Báo cáo khóa học: Mechanisms of internalization and recycling of the chemokine receptor, CCR5

Mechanisms of Internalization and Recycling of the Chemokine Receptor, CCR5

Authors:

Anja Mueller and Philip G. Strange

Field:

Biochemistry, Cell Biology, Immunology

Document Content:

This document investigates the role of the actin cytoskeleton and RhoGTPase family members in the control of ligand-induced internalization and recycling of the chemokine receptor, CCR5. The study utilized stably transfected CHO cells and the monocytic cell line THP-1. It was found that cytochalasin D, an actin depolymerizing agent, inhibited both internalization and recycling of CCR5. Toxin B and C3 exoenzyme, which affect RhoGTPase family activation, also inhibited CCR5 internalization and recycling. However, the Rho kinase inhibitor Y27632 did not affect these processes, indicating that while Rho activation is crucial, ROCK is not directly involved in CCR5 internalization and recycling. The findings suggest that actin polymerization and Rho-dependent signaling are key regulators of CCR5 trafficking.

Detailed Table of Contents:

• Introduction
• Materials and Methods
• Cells and materials
• Chemicals
• Internalization assay and flow cytometry analysis
• Immunofluorescence
• [³⁵S]GTP[γS]-binding assays
• Analysis of intracellular calcium ion concentration
• Results
• Cytochalasin D treatment inhibits CCR5 internalization and recycling
• Internalization of CCR5 is Rho kinase-independent
• Activation of stress fibres and focal adhesion complex formation are ROCK-dependent
• Discussion
• Expression of CCR5 on the cell surface is important for the ability of M-tropic HIV-1 strains to infect cells.
• Internalization and recycling of the receptor back to the cell surface is independent of protein synthesis.
• The study investigated in detail the mechanisms involved in CCR5 internalization and recycling.
• The role of RhoGTPases in CCR5 internalization and recycling, and actin polymerization
• The present report has provided some more details of the pathways involved in the internalization and recycling of CCR5.
• Acknowledgements
• References