Related Experiment Videos
Fibronectin binding by brain synaptosomal membranes may not involve conventional integrins
B A Bahr1, A Sheppard, G Lynch
1Center for the Neurobiology of Learning and Memory, University of California, Irvine 92717.
Neuroreport
|January 1, 1991
Summary
Researchers identified novel fibronectin-binding peptides in rat brain synaptosomal plasma membranes (SPMs). These peptides, distinct from known integrins, may play a role in synaptic adhesion.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Synaptosomes are crucial for neuronal communication.
- Plasma membranes of synaptosomes contain receptors for extracellular matrix proteins.
- Integrins are known fibronectin receptors.
Purpose of the Study:
- To investigate fibronectin binding and antigenicity in rat brain synaptosomal plasma membranes (SPMs).
- To identify potential novel receptors involved in synaptic adhesion.
Main Methods:
- Western blotting and immunoprecipitation using antibodies against integrin-type fibronectin receptors.
- Analysis of fibronectin binding to SPMs and brain homogenates.
- Peptide characterization using antibodies against hamster ovarian fibronectin receptor.
Main Results:
- Fibronectin binding was significantly higher in SPMs from hippocampus and neocortex compared to homogenates.
- The tetrapeptide L-arginyl-glycyl-L-aspartyl-L-serine inhibited binding, confirming integrin-type receptor presence.
- SPMs showed concentrated polypeptides of 55,000 and 40,000 Mr, distinct from known integrins, reacting with anti-fibronectin receptor antibodies.
Conclusions:
- SPMs contain novel fibronectin-binding peptides, not typical integrins.
- These novel peptides are highly concentrated in SPMs and may represent a new class of matrix receptors.
- These receptors are potentially involved in synaptic adhesion and neuronal function.