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Preparation of Synaptic Plasma Membrane and Postsynaptic Density Proteins Using a Discontinuous Sucrose Gradient
Published on: September 3, 2014
Phosphorylated synaphin/complexin found in the brain exhibits enhanced SNARE complex binding.
Atsushi Shata1, Hideo Saisu, Shoji Odani
1Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata 951-8585, Japan.
Biochemical and Biophysical Research Communications
|February 3, 2007
Summary
Protein kinase CK2 phosphorylates synaphins (Syps) at Ser-115, enhancing their binding to SNARE complexes. This phosphorylation regulates fast neurotransmitter release in the brain.
Area of Science:
- Neuroscience
- Molecular Biology
- Biochemistry
Background:
- Synaphins (Syps) are crucial for fast neurotransmitter release by interacting with SNARE complexes.
- The precise mechanism and physiological regulation of synaphin function are not fully understood.
Purpose of the Study:
- To investigate the potential regulation of synaphins by phosphorylation.
- To identify the kinase responsible and the specific phosphorylation sites involved.
Main Methods:
- In vitro phosphorylation assays using protein kinase CK2 (CK2) and synaphins (Syps) 1 and 2.
- Analysis of phosphorylation sites using specific antibodies.
- Biochemical assays to measure Syp-SNARE complex affinity.
- Detection of phosphorylated Syp 1 in rat brain cytosolic fractions.
Main Results:
- CK2 phosphorylates Syps 1 and 2 specifically at serine-115 (Ser-115).
- Phosphorylation at Ser-115 increases the affinity of Syps 1 and 2 for SNARE complexes.
- Ser-115-phosphorylated Syp 1 was detected in rat brain cytosol.
Conclusions:
- Synaphin activity is regulated by CK2-mediated phosphorylation at Ser-115 in vivo.
- This phosphorylation mechanism offers a novel pathway for modulating fast neurotransmitter release.
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