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Updated: Jul 25, 2026

Purification of Platelets from Mouse Blood

Purification of Platelets from Mouse Blood

Published on: May 7, 2019

Rap1b is required for normal platelet function and hemostasis in mice.

Magdalena Chrzanowska-Wodnicka¹, Susan S Smyth, Simone M Schoenwaelder

¹Department of Medicine and Carolina Cardiovascular Biology Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA. Magdalena_Wodnicka@med.unc.edu.

The Journal of Clinical Investigation

|February 8, 2005

Summary

Rap1b deficiency in mice causes bleeding defects due to impaired platelet aggregation and integrin activation. These findings highlight Rap1b

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Purification of Platelets from Mouse Blood

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Published on: May 7, 2019

Proplatelet Formation Dynamics of Mouse Fresh Bone Marrow Explants

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Published on: May 20, 2021

In Vivo Two-photon Imaging of Megakaryocytes and Proplatelets in the Mouse Skull Bone Marrow

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Published on: July 28, 2021

Area of Science:

Biochemistry
Hematology
Molecular Biology

Background:

Rap1b is a small GTPase abundant in platelets.
Its precise role in platelet function, downstream of GPCRs and upstream of integrin alpha IIbbeta3, remains unclear.

Purpose of the Study:

To investigate the role of Rap1b in platelet function and hemostasis.
To determine if Rap1b is essential for integrin activation and thrombosis.

Main Methods:

Generation of a murine Rap1b knockout model.
Assessment of platelet aggregation in response to various agonists.
Analysis of integrin alpha IIbbeta3 activation and downstream signaling.
Evaluation of in vivo hemostasis and arterial thrombosis.

Main Results:

Rap1b-null platelets exhibit reduced aggregation upon stimulation.
Integrin alpha IIbbeta3 activation and downstream signaling are impaired in Rap1b-deficient platelets.
Rap1b-null mice show bleeding defects and are protected from arterial thrombosis.

Conclusions:

Rap1b is crucial for normal platelet function and hemostasis.
Rap1b acts in a common pathway for integrin activation.
Rap1b represents a potential therapeutic target for antithrombotic strategies.