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Updated: Jun 14, 2026
11:29
Investigation of Synaptic Tagging/Capture and Cross-capture using Acute Hippocampal Slices from Rodents
Published on: September 4, 2015
AP-1/sigma1B-adaptin mediates endosomal synaptic vesicle recycling, learning and memory
Nataliya Glyvuk1, Yaroslav Tsytsyura, Constanze Geumann
1Institute of Medical Physics and Biophysics, University of Münster, Münster, Germany.
The EMBO Journal
|March 6, 2010
Summary
The AP-1-sigma1B complex is crucial for synaptic vesicle recycling in the brain. Its deficiency impairs vesicle reformation, leading to cognitive and motor deficits, and reveals a mechanism for X-linked mental retardation.
Area of Science:
- Neuroscience
- Cell Biology
- Molecular Biology
Background:
- Synaptic vesicle recycling is essential for neurotransmission.
- The role of the endosomal pathway and specific adaptor protein complexes (AP-1) in this process remains unclear.
- Vertebrates have three sigma1 subunit isoforms (A, B, C) with high expression of A and B in the brain.
Purpose of the Study:
- To investigate the role of the AP-1-sigma1B complex in synaptic vesicle recycling.
- To determine the impact of AP-1-sigma1B deficiency on neuronal function and behavior.
Main Methods:
- Generation and analysis of mice deficient in the AP-1-sigma1B complex.
- Assessment of synaptic vesicle recycling and reformation in hippocampal synapses.
- Evaluation of motor coordination and spatial memory in knockout mice.
Main Results:
- Mice lacking AP-1-sigma1B exhibit impaired synaptic vesicle recycling in hippocampal synapses.
- Reduced synaptic vesicle reformation and accumulation of endosomal intermediates were observed in sigma1B-deficient neurons.
- These mice displayed significant deficits in motor coordination and long-term spatial memory.
Conclusions:
- The AP-1-sigma1B complex plays a critical role in synaptic vesicle reformation and recycling.
- Disruption of this complex leads to neurological impairments, including cognitive and motor deficits.
- These findings elucidate a molecular mechanism underlying severe human X-chromosome-linked mental retardation.
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