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Megakaryocyte Differentiation and Platelet Formation from Human Cord Blood-derived CD34+ Cells
Published on: December 27, 2017
Observations on the "Cytoskeleton" of Human Platelets
V T Nachmias1, J Sullender1, J Fallon1
1The Department of Anatomy, School of Medicine, University of Pennsylvania, Philadelphia, U.S.A.
Thrombosis and Haemostasis
|February 21, 2019
Summary
Platelet shape change involves microfilament state changes. Local anesthetics disrupt filopodia formation by affecting a high molecular weight protein in platelets.
Area of Science:
- Cell Biology
- Biochemistry
- Hematology
Background:
- Platelets are crucial for hemostasis and thrombosis.
- Understanding platelet shape change is key to platelet function.
- Microfilaments and microtubules are important cytoskeletal components in platelets.
Purpose of the Study:
- To investigate the structural basis of platelet shape change.
- To explore the role of microfilaments and microtubules in platelet morphology.
- To identify molecular changes associated with the loss of filopodia formation.
Main Methods:
- Structural analysis of rapidly lysed platelets.
- Observation of microtubule organization.
- Proteolysis assays to identify protein changes.
Main Results:
- Platelet shape change correlates with alterations in actin-containing microfilaments.
- Platelet microtubules form a continuous coil structure.
- Suppression of filopodia by local anesthetics is linked to proteolysis of a high molecular weight protein.
Conclusions:
- Platelet shape change is mediated by microfilament rearrangements.
- Microtubules form a stable coiled structure within platelets.
- A specific high molecular weight protein is implicated in filopodia formation and is targeted by local anesthetics.
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