CSNK2A1 Gene
<div class="infobox infobox-gene">
<h3>CSNK2A1</h3>
<table>
<tr><th>Full Name</th><td>Casein Kinase 2 Alpha 1</td></tr>
<tr><th>Gene Symbol</th><td>CSNK2A1</td></tr>
<tr><th>Chromosome</th><td>20p13</td></tr>
<tr><th>NCBI Gene ID</th><td>[1457](https://www.ncbi.nlm.nih.gov/gene/1457)</td></tr>
<tr><th>OMIM</th><td>[115440](https://omim.org/entry/115440)</td></tr>
<tr><th>Ensembl</th><td>[ENSG00000101266](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000101266)</td></tr>
<tr><th>UniProt</th><td>[P68400](https://www.uniprot.org/uniprot/P68400)</td></tr>
<tr><th>Encoded Protein</th><td>[CK2α protein](/proteins/ck2-alpha-protein)</td></tr>
<tr><th>Associated Diseases</th><td>Alzheimer's disease, Parkinson's disease, Cancer, Okur-Chung syndrome</td></tr>
</table>
</div>
Overview
Mermaid diagram (expand to render)
CSNK2A1 (Casein Kinase 2 Alpha 1) encodes the catalytic alpha subunit of casein kinase 2 (CK2), a constitutively active serine/threonine kinase with over 300 known substrates.[@stahl2021] CK2 plays critical roles in [tau](/proteins/tau) phosphorylation, NMDA receptor modulation, neuroinflammation, and neuronal survival pathways.[@lebrin2005] In neurodegeneration, CK2 hyperactivity contributes to pathological tau phosphorylation while also providing neuroprotection through anti-apoptotic signaling, creating a complex dual role in disease pathogenesis.
Gene Structure and Expression
The CSNK2A1 gene spans approximately 56 kb on chromosome 20p13 and contains 10 exons.[@wirkner1994] The encoded 350-amino acid protein forms the catalytic subunit that:
- Heterotetramer formation: Combines with regulatory β subunits (CSNK2B) to form α₂β₂ or αα'β₂ holoenzymes
- Constitutive activity: Unlike most kinases, CK2 is constitutively active without requiring phosphorylation
- Ubiquitous expression: High levels in brain, particularly in [neurons](/entities/neurons)
Expression in the nervous system: CK2α is highly expressed in [hippocampus](/brain-regions/hippocampus), [cortex](/brain-regions/cortex), and cerebellum. Activity increases in AD brains, correlating with neurofibrillary tangle burden.[@iimoto1990]
Function
CK2 Holoenzyme
CK2 exists as a heterotetramer (α₂β₂ or αα'β₂) with multiple functions:[@litchfield2003]
Catalytic activity: α and α' subunits provide kinase activity
Substrate recognition: β subunits modulate substrate specificity
Localization: β subunits regulate nuclear/cytoplasmic distribution
Stability: β subunits protect catalytic subunits from degradationTau Phosphorylation
CK2 phosphorylates tau at multiple sites:[@plotner2017]
- Ser202/Thr205: AT8 epitope (also GSK3β, [CDK5](/proteins/cdk5) targets)
- Ser396/Ser404: PHF-1 epitope
- Ser422: Disease-associated site
- Priming activity: CK2 can prime tau for subsequent GSK3β phosphorylation
NMDA Receptor Modulation
CK2 phosphorylates NMDA receptor subunits:[@lieberman1999]
- NR2B (GRIN2B): Ser1480 phosphorylation enhances channel function
- NR2A (GRIN2A): Modulates synaptic localization
- NMDA-mediated toxicity: CK2 inhibition reduces excitotoxicity
Neuroinflammation
CK2 regulates inflammatory signaling:[@ahmad2008]
- [NF-κB](/entities/nf-kb) pathway: Phosphorylates IκBα, promoting degradation
- TNF-α signaling: Modulates TNFR1 responses
- Microglial activation: CK2 activity increases in activated [microglia](/cell-types/microglia-neuroinflammation)
Disease Associations
Alzheimer's Disease
CK2 shows complex involvement in AD:[@rosenberger2016]
- Elevated activity: Increased CK2 activity in AD brains
- Tau pathology: CK2 phosphorylates tau at disease-relevant sites
- [Aβ](/proteins/amyloid-beta) interactions: CK2 phosphorylation affects [APP](/entities/app-protein) processing
- Neuroprotection: CK2 also activates survival pathways (AKT, NF-κB)
Parkinson's Disease
CK2 contributes to PD pathology:[@inglis2009]
- [α-synuclein](/proteins/alpha-synuclein) phosphorylation: CK2 phosphorylates Ser129
- Dopaminergic neuron vulnerability: CK2 inhibition reduces neuronal loss in models
- DJ-1 regulation: CK2 phosphorylates DJ-1, affecting its protective function
Okur-Chung Syndrome
De novo CSNK2A1 variants cause:[@okur2019]
- Neurodevelopmental disorder: Intellectual disability, developmental delay
- Features: Microcephaly, facial dysmorphism, skeletal anomalies
- Mechanism: Haploinsufficiency or dominant-negative effects
Expression Profile
| Tissue | Expression Level | Notes |
|--------|------------------|-------|
| Hippocampus | High | Tau phosphorylation, memory |
| Cerebral cortex | High | NMDA receptor regulation |
| Cerebellum | Moderate | Motor coordination |
| Microglia | Moderate | Increases with activation |
| [Astrocytes](/entities/astrocytes) | Moderate | Inflammatory signaling |
Common Variants
| Variant | dbSNP | Effect | Clinical Relevance |
|---------|-------|--------|-------------------|
| rs1008818 | NCBI | 3' UTR | Associated with AD risk in some cohorts |
| rs11552449 | NCBI | Intronic | Parkinson's disease association |
| rs2072554 | NCBI | Intronic | Cancer risk modifier |
Therapeutic Implications
CK2 Inhibitors for Neurodegeneration
CK2 inhibition as therapeutic strategy:[@chon2022]
CX-4945 (Silmitasertib): ATP-competitive inhibitor, in cancer trials
TBB (Tetrabromobenzotriazole): Classical CK2 inhibitor
CIGB-300: Peptide inhibitor targeting CK2 substratesChallenges
- Dual role: CK2 has both neurotoxic and neuroprotective functions
- Ubiquitous expression: Systemic inhibition affects many tissues
- Constitutive activity: Difficult to modulate physiologically
- [Blood-brain barrier](/entities/blood-brain-barrier): Need CNS-penetrant compounds
See Also
- [CSNK2A2 Gene](/genes/csnk2a2)
- [CSNK2B Gene](/genes/csnk2b)
- [Tau Pathology](/mechanisms/tau-pathology)
- [NMDA Receptor](/entities/nmda-receptor)
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's Disease](/diseases/parkinsons-disease)
External Links
- [GeneCards: CSNK2A1](https://www.genecards.org/cgi-bin/carddisp.pl?gene=CSNK2A1)
- [UniProt: P68400](https://www.uniprot.org/uniprot/P68400)
- [NCBI Gene: 1457](https://www.ncbi.nlm.nih.gov/gene/1457)
References
[Stahl M, et al, CK2: a protein kinase with a rich substrate repertoire (2021)](https://pubmed.ncbi.nlm.nih.gov/31806763/)
[Lebrin F, et al, CK2 and its role in neurodegenerative disease (2005)](https://pubmed.ncbi.nlm.nih.gov/16376232/)
[Wirkner U, et al, The gene encoding casein kinase II subunit alpha (1994)](https://pubmed.ncbi.nlm.nih.gov/8132632/)
[Iimoto DS, et al, Casein kinase II in Alzheimer's disease (1990)](https://pubmed.ncbi.nlm.nih.gov/2063862/)
[Litchfield DW, Protein kinase CK2: structure, regulation and role in cellular decisions (2003)](https://pubmed.ncbi.nlm.nih.gov/14622075/)
[Plotner B, et al, Phosphorylation of the microtubule-associated protein tau by CK2 (2017)](https://pubmed.ncbi.nlm.nih.gov/28616942/)
[Lieberman DN, Mody I, CK2 modulation of NMDA receptors (1999)](https://pubmed.ncbi.nlm.nih.gov/10218164/)
[Ahmad KA, et al, CK2 and NF-κB signaling in cancer and inflammation (2008)](https://pubmed.ncbi.nlm.nih.gov/18394552/)
[Rosenberger AFN, et al, CK2 in Alzheimer's disease pathology (2016)](https://pubmed.ncbi.nlm.nih.gov/27017866/)
[Inglis KJ, et al, CK2 phosphorylation of α-synuclein (2009)](https://pubmed.ncbi.nlm.nih.gov/19420260/)
[Okur V, et al, CSNK2A1 variants cause Okur-Chung neurodevelopmental syndrome (2019)](https://pubmed.ncbi.nlm.nih.gov/30341086/)
[Chon HJ, et al, CK2 inhibitors in cancer therapy (2022)](https://pubmed.ncbi.nlm.nih.gov/35858887/)Pathway Diagram
The following diagram shows the key molecular relationships involving CSNK2A1 Gene discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)