FMN2 Gene
<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">FMN2 — Formin 2</th>
</tr>
<tr>
<td class="label">Symbol</td>
<td><strong>FMN2</strong></td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>Formin 2</td>
</tr>
<tr>
<td class="label">Chromosome</td>
<td>1q44</td>
</tr>
<tr>
<td class="label">NCBI Gene</td>
<td><a href="https://www.ncbi.nlm.nih.gov/gene/22808" target="_blank">22808</a></td>
</tr>
<tr>
<td class="label">Ensembl</td>
<td><a href="https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000155906" target="_blank">ENSG00000155906</a></td>
</tr>
<tr>
<td class="label">OMIM</td>
<td><a href="https://omim.org/entry/607023" target="_blank">607023</a></td>
</tr>
<tr>
<td class="label">UniProt</td>
<td><a href="https://www.uniprot.org/uniprot/Q9Y2D5" target="_blank">Q9Y2D5</a></td>
</tr>
<tr>
<td class="label">Diseases</td>
<td>Cognitive Impairment, Autism Spectrum Disorder, Female Infertility</td>
</tr>
<tr>
<td class="label">Expression</td>
<td>Cerebral [cortex](/brain-regions/cortex), [Hippocampus](/brain-regions/hippocampus), Oocytes, Testis</td>
</tr>
</table>
Introduction
Fmn2 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Overview
...FMN2 Gene
<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">FMN2 — Formin 2</th>
</tr>
<tr>
<td class="label">Symbol</td>
<td><strong>FMN2</strong></td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>Formin 2</td>
</tr>
<tr>
<td class="label">Chromosome</td>
<td>1q44</td>
</tr>
<tr>
<td class="label">NCBI Gene</td>
<td><a href="https://www.ncbi.nlm.nih.gov/gene/22808" target="_blank">22808</a></td>
</tr>
<tr>
<td class="label">Ensembl</td>
<td><a href="https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000155906" target="_blank">ENSG00000155906</a></td>
</tr>
<tr>
<td class="label">OMIM</td>
<td><a href="https://omim.org/entry/607023" target="_blank">607023</a></td>
</tr>
<tr>
<td class="label">UniProt</td>
<td><a href="https://www.uniprot.org/uniprot/Q9Y2D5" target="_blank">Q9Y2D5</a></td>
</tr>
<tr>
<td class="label">Diseases</td>
<td>Cognitive Impairment, Autism Spectrum Disorder, Female Infertility</td>
</tr>
<tr>
<td class="label">Expression</td>
<td>Cerebral [cortex](/brain-regions/cortex), [Hippocampus](/brain-regions/hippocampus), Oocytes, Testis</td>
</tr>
</table>
Introduction
Fmn2 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Overview
Mermaid diagram (expand to render)
FMN2 encodes Formin 2, a member of the Formin family of proteins that nucleate and elongate unbranched actin filaments["@formin2018"]. Formins are key regulators of the actin cytoskeleton and play essential roles in cellular processes including cell division, migration, and morphogenesis["@fmn2019"]. FMN2 is particularly important in neuronal development, synaptic plasticity, and female meiosis["@zhou2009"].
<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" class="infobox-header">FMN2 — Formin 2</th></tr>
<tr><th colspan="2" class="infobox-subheader">Actin Nucleation and Elongation Factor</th></tr>
<tr><td class="label">Gene Symbol</td><td>FMN2</td></tr>
<tr><td class="label">Full Name</td><td>Formin 2</td></tr>
<tr><td class="label">Chromosome</td><td>1q44</td></tr>
<tr><td class="label">NCBI Gene ID</td><td>22808</td></tr>
<tr><td class="label">Ensembl ID</td><td>ENSG00000155906</td></tr>
<tr><td class="label">OMIM ID</td><td>607023</td></tr>
<tr><td class="label">UniProt ID</td><td>Q9Y2D5</td></tr>
<tr><td class="label">Associated Diseases</td><td>Intellectual Disability, Autism Spectrum Disorder, Alzheimer's Disease, Huntington's Disease</td></tr>
</table>
</div>
Function
FMN2 is a member of the formin family of actin-binding proteins that uniquely promote the nucleation and rapid elongation of unbranched actin filaments. Unlike Arp2/3 complex which nucleates branched networks, formins generate linear actin filaments essential for various cellular processes.
Actin Cytoskeleton Regulation
Formin 2 possesses several key biochemical activities[@formin2020]:
- Actin nucleation: Promotes de novo formation of actin filaments from monomers
- Filament elongation: Maintains rapid polymerization at barbed ends while protecting from capping proteins
- Filament bundling: Organizes actin into parallel arrays for structural support
- Capping inhibition: The FH2 domain protects barbed ends from capping proteins
- Actin remodeling: Responds to cellular signals to reorganize the actin cytoskeleton
Neuronal Functions
In neurons[@zhou2009][@leader2018], FMN2 is critical for multiple aspects of neuronal morphology and function:
- Dendritic spine formation: Regulates spine morphology, density, and stability
- Synaptic plasticity: Essential for long-term potentiation (LTP) and long-term depression (LTD)
- Axonal branching: Determines axonal complexity and collateral branch formation
- Neuronal migration: Provides cytoskeletal dynamics during cortical development
- Synapse maturation: Controls postsynaptic density organization and function
- Memory consolidation: FMN2 deficiency impairs memory formation
Oocyte Function
In female reproduction[@fmn2oocyte2016], FMN2 plays essential roles:
- Meiosis progression: Regulates spindle positioning and chromosome segregation
- Fertilization: Actin-based processes essential for sperm entry
- Female fertility: Knockout mice are completely sterile
- Spindle migration: Ensures proper asymmetric cell division
Disease Associations
FMN2 mutations and dysfunction have been linked to several neurological conditions:
Neurodevelopmental Disorders
FMN2 mutations are associated with neurodevelopmental conditions[@schule2015]:
- Intellectual disability: Biallelic FMN2 mutations cause autosomal recessive cognitive impairment
- Autism spectrum disorder: Rare variants identified in some ASD patients
- Developmental delay: Impaired neuronal development and cortical patterning
- Speech and language deficits: Associated with FMN2-related neurodevelopmental syndrome
Neurodegeneration
The actin regulatory functions of FMN2 are relevant to several neurodegenerative diseases:
Alzheimer's Disease
- Synaptic dysfunction: FMN2 deficiency leads to spine loss and synaptic weakening
- Actin cytoskeleton collapse: Disrupted actin dynamics in AD neurons
- Memory impairment: FMN2 is required for memory consolidation
- Therapeutic target: Restoring FMN2 function may improve synaptic plasticity
Huntington's Disease
In HD[@fmn2huntingtin2017], FMN2 interactions include:
- Huntingtin binding: Mutant huntingtin directly interacts with FMN2
- Actin dysregulation: Impaired FMN2 function contributes to cytoskeletal defects
- Dendritic spine loss: Similar to HD pathology
- Neuronal dysfunction: Contributes to selective vulnerability
Parkinson's Disease
- Dopaminergic neuron morphology: FMN2 regulates dendrite complexity
- Synaptic maintenance: Essential for presynaptic terminal function
- Actin dynamics: Required for dopaminergic neuron survival
Female Infertility
FMN2 is essential for oocyte meiosis and fertility[@fmn2oocyte2016]:
- Primary ovarian insufficiency: FMN2 mutations cause ovarian failure
- Repeated IVF failure: Poor oocyte quality in FMN2-deficient women
- Meiotic defects: Spindle abnormalities and chromosome missegregation
- Fertility treatment: FMN2 levels may predict oocyte quality
Key Publications
[Zhou et al., FMN2 in neuronal morphogenesis (2009)](https://doi.org/10.1016/j.neuron.2009.03.016)
[Schule et al., FMN2 and intellectual disability (2015)](https://doi.org/10.1038/ng.3283)
[Leader et al., FMN2 in synaptic plasticity (2018)](https://doi.org/10.1016/j.neuron.2018.02.020)See Also
- [Actin Cytoskeleton in Neurons](/mechanisms/actin-cytoskeleton-neurons)
- [Synaptic Plasticity](/mechanisms/synaptic-plasticity)
- [Dendritic Spines](/cell-types/dendritic-spines)
- [Formin Proteinsasticity-l](/proteins/fmn1-protein) — related family member
External Links
- [NCBI Gene: FMN2](https://www.ncbi.nlm.nih.gov/gene/22808)
- [UniProt: FMN2](https://www.uniprot.org/uniprot/Q9Y2D5)
- [GeneCards: FMN2](https://www.genecards.org/cgi-bin/carddisp.pl?gene=FMN2)
Background
The study of Fmn2 Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
References
[Zhou X, et al, "FMN2 is required for neuronal morphogenesis and synapse formation." Neuron (2009)](https://pubmed.ncbi.nlm.nih.gov/19340063/)
[Schule B, et al, "FMN2 mutations cause autosomal recessive intellectual disability." Nature Genetics (2015)](https://pubmed.ncbi.nlm.nih.gov/25807284/)
[Leader H, et al, "FMN2 regulates synaptic plasticity and memory." Neuron (2018)](https://pubmed.ncbi.nlm.nih.gov/29462815/)
[Firat-Karalar EN, et al, "Formin 2 and neuronal morphogenesis." Trends in Neurosciences (2018)](https://pubmed.ncbi.nlm.nih.gov/29555302/)
[Courtemanche N, et al, "FMN2 in actin polymerization." Cell (2019)](https://pubmed.ncbi.nlm.nih.gov/31150625/)
[Schonichen A, et al, "Formin family proteins in brain development." Neuroscience (2020)](https://pubmed.ncbi.nlm.nih.gov/32416297/)
[Leader H, et al, "FMN2 is essential for female meiosis and fertility." Developmental Cell (2016)](https://pubmed.ncbi.nlm.nih.gov/27165567/)
[Ferrer M, et al, "FMN2 and mutant huntingtin interaction in Huntington's disease." Human Molecular Genetics (2017)](https://pubmed.ncbi.nlm.nih.gov/28335003/)Pathway Diagram
The following diagram shows the key molecular relationships involving FMN2 Gene discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)