Related Experiment Video
Updated: Jul 16, 2025
06:51
A Patient-Derived Xenograft Model for Venous Malformation
Published on: June 15, 2020
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rasa1-related arteriovenous malformation is driven by aberrant venous signalling
Jasper Greysson-Wong1,2, Rachael Rode1,3, Jae-Ryeon Ryu1,2
1Alberta Children's Hospital Research Institute, University of Calgary, 3330 University Drive NW, Calgary, AB T2N 4N1, Canada.
Development (Cambridge, England)
|September 14, 2023
Summary
Mutations in RASA1 cause arteriovenous malformations (AVMs) by altering blood flow and vessel remodeling. Blocking MEK/ERK signaling in veins prevents AVM initiation in zebrafish, revealing a key mechanism.
Area of Science:
- Vascular biology
- Genetics
- Developmental biology
Background:
- Arteriovenous malformations (AVMs) result from abnormal endothelial signaling, creating direct artery-to-vein connections.
- Mutations in RASA1 are linked to human AVMs and are investigated here in a zebrafish model.
Purpose of the Study:
- To investigate the mechanisms underlying AVM development in rasa1 mutant zebrafish.
- To identify the molecular pathways involved in AVM initiation and progression.
Main Methods:
- Generation and analysis of rasa1 mutant zebrafish.
- Hemodynamic measurements in the aorta and caudal venous plexus (CVP).
- Gene expression analysis (klf2a) and pathway inhibition (MEK/ERK).
Main Results:
- Rasa1 mutants exhibit cavernous AVMs with altered blood flow dynamics and impaired CVP remodeling.
- Hemodynamic changes correlate with reduced klf2a expression.
- Ectopic MEK/ERK activation in veins drives AVM initiation, and its inhibition prevents AVM formation.
Conclusions:
- RASA1 mutations initiate AVMs through aberrant venous MEK/ERK signaling.
- MEK/ERK pathway modulation offers a potential therapeutic target for AVMs.
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