Related Experiment Videos
Platelet protease nexin-2/amyloid beta-protein precursor. Possible pathologic and physiologic functions.
W E Van Nostrand1, A H Schmaier, J S Farrow
1Department of Microbiology and Molecular Genetics, University of California, Irvine 92717.
Annals of the New York Academy of Sciences
|January 1, 1991
Summary
Protease nexin-2 (PN-2), the secreted form of amyloid beta-protein precursor (APP), is found in platelets and inhibits blood coagulation factor XIa. This suggests PN-2/APP plays a role in regulating vascular injury and may be implicated in Alzheimer's disease.
Area of Science:
- Neuroscience
- Biochemistry
- Hematology
Background:
- Amyloid beta-protein and its precursor (APP) are central to Alzheimer's disease and Down's syndrome pathology.
- Protease nexin-2 (PN-2) is identified as the secreted form of APP, containing a Kunitz protease inhibitor domain.
- Previous research indicated the presence of circulating PN-2/APP forms.
Purpose of the Study:
- To investigate the role of PN-2/APP as a platelet protein.
- To understand the function of PN-2/APP in blood coagulation and vascular injury.
- To explore the potential contribution of PN-2/APP to Alzheimer's disease pathogenesis.
Main Methods:
- Characterization of PN-2/APP as a platelet alpha granule protein.
- Analysis of PN-2/APP secretion upon platelet activation.
- Protease inhibition assays to determine PN-2/APP's enzymatic targets.
Main Results:
- PN-2/APP is confirmed as a platelet alpha granule protein, secreted upon activation.
- Platelets are identified as the primary circulating source of PN-2/APP.
- PN-2/APP demonstrates potent inhibition of serine proteases, notably factor XIa.
Conclusions:
- PN-2/APP regulates blood coagulation, particularly at sites of vascular injury.
- Platelet-derived PN-2/APP may contribute to amyloid deposition in Alzheimer's disease.
- PN-2/APP's role extends to regulating proteolytic events in vascular settings.