Related Experiment Video
Updated: May 24, 2026
10:29
Morphological and Functional Evaluation of Axons and their Synapses during Axon Death in Drosophila melanogaster
Published on: March 16, 2020
Age-related decline in nuclear envelope LINC complex drives neuronal aging via axon initial segment dysfunction.
Koichi Hasegawa1, Noriyuki Hama1,2, Mina Amemiya1
1Department of Neural and Muscular Physiology, School of Medicine, Shimane University, Izumo, Japan.
EMBO Reports
|May 22, 2026
Summary
Brain aging involves declining LINC complex expression, impairing axon initial segment (AIS) function and triggering cognitive decline. Restoring Sun1, a LINC component, rejuvenates neuronal function and preserves brain health.
Area of Science:
- Neuroscience
- Molecular Biology
- Aging Research
Background:
- Brain aging leads to functional decline, but molecular causes are poorly understood.
- The LINC complex's role in neuronal aging is largely unexplored.
Purpose of the Study:
- To investigate the molecular mechanisms linking LINC complex dysfunction to brain aging.
- To identify key molecular players, such as Sun1, involved in age-related neuronal changes.
Main Methods:
- Examined LINC complex component expression (e.g., Sun1) in aging brains.
- Assessed axon initial segment (AIS) integrity and neuronal excitability in young and aged mice.
- Manipulated Sun1 expression in aged neurons and young mice to determine its functional impact.
Main Results:
- Aging significantly reduces LINC complex expression, including Sun1, and shortens AIS length.
- Preserving Sun1 expression in aged neurons corrects nuclear abnormalities and restores gene expression patterns of young neurons.
- Sun1 restoration re-establishes AIS-related molecule expression and neuronal excitability.
- Inhibiting the LINC complex in young mice induces AIS dysfunction and cognitive deficits.
Conclusions:
- Age-related decline in LINC complex expression, particularly Sun1, drives AIS dysfunction and brain aging.
- Sun1 is crucial for maintaining nuclear structure, gene expression, and neuronal excitability.
- Targeting Sun1 offers a potential therapeutic strategy for age-related brain dysfunction.
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