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Updated: Sep 20, 2026

Assessment of Immunologically Relevant Dynamic Tertiary Structural Features of the HIV-1 V3 Loop Crown R2 Sequence by ab initio Folding
10:50

Assessment of Immunologically Relevant Dynamic Tertiary Structural Features of the HIV-1 V3 Loop Crown R2 Sequence by ab initio Folding

Published on: September 15, 2010

Is the V3 loop involved in HIV binding to CD4?

Monica Dettin1, Pasquale Ferranti, Claudia Scarinci

  • 1Department of Chemical Process Engineering, University of Padova, 35131-Padova, Italy. monica.dettin@unipd.it

Biochemistry
|July 30, 2003
PubMed

Insights

Researchers identified a specific interaction between HIV-MN-gp120 V3 loop and the CD4 Ig-CDR3-like region. This finding advances understanding of HIV entry and aids in developing new antiviral therapies.

Area of Science:

  • Virology
  • Immunology
  • Structural Biology

Background:

  • Human immunodeficiency virus (HIV) entry into host cells depends on interactions between the viral envelope glycoprotein gp120 and cellular receptors CD4 and chemokine receptors.
  • The gp120 binding site on CD4 has been localized to the Ig-CDR2-like region of the CD4 first domain.
  • A second region, the Ig-CDR3-like region of CD4, is implicated in gp120-CD4 interactions, but the corresponding gp120 binding partner was previously unidentified.

Purpose of the Study:

  • To identify the specific region on the HIV-MN-gp120 V3 loop that interacts with the CD4 Ig-CDR3-like region.
  • To elucidate the molecular mechanisms underlying HIV-1 entry and cell penetration.

Main Methods:

  • Photoaffinity labeling experiments were employed to investigate molecular interactions.
  • Peptide mapping of the HIV-MN-gp120 V3 loop, specifically the (307-330)m region, was performed.

Main Results:

  • A peptide corresponding to the (307-330)m region of the HIV-MN-gp120 V3 loop was found to bind to a specific sequence within the CD4 Ig-CDR3-like region.
  • This interaction provides the missing link between the gp120 V3 loop and the CD4 receptor.

Conclusions:

  • The study successfully identified a critical binding interaction between a V3 loop peptide of HIV-MN-gp120 and the CD4 Ig-CDR3-like region.
  • These findings enhance the understanding of the complex HIV-1 entry pathway.
  • The identified interaction may serve as a target for the development of novel therapeutic agents against HIV infection.

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