Related Experiment Video
Updated: May 21, 2026
06:18
Imaging of Podocytic Proteins Nephrin, Actin, and Podocin with Expansion Microscopy
Published on: April 23, 2021
Nef interaction with actin compromises human podocyte actin cytoskeletal integrity
Raymond Tan1, Hitesh Patni, Pranai Tandon
1Department of Immunology, Feinstein Institute for Medical Research, North Shore LIJ Health System, NY, USA.
Experimental and Molecular Pathology
|June 23, 2012
Summary
The HIV-1 Nef protein alters podocyte structure and function by interacting with actin, leading to cytoskeletal changes and impaired cell adhesion in HIV-associated nephropathy.
Area of Science:
- Nephrology
- Molecular Biology
- Virology
Background:
- HIV-1 associated nephropathy involves podocyte injury.
- The HIV-1 accessory protein Nef is implicated in podocyte phenotype changes.
Purpose of the Study:
- To investigate how Nef alters podocyte structure and function.
- To identify proteins interacting with Nef in podocytes.
Main Methods:
- GST pull-down and yeast two-hybrid assays to identify Nef-interacting proteins.
- Co-localization studies to confirm interactions and assess cytoskeletal changes.
- Microarray analysis to evaluate gene expression changes.
- Functional assays for cell attachment and detachment.
Main Results:
- Nef interacts with actin, syntrophin, filamin B, syntaxin, translational elongation factor 1, and zyxin.
- Nef disrupts actin cytoskeleton, reducing stress fibers and increasing filopodia/lamellipodia.
- Nef alters expression of key regulatory genes (Rac1, CDC42) and reduces ASMase activity.
- Nef-expressing podocytes show impaired attachment and enhanced detachment.
Conclusions:
- Nef interaction with actin compromises podocyte cytoskeleton integrity.
- Nef-induced cytoskeletal changes contribute to podocyte dysfunction in HIV-1 nephropathy.
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