Related Experiment Video
Updated: Jun 23, 2025
13:07
Determining 3'-Termini and Sequences of Nascent Single-Stranded Viral DNA Molecules during HIV-1 Reverse Transcription in Infected Cells
Published on: January 30, 2019
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Retroviral PBS-segment sequence and structure: Orchestrating early and late replication events
Xiao Heng1, Amanda Paz Herrera2, Zhenwei Song3
1Department of Biochemistry, University of Missouri, Columbia, MO, 65211, USA. hengx@health.missouri.edu.
Retrovirology
|June 17, 2024
Summary
The HIV-1 5' untranslated region (UTR) PBS-segment forms a complex structure that interacts with host factors like RNA helicase A (RHA). This interaction is crucial for viral replication, RNA modification, and biphasic protein translation, offering potential therapeutic targets.
Area of Science:
- Retroviral RNA biology
- Molecular virology
- Structural biology
Background:
- The 5' untranslated region (UTR) of retroviruses contains essential cis-acting elements for replication.
- The primer binding site (PBS) segment is critical for reverse transcription and viral protein expression.
- HIV-1 RNA biology involves intricate interactions between viral elements and host factors.
Purpose of the Study:
- To elucidate the structural and functional role of the HIV-1 PBS-segment in viral replication.
- To understand the interaction between the PBS-segment and host RNA binding proteins.
- To explore the implications for viral infectivity and therapeutic targeting.
Main Methods:
- Genetic mapping
- Cofactor affinity experiments
- Nuclear Magnetic Resonance (NMR) spectroscopy
- Small-angle X-ray scattering (SAXS)
Main Results:
- The HIV-1 PBS-segment folds into a three-way junction structure.
- This structure is recognized by the host nuclear RNA helicase A (RHA).
- RHA facilitates m7-guanosine Cap hypermethylation, enhancing virion infectivity and enabling biphasic translation.
Conclusions:
- Host adaptation and RNA shapeshifting are fundamental to PBS-segment function in retroviral replication.
- The PBS-segment orchestrates both RNA reverse transcription and nuclear RNA modification for viral protein translation.
- Understanding the PBS-segment-host protein interactions may reveal novel therapeutic targets against retroviruses.
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