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The 4-vessel Sampling Approach to Integrative Studies of Human Placental Physiology In Vivo
Published on: August 2, 2017
[Limited proteolysis of integrin alpha v beta3 from human placenta]
O N Lubkova1, T A Gureeva, E A Dilakian
1Hematological Scientific Center of the RAMS, 125167, Moscow, Novoyazikovskiy proyezd, 4a.
Voprosy Meditsinskoi Khimii
|February 24, 2001
Summary
Human placental alpha v beta 3 integrin co-purifies with serine proteinases. Inhibitors prevent degradation, suggesting intact integrin forms complexes with these enzymes.
Area of Science:
- Biochemistry
- Cell Biology
- Integrin Research
Background:
- Integrins are crucial cell surface receptors involved in cell adhesion and signaling.
- Alpha v beta 3 integrin plays a role in various physiological and pathological processes.
- Understanding integrin stability and associated proteins is vital for its functional studies.
Purpose of the Study:
- To purify and characterize alpha v beta 3 integrin from human placenta.
- To investigate the stability and degradation of purified alpha v beta 3 integrin.
- To identify associated proteins and their impact on integrin function.
Main Methods:
- Affinity chromatography using monoclonal antibodies and RGD-peptide.
- Incubation at 37°C to assess degradation.
- Assay for serine proteinase activity.
- Use of serine proteinase inhibitors (PMSF, leupeptin, aprotinin).
Main Results:
- Partially degraded alpha v beta 3 integrin was purified, retaining ligand-binding ability.
- Further degradation occurred upon incubation, which was inhibited by serine proteinase inhibitors.
- Urokinase and dipeptidyl peptidase IV activities were detected in purified preparations.
- Degraded alpha v beta 3 integrin exhibited reduced affinity for RGD peptide.
Conclusions:
- Human placental alpha v beta 3 integrin co-purifies with endogenous serine proteinases.
- These associated serine proteinases contribute to the limited proteolysis of the integrin.
- A stable complex likely forms between functionally active alpha v beta 3 integrin and serine proteinases during extraction.
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