Stable complex formation between HIV Rev and the nucleosome assembly protein, NAP1, affects Rev function.

Area of Science:

• Molecular Biology
• Virology
• Cell Biology

Background:

• The Rev protein of Human Immunodeficiency Virus type 1 (HIV-1) is critical for viral replication.
• Rev facilitates the nuclear export of unspliced and partially spliced viral RNAs, a key step in the HIV-1 life cycle.
• Understanding Rev's interactions is crucial for developing antiviral strategies.

Purpose of the Study:

• To identify cellular proteins that interact with the HIV-1 Rev protein.
• To elucidate the functional consequences of the interaction between Rev and identified proteins on Rev's nuclear export function.

Main Methods:

• Modified tandem affinity purification (TAP) tagging was employed to identify Rev-interacting proteins in human cells.
• Rev affinity chromatography was used to confirm the interaction between Rev and nucleosome assembly protein 1 (Nap1).
• In vitro assays were performed to assess Nap1's effect on Rev oligomerization and RNA binding.

Main Results:

• A significant interaction was discovered between HIV-1 Rev and nucleosome assembly protein 1 (Nap1).
• Nap1 binds to the arginine-rich domain of Rev and influences its oligomerization state in vitro.
• Nap1 overexpression enhanced Rev-mediated RNA export, decreased Rev's nucleolar localization, and altered its nuclear import rates.

Conclusions:

• Nucleosome assembly protein 1 (Nap1) is a novel interacting partner of HIV-1 Rev.
• Nap1 positively regulates the nuclear export function of Rev, likely by increasing Rev's availability.
• This interaction represents a potential target for therapeutic intervention against HIV-1.