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Updated: Aug 8, 2025
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In Vitro Polymerization of F-actin on Early Endosomes
Published on: August 28, 2017
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Arf6 Regulates Endocytosis and Angiogenesis by Promoting Filamentous Actin Assembly
Caitlin R Francis1, Makenzie L Bell1, Marina M Skripnichuk1
1Department of Biological Sciences, University of Denver, Denver, CO.
Biorxiv : the Preprint Server for Biology
|March 3, 2023
Summary
Endothelial Arf6 protein is crucial for blood vessel formation (angiogenesis) by regulating actin and clathrin-mediated endocytosis (CME). Loss of Arf6 disrupts these processes, impacting vascular homeostasis and potentially disease progression.
Area of Science:
- Cell Biology
- Vascular Biology
- Biochemistry
Background:
- Clathrin-mediated endocytosis (CME) is essential for vascular homeostasis and angiogenesis.
- Dysregulated growth factor signaling in diseases like diabetic retinopathy and tumors benefits from CME-targeted therapies.
- ADP ribosylation factor 6 (Arf6) is a GTPase that facilitates actin assembly for CME, potentially impacting pathological signaling.
Approach:
- Investigated the function of Arf6 in angiogenic endothelium.
- Focused on Arf6's role in lumenogenesis and its relationship with actin and CME.
- Utilized 2D cell culture models to analyze Arf6 localization and cellular effects.
Key Points:
- Arf6 was observed at filamentous actin and CME sites in endothelial cells.
- Loss of Arf6 function disrupted endothelial apicobasal polarity.
- Arf6 deficiency led to reduced cellular filamentous actin content, impacting angiogenesis.
Conclusions:
- Endothelial Arf6 plays a significant role in regulating actin dynamics and CME.
- Arf6 is a key mediator of lumen formation and overall angiogenic sprouting.
- Understanding Arf6's function offers insights into vascular development and disease pathology.
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