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A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses
Published on: August 31, 2014
Long-range recombination gradient between HIV-1 subtypes B and C variants caused by sequence differences in the
Mario P S Chin1, Sook-Kyung Lee, Jianbo Chen
1HIV Drug Resistance Program, National Cancer Institute, Frederick, MD 21702, USA.
Journal of Molecular Biology
|March 4, 2008
Summary
Matching dimerization initiation signals (DIS) in HIV-1 subtypes B and C corrects the recombination gradient. This finding reveals key molecular mechanisms generating inter-subtype HIV-1 recombinants crucial to the AIDS pandemic.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- Human Immunodeficiency Virus type 1 (HIV-1) intersubtype recombinants significantly influence the AIDS pandemic.
- Understanding the molecular mechanisms of HIV-1 intersubtype recombination is critical for controlling viral evolution.
Purpose of the Study:
- To investigate the molecular mechanisms underlying the generation of HIV-1 intersubtype recombinants.
- To determine the role of the dimerization initiation signal (DIS) in HIV-1 recombination frequency and distribution.
Main Methods:
- Analysis of crossover junctions in HIV-1 subtypes B and C proviral genomes.
- Comparison of recombination patterns between natural B/C recombinants and those generated with a modified subtype B virus (carrying a subtype C DIS).
Main Results:
- A recombination gradient was observed in natural B/C recombinants, with more crossover junctions in the 3' half of the analyzed genome.
- Matching the DIS between subtypes B and C significantly increased the frequency of recombination events.
- Even distribution of crossover junctions was observed when DIS sequences were matched, correcting the 5' bias.
Conclusions:
- Base-pairing at the DIS is essential for maintaining nucleic acid structure during HIV-1 reverse transcription.
- DIS sequence complementarity plays a crucial role in regulating the frequency and genomic distribution of HIV-1 intersubtype recombination.
- These findings provide critical insights into the generation of diverse HIV-1 strains driving the AIDS epidemic.
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