MAP2 Protein

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protein1263 wordssynced 2026-04-02

MAP2 Protein

Overview

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MAP2 Protein

Overview

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">MAP2 Protein</th>
</tr>
<tr>
<td class="label">Protein Symbol</td>
<td>MAP2</td>
</tr>
<tr>
<td class="label">Protein Name</td>
<td>Microtubule-Associated Protein 2</td>
</tr>
<tr>
<td class="label">Aliases</td>
<td>MAP-2, MAP2A, MAP2B, MAP2C, MAP2D</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>2q34-q35</td>
</tr>
<tr>
<td class="label">Entrez Gene ID</td>
<td>4135</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>P29536</td>
</tr>
<tr>
<td class="label">Isoforms</td>
<td>Multiple (MAP2A, MAP2B, MAP2C, MAP2D)</td>
</tr>
<tr>
<td class="label">Tissue Specificity</td>
<td>Neuron-specific</td>
</tr>
<tr>
<td class="label">Domain</td>
<td>Position</td>
</tr>
<tr>
<td class="label">N-terminal projection domain</td>
<td>1-1500 aa</td>
</tr>
<tr>
<td class="label">Microtubule-binding domain</td>
<td>1500-1800 aa</td>
</tr>
<tr>
<td class="label">C-terminal domain</td>
<td>1800-2000+ aa</td>
</tr>
<tr>
<td class="label">Isoform</td>
<td>Molecular Weight</td>
</tr>
<tr>
<td class="label">MAP2A</td>
<td>~200 kDa</td>
</tr>
<tr>
<td class="label">MAP2B</td>
<td>~200 kDa</td>
</tr>
<tr>
<td class="label">MAP2C</td>
<td>~70 kDa</td>
</tr>
<tr>
<td class="label">MAP2D</td>
<td>~200 kDa</td>
</tr>
<tr>
<td class="label">Dendritic localization</td>
<td>Concentrated in dendritic shafts and spines</td>
</tr>
<tr>
<td class="label">Spine morphology</td>
<td>Regulates dendritic spine shape and stability</td>
</tr>
<tr>
<td class="label">Synaptic targeting</td>
<td>Localizes to postsynaptic densities</td>
</tr>
<tr>
<td class="label">Signal transduction</td>
<td>Scaffold for signaling molecules</td>
</tr>
<tr>
<td class="label">Change</td>
<td>Description</td>
</tr>
<tr>
<td class="label">Reduced immunoreactivity</td>
<td>Decreased MAP2 staining</td>
</tr>
<tr>
<td class="label">Dendritic degeneration</td>
<td>Beading, fragmentation</td>
</tr>
<tr>
<td class="label">Colocalization with plaques</td>
<td>MAP2 around amyloid</td>
</tr>
<tr>
<td class="label">Correlation with cognition</td>
<td>MAP2 loss tracks dementia</td>
</tr>
<tr>
<td class="label">Disease</td>
<td>MAP2 Relationship</td>
</tr>
<tr>
<td class="label">Huntington's disease</td>
<td>Reduced MAP2 in striatal neurons</td>
</tr>
<tr>
<td class="label">Frontotemporal dementia</td>
<td>Tau pathology affects MAP2</td>
</tr>
<tr>
<td class="label">Multiple sclerosis</td>
<td>Marker of demyelination damage</td>
</tr>
<tr>
<td class="label">Traumatic brain injury</td>
<td>MAP2 as injury biomarker</td>
</tr>
<tr>
<td class="label">Mechanism</td>
<td>Description</td>
</tr>
<tr>
<td class="label">Microtubule disruption</td>
<td>Loss of stabilization leads to transport defects</td>
</tr>
<tr>
<td class="label">Synaptic loss</td>
<td>Reduced synaptic MAP2 precedes neuron death</td>
</tr>
<tr>
<td class="label">Phosphorylation imbalance</td>
<td>Abnormal kinases/phosphatases affect MAP2</td>
</tr>
<tr>
<td class="label">Proteasomal degradation</td>
<td>Increased MAP2 cleavage in disease</td>
</tr>
<tr>
<td class="label">Biomarker Use</td>
<td>Application</td>
</tr>
<tr>
<td class="label">Neuronal injury</td>
<td>CSF/serum MAP2</td>
</tr>
<tr>
<td class="label">Disease progression</td>
<td>Brain MAP2 loss</td>
</tr>
<tr>
<td class="label">Therapeutic monitoring</td>
<td>MAP2 recovery</td>
</tr>
<tr>
<td class="label">Autopsy tissue</td>
<td>MAP2 immunostaining</td>
</tr>
<tr>
<td class="label">Partner</td>
<td>Interaction Type</td>
</tr>
<tr>
<td class="label">β-Tubulin</td>
<td>Direct binding</td>
</tr>
<tr>
<td class="label">Tau</td>
<td>Competition</td>
</tr>
<tr>
<td class="label">PSD-95</td>
<td>Scaffold binding</td>
</tr>
<tr>
<td class="label">NMDA receptor</td>
<td>Direct binding</td>
</tr>
<tr>
<td class="label">CaMKII</td>
<td>Phosphorylation</td>
</tr>
<tr>
<td class="label">MARK kinases</td>
<td>Phosphorylation</td>
</tr>
<tr>
<td class="label">Fyn kinase</td>
<td>Phosphorylation</td>
</tr>
<tr>
<td class="label">Region</td>
<td>MAP2 Expression</td>
</tr>
<tr>
<td class="label">Hippocampus</td>
<td>Very high (CA1-CA3, dentate gyrus)</td>
</tr>
<tr>
<td class="label">Cerebral cortex</td>
<td>High (layers II-VI)</td>
</tr>
<tr>
<td class="label">Cerebellum</td>
<td>Moderate (Purkinje cell dendrites)</td>
</tr>
<tr>
<td class="label">Basal ganglia</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Brainstem</td>
<td>Lower</td>
</tr>
<tr>
<td class="label">Kinase</td>
<td>Site</td>
</tr>
<tr>
<td class="label">CaMKII</td>
<td>Multiple serine/threonine</td>
</tr>
<tr>
<td class="label">PKA</td>
<td>Serine residues</td>
</tr>
<tr>
<td class="label">MARK/PAR-1</td>
<td>KXGS motifs</td>
</tr>
<tr>
<td class="label">GSK-3β</td>
<td>Multiple sites</td>
</tr>
<tr>
<td class="label">CDK5</td>
<td>Proline-directed sites</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/ad" style="color:#ef9a9a">AD</a>, <a href="/wiki/ali" style="color:#ef9a9a">ALI</a>, <a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/ami" style="color:#ef9a9a">AMI</a>, <a href="/wiki/aging" style="color:#ef9a9a">Aging</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">140 edges</a></td>
</tr>
</table>

MAP2 (Microtubule-Associated Protein 2) is a neuronal cytoskeletal protein that plays critical roles in stabilizing microtubules, maintaining dendritic architecture, and regulating synaptic function. As one of the most abundant proteins in neurons, MAP2 is essential for proper neuronal development, axonal transport, and plasticity. It serves as a key biomarker for neuronal injury and is heavily implicated in the pathogenesis of Alzheimer's disease and other neurodegenerative disorders. [@shafitzagardo1999]

Protein Structure and Isoforms

Structural Architecture

MAP2 is a large protein with distinct structural domains:

Isoforms

The MAP2 gene produces multiple isoforms through alternative splicing:

Microtubule-Binding Repeat Regions

MAP2 contains 3-4 repeat sequences in its microtubule-binding domain:

Repeat 1: 1766-1790 aa
Repeat 2: 1791-1815 aa
Repeat 3: 1816-1840 aa
Repeat 4 (if present): 1841-1865 aa

These repeats bind to the C-terminal tails of β-tubulin, stabilizing microtubule structure.

Biological Functions

Microtubule Stabilization

MAP2's primary function is stabilizing neuronal microtubules:

Polymer protection: Prevents microtubule depolymerization
Bundle formation: Organizes microtubules into parallel bundles
Transport facilitation: Enables microtubule-based transport
Dynamic regulation: Modulates microtubule dynamics

Dendritic Architecture

MAP2 is specifically enriched in dendrites (not axons):

Synaptic Function

MAP2 plays essential roles at synapses:

Postsynaptic scaffold: Links postsynaptic densities to cytoskeleton

Receptor anchoring: Interacts with NMDA and AMPA receptors

Signal integration: Scaffold for multiple signaling pathways

Plasticity modulation: Involved in LTP and LTD

Developmental Roles

Neuronal differentiation: Guides neuronal polarity establishment
Dendritogenesis: Essential for dendritic tree formation
Synaptogenesis: Regulates synapse formation and maturation
Migration: Modulates neuronal migration in developing brain

Role in Neurodegenerative Diseases

Alzheimer's Disease

MAP2 is intimately involved in AD pathogenesis:

Tau Pathology Interaction

Competition for binding: Hyperphosphorylated tau competes with MAP2 for microtubule binding
Loss of function: Tau pathology reduces MAP2-microtubule interaction
Structural destabilization: Combined loss leads to dendritic breakdown
Diagnostic marker: MAP2 immunoreactivity reflects neuronal integrity

Changes in Alzheimer's Brain

Parkinson's Disease

Dendritic vulnerability: Dopaminergic neuron dendrites affected
Synaptic dysfunction: Loss of synaptic MAP2
α-Synuclein interaction: Potential crosstalk with microtubule function
Therapeutic implications: MAP2 as intervention target

Other Neurodegenerative Conditions

Mechanisms of Neurodegeneration

Clinical Significance

Biomarker Applications

Therapeutic Target Potential

Microtubule stabilization: Compounds to enhance MAP2 function
Phosphorylation modulation: Kinase/phosphatase targeting
Gene therapy: MAP2 expression restoration
Small molecule stabilizers: Taxol-like compounds

Interactions and Pathway Membership

Protein Interactions

Pathway Involvement

MAP2 participates in several key pathways:

Cytoskeletal organization pathway: Core component of neuronal cytoskeleton
Synaptic plasticity pathway: Postsynaptic scaffolding
MAP kinase signaling: Regulated by phosphorylation
Axonal transport pathway: Facilitates intracellular transport

Animal Models

Knockout Models

Map2 knockout mice exhibit:

Motor deficits: Coordination and balance problems
Learning impairments: Reduced spatial learning
Dendritic abnormalities: Altered dendritic tree morphology
Synaptic defects: Impaired synaptic plasticity

Transgenic Models

MAP2 overexpression: Enhanced neuronal survival
Mutant MAP2: Disease-like phenotypes
Rescue experiments: Functional restoration

Expression Patterns

Brain Region Distribution

Cellular Localization

Soma: Perikaryal cytoplasm
Dendrites: High concentration in shafts and spines
Synapses: Postsynaptic density
Axons: Very low (distinguishes from tau)

Phosphorylation Regulation

Kinases Regulating MAP2

Phosphorylation States

Highly phosphorylated: Reduced microtubule binding
Hypophosphorylated: Tight microtubule association
Dynamic regulation: Activity-dependent changes

External Links

[PubMed](https://pubmed.ncbi.nlm.nih.gov/)
[KEGG Pathways](https://www.genome.jp/kegg/pathway.html)

References

[Matus et al., MAP2 organization in neurons (1981) (1981)](https://doi.org/10.1083/jcb.91.2.414a)

[Halpain et al., MAP2 function in dendrites (1998) (1998)](https://doi.org/10.1146/annurev.neuro.21.1.145)

[Dehmelt et al., MAP2 and tau dynamics (2003) (2003)](https://doi.org/10.1083/jcb.200301055)

[Harada et al., MAP2 in Alzheimer's disease (2002) (2002)](https://doi.org/10.1093/jnen/61.10.917)

[Binder et al., MAP2 as neuronal marker (1985) (1985)](https://doi.org/10.1083/jcb.101.4.1371)

[Chen et al., MAP2 phosphorylation (1992) (1992)](https://doi.org/10.1016/0092-8674(92)

[Sanchez et al., MAP2 and microtubule dynamics (2000) (2000)](https://doi.org/10.1242/jcs.113.19.3209)

[Ramakers et al., MAP2 and synaptic plasticity (2001) (2001)](https://doi.org/10.1016/S0306-4522(01)

[Kim et al., MAP2 in neurodegeneration (2007) (2007)](https://doi.org/10.1016/j.tins.2007.08.005)

[Teng et al., MAP2 in traumatic brain injury (2001) (2001)](https://doi.org/10.1089/089771501753093804)

[Shafit-Zagardo et al., MAP2 isoforms (1999) (1999)](https://doi.org/10.1016/S0165-5728(98)

[Johnson et al., MAP2 and cytoskeletal signaling (2000) (2000)](https://doi.org/10.1016/S0092-8674(00)

[Baudier et al., MAP2 phosphorylation by kinases (1987) (1987)](https://doi.org/10.1021/bi00230a012)

[Tucker et al., MAP2 in dendritic spines (1990) (1990)](https://doi.org/10.1083/jcb.111.1.199)

[Avila et al., Tau and MAP2 in disease (1994) (1994)](https://doi.org/10.1016/0301-0082(94)

[Mandelkow et al., MAP2 interactions with tau (1995) (1995)](https://doi.org/10.1016/0166-2236(95)

[Squier et al., MAP2 in developmental neurobiology (2001) (2001)](https://doi.org/10.1016/S0301-0082(00)

[Fischer et al., MAP2 and cognitive decline (2009) (2009)](https://doi.org/10.1016/j.neurobiolaging.2008.02.018)

[Merriam et al., MAP2 gene regulation (1983) (1983)](https://doi.org/10.1073/pnas.80.22.7183)

[Drubin et al., MAP2 and neuronal polarity (1985) (1985)](https://doi.org/10.1038/315245a0)

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MAP2 Protein

MAP2 Protein

Overview

MAP2 Protein

Overview

Protein Structure and Isoforms

Structural Architecture

Isoforms

Microtubule-Binding Repeat Regions

Biological Functions

Microtubule Stabilization

Dendritic Architecture

Synaptic Function

Developmental Roles

Role in Neurodegenerative Diseases

Alzheimer's Disease

Tau Pathology Interaction

Changes in Alzheimer's Brain

Parkinson's Disease

Other Neurodegenerative Conditions

Mechanisms of Neurodegeneration

Clinical Significance

Biomarker Applications

Therapeutic Target Potential

Interactions and Pathway Membership

Protein Interactions

Pathway Involvement

Animal Models

Knockout Models

Transgenic Models

Expression Patterns

Brain Region Distribution

Cellular Localization

Phosphorylation Regulation

Kinases Regulating MAP2

Phosphorylation States

See Also

External Links

References