knockdown).
- Inhibition of TopoIIβ activity using ICRF-193 and merbarone.
- Co-immunoprecipitation and ChIP assays to assess protein-DNA interactions.
- Luciferase reporter assays to evaluate HIV-1 LTR transactivation.
Main Results:
- Overexpression of TopoIIβ enhanced HIV-1 replication and virion production.
- Downregulation or inhibition of TopoIIβ impaired HIV-1 replication.
- TopoIIβ interacts with HIV-1 Tat and is recruited to the long terminal repeat (LTR) region.
- TopoIIβ activity is crucial for HIV-1 LTR transactivation and viral gene expression.
Conclusions:
- TopoIIβ plays a significant role in regulating HIV-1 transcription and replication.
- TopoIIβ is involved in the recruitment of coactivator complexes to the HIV-1 LTR.
- Targeting TopoIIβ catalytic activity represents a potential strategy for controlling HIV-1 infection.
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