Cofilin-1 Protein
Overview
<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">Cofilin-1 Protein</th>
</tr>
<tr>
<td class="label">Symbol</td>
<td><strong>CFL1</strong></td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>Cofilin-1 (non-muscle)</td>
</tr>
<tr>
<td class="label">Type</td>
<td>Actin-binding protein</td>
</tr>
<tr>
<td class="label">UniProt</td>
<td><a href="https://www.uniprot.org/uniprot/P23528" target="_blank">P23528</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">View in Atlas</a></td>
</tr>
</table>
Cofilin-1 is a small actin-binding protein essential for controlling actin filament dynamics in cells. It belongs to the ADF/cofilin family of proteins and is ubiquitously expressed in non-muscle tissues, including neurons. Cofilin-1 plays a critical role in regulating the actin cytoskeleton by severing and depolymerizing actin filaments, which is fundamental for cellular processes such as cell migration, synaptic plasticity, and neuronal morphology.
Structure and Function
Cofilin-1 is an 18.5 kDa protein consisting of 166 amino acids. It binds to both monomeric (G-actin) and filamentous actin (F-actin), with preferential binding to ADP-bound actin filaments. The protein's activity is regulated primarily through phosphorylation at serine-3 by LIM kinases (LIMK1/LIMK2) and testicular protein kinases (TESK1/TESK2), which inactivates cofilin's actin-severing activity.
...Cofilin-1 Protein
Overview
<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">Cofilin-1 Protein</th>
</tr>
<tr>
<td class="label">Symbol</td>
<td><strong>CFL1</strong></td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>Cofilin-1 (non-muscle)</td>
</tr>
<tr>
<td class="label">Type</td>
<td>Actin-binding protein</td>
</tr>
<tr>
<td class="label">UniProt</td>
<td><a href="https://www.uniprot.org/uniprot/P23528" target="_blank">P23528</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">View in Atlas</a></td>
</tr>
</table>
Cofilin-1 is a small actin-binding protein essential for controlling actin filament dynamics in cells. It belongs to the ADF/cofilin family of proteins and is ubiquitously expressed in non-muscle tissues, including neurons. Cofilin-1 plays a critical role in regulating the actin cytoskeleton by severing and depolymerizing actin filaments, which is fundamental for cellular processes such as cell migration, synaptic plasticity, and neuronal morphology.
Structure and Function
Cofilin-1 is an 18.5 kDa protein consisting of 166 amino acids. It binds to both monomeric (G-actin) and filamentous actin (F-actin), with preferential binding to ADP-bound actin filaments. The protein's activity is regulated primarily through phosphorylation at serine-3 by LIM kinases (LIMK1/LIMK2) and testicular protein kinases (TESK1/TESK2), which inactivates cofilin's actin-severing activity.
In its active (dephosphorylated) state, cofilin-1 performs several key functions:
- Actin severing: Breaks actin filaments into shorter fragments, increasing the number of filament ends
- Depolymerization: Accelerates the dissociation of actin monomers from the pointed end of filaments
- Nucleation: At high concentrations, can nucleate new actin filaments
- pH sensing: Activity is modulated by cellular pH, making it a sensor of metabolic state
Role in the Nervous System
In neurons, cofilin-1 is essential for multiple processes:
Synaptic Plasticity
Cofilin-1 regulates [dendritic spine](/cell-types/dendritic-spines) morphology and synaptic strength. During long-term potentiation (LTP), cofilin activity is transiently suppressed to allow actin polymerization and spine enlargement. Dysregulation of cofilin activity impairs learning and memory formation.
Axonal Growth and Guidance
During development, cofilin-1 controls growth cone motility and axon pathfinding by regulating actin turnover at the leading edge. This dynamic remodeling is essential for responding to guidance cues in the extracellular environment.
Mitochondrial Function
Recent studies have identified cofilin-1 translocation to mitochondria under stress conditions, where it can induce mitochondrial dysfunction and contribute to apoptosis.
Role in Neurodegenerative Disease
Cofilin-1 has emerged as a key player in several neurodegenerative conditions:
Alzheimer's Disease
In [Alzheimer's disease](/diseases/alzheimers-disease), cofilin-1 forms pathological aggregates called cofilin-actin rods in neurons exposed to amyloid-beta oligomers. These rods:
- Disrupt synaptic function and plasticity
- Impair mitochondrial transport along axons
- Contribute to synaptic loss, an early hallmark of AD
- Correlate with cognitive decline in animal models
The formation of cofilin-actin rods is driven by oxidative stress and energy depletion, both prominent features of AD pathology.
Parkinson's Disease
In [Parkinson's disease](/diseases/parkinsons-disease), cofilin-1 activity is altered in dopaminergic neurons. Alpha-synuclein oligomers can activate cofilin through dephosphorylation, leading to:
- Abnormal actin dynamics
- Impaired vesicle trafficking
- Enhanced neuronal vulnerability to stress
Amyotrophic Lateral Sclerosis (ALS)
ALS-associated mutations in genes like C9orf72 and TDP-43 affect cofilin regulation, contributing to cytoskeletal defects in motor neurons.
Therapeutic Potential
Modulating cofilin-1 activity represents a potential therapeutic strategy:
- Cofilin inhibition: Preventing pathological rod formation in AD models preserves synaptic function
- LIMK/ROCK pathway modulation: Targeting upstream kinases could normalize cofilin activity
- Oxidative stress reduction: Antioxidants may prevent cofilin hyperactivation and rod formation
Small molecule modulators of cofilin activity are under investigation as potential neuroprotective agents.
- [Actin](/proteins/actin) - Primary binding partner
- [LIMK1](/proteins/limk1) - Upstream kinase that phosphorylates and inactivates cofilin
- [RhoA](/proteins/rhoa) - GTPase that regulates LIMK activity
- [Alzheimer's Disease](/diseases/alzheimers-disease) - Disease context with cofilin-actin rods
- [Dendritic Spines](/cell-types/dendritic-spines) - Neuronal structures regulated by cofilin
- [Synaptic Plasticity](/mechanisms/synaptic-plasticity) - Process dependent on cofilin regulation
References
Bamburg JR, Bernstein BW. Actin dynamics and cofilin-actin rods in alzheimer disease. Cytoskeleton. 2016;73(9):477-497.
Rust MB. ADF/cofilin: a crucial regulator of synapse physiology and behavior. Cell Mol Life Sci. 2015;72(18):3521-3529.
Bernstein BW, Bamburg JR. Actin-ATP hydrolysis is a major energy drain for neurons. J Neurosci. 2003;23(1):2-6.
Woo JA, et al. Activated cofilin exacerbates tau pathology by impairing tau-mediated microtubule dynamics. Commun Biol. 2019;2:112.External Links
- [UniProt: CFL1](https://www.uniprot.org/uniprot/P23528)
- [GeneCards: CFL1](https://www.genecards.org/cgi-bin/carddisp.pl?gene=CFL1)
- [PubMed: Cofilin and neurodegeneration](https://pubmed.ncbi.nlm.nih.gov/?term=cofilin+neurodegeneration)