PRKAA1

PRKAA1

<div class="infobox infobox-gene">
<h3>PRKAA1 (Protein Kinase AMP-Activated Catalytic Subunit Alpha 1)</h3>
<table>
<tr><td><strong>Full Name</strong></td><td>Protein Kinase AMP-Activated Catalytic Subunit Alpha 1 (AMPKα1)</td></tr>
<tr><td><strong>Gene Symbol</strong></td><td>PRKAA1</td></tr> [@zhu2019]
<tr><td><strong>Chromosomal Location</strong></td><td>5p13.1</td></tr> [@curry2018]
<tr><td><strong>NCBI Gene ID</strong></td><td>[5562](https://www.ncbi.nlm.nih.gov/gene/5562)</td></tr> [@steinberg2009]
<tr><td><strong>OMIM</strong></td><td>[602739](https://omim.org/entry/602739)</td></tr> [@marinangeli2016]
<tr><td><strong>Ensembl</strong></td><td>[ENSG00000132356](https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000132356)</td></tr> [@garcia2017]
<tr><td><strong>UniProt (Protein)</strong></td><td>[Q13131 (AMPKα1)](https://www.uniprot.org/uniprot/Q13131)</td></tr> [@lin2018]
<tr><td><strong>Associated Diseases</strong></td><td>[Alzheimer's Disease](/diseases/alzheimers-disease), [Parkinson's Disease](/diseases/parkinsons-disease), [ALS](/diseases/amyotrophic-lateral-sclerosis), [Huntington's Disease](/diseases/huntingtons-disease), Metabolic Syndrome</td></tr>
</table>
</div>

Pathway Diagram

PRKAA1

<div class="infobox infobox-gene">
<h3>PRKAA1 (Protein Kinase AMP-Activated Catalytic Subunit Alpha 1)</h3>
<table>
<tr><td><strong>Full Name</strong></td><td>Protein Kinase AMP-Activated Catalytic Subunit Alpha 1 (AMPKα1)</td></tr>
<tr><td><strong>Gene Symbol</strong></td><td>PRKAA1</td></tr> [@zhu2019]
<tr><td><strong>Chromosomal Location</strong></td><td>5p13.1</td></tr> [@curry2018]
<tr><td><strong>NCBI Gene ID</strong></td><td>[5562](https://www.ncbi.nlm.nih.gov/gene/5562)</td></tr> [@steinberg2009]
<tr><td><strong>OMIM</strong></td><td>[602739](https://omim.org/entry/602739)</td></tr> [@marinangeli2016]
<tr><td><strong>Ensembl</strong></td><td>[ENSG00000132356](https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000132356)</td></tr> [@garcia2017]
<tr><td><strong>UniProt (Protein)</strong></td><td>[Q13131 (AMPKα1)](https://www.uniprot.org/uniprot/Q13131)</td></tr> [@lin2018]
<tr><td><strong>Associated Diseases</strong></td><td>[Alzheimer's Disease](/diseases/alzheimers-disease), [Parkinson's Disease](/diseases/parkinsons-disease), [ALS](/diseases/amyotrophic-lateral-sclerosis), [Huntington's Disease](/diseases/huntingtons-disease), Metabolic Syndrome</td></tr>
</table>
</div>

Pathway Diagram

Overview

PRKAA1 (Protein Kinase AMP-Activated Catalytic Subunit Alpha 1) encodes the α1 catalytic subunit of AMP-activated protein kinase (AMPK), the master cellular energy sensor and metabolic regulator. AMPK is a heterotrimeric complex composed of a catalytic α subunit (PRKAA1/α1 or [PRKAA2](/genes/prkaa2)/α2), a scaffolding β subunit (PRKAB1/β1 or PRKAB2/β2), and a regulatory γ subunit (PRKAG1/γ1, PRKAG2/γ2, or PRKAG3/γ3). While the α2 subunit ([PRKAA2](/genes/prkaa2)) predominates in [neurons](/entities/neurons), the α1 subunit is the major isoform in [astrocytes](/cell-types/astrocytes), [microglia](/cell-types/microglia), [oligodendrocytes](/cell-types/oligodendrocytes), and brain endothelial cells, making PRKAA1 a critical regulator of glial metabolism, neuroinflammation, [blood-brain barrier](/entities/blood-brain-barrier) function, and myelination in the context of neurodegenerative disease.

Gene Structure and Expression

PRKAA1 spans approximately 65 kb on chromosome 5p13.1 and contains 10 exons encoding a 559 amino acid protein. The promoter region contains binding sites for CREB, SP1, and FOXO transcription factors. Unlike the highly regulated α2 subunit, PRKAA1/α1 is constitutively expressed across most tissues, reflecting its role as a ubiquitous metabolic sensor.

In the brain, PRKAA1/α1 shows a cell-type-specific expression pattern that is complementary to [PRKAA2](/genes/prkaa2)/α2. While α2 predominates in neurons, α1 is the dominant catalytic isoform in:

• [Astrocytes](/cell-types/astrocytes): AMPKα1 regulates astrocyte glycogen metabolism, lactate shuttle to neurons, and reactive astrogliosis
• [Microglia](/cell-types/microglia): AMPKα1 controls microglial metabolic reprogramming, phagocytosis, and inflammatory cytokine production
• [Oligodendrocytes](/cell-types/oligodendrocytes): AMPKα1 regulates lipid biosynthesis for myelination and oligodendrocyte maturation
• Brain endothelial cells: AMPKα1 maintains tight junction integrity and BBB function

Protein Function and Mechanism

AMPKα1 contains the following functional domains:

• Kinase domain (aa 27-279): Serine/threonine kinase domain with activation loop (T172) — the critical phosphorylation site for AMPK activation
• Autoinhibitory domain (AID) (aa 313-335): Intramolecular domain that suppresses kinase activity in the absence of AMP/ADP binding to the γ subunit
• α-linker (aa 336-395): Flexible linker connecting AID to the C-terminal regulatory domain; undergoes conformational change upon AMP binding to the γ subunit, relieving autoinhibition
• C-terminal domain (CTD/α-CTD) (aa 396-559): Mediates interaction with the β subunit and stabilizes the heterotrimeric complex

Key AMPKα1 substrates and functions in the CNS:

• ACC1/ACC2: Phosphorylation inhibits fatty acid synthesis and activates fatty acid oxidation — critical for oligodendrocyte lipid metabolism and microglial metabolic reprogramming
• ULK1 (S317, S555): Phosphorylation activates [autophagy](/entities/autophagy) initiation — AMPKα1 in [astrocytes](/entities/astrocytes) promotes autophagic clearance of protein aggregates
• [TFEB](/entities/tfeb) (S211): Phosphorylation promotes lysosomal biogenesis — glial aggregate clearance pathway
• mTORC1 (via TSC2/Raptor): AMPKα1 inhibits [mTOR](/mechanisms/mtor-signaling-pathway) signaling to reduce anabolic metabolism during energy stress
• [NF-κB](/entities/nf-kb) (p65 S536): AMPKα1 suppresses NF-κB inflammatory signaling in [microglia](/cell-types/microglia-neuroinflammation) and astrocytes
• HMGCR: Phosphorylation inhibits cholesterol synthesis — relevant to brain cholesterol homeostasis and ApoE metabolism

Disease Associations

Alzheimer's Disease

• Astrocyte metabolic failure: Reduced AMPKα1 activity impairs astrocyte glucose uptake and lactate production, starving neurons of metabolic support. AD astrocytes show diminished AMPK-dependent glycogen mobilization.
• Microglial dysfunction: AMPKα1 inactivation in [microglia](/cell-types/microglia) promotes the shift from oxidative phosphorylation to aerobic glycolysis (Warburg-like effect), driving pro-inflammatory M1 polarization and impairing [Aβ](/proteins/amyloid-beta) phagocytosis. Restoring AMPKα1 activity with metformin or AICAR promotes anti-inflammatory M2 polarization and enhances amyloid clearance.
• BBB breakdown: AMPKα1 inactivation in brain endothelial cells disrupts tight junction protein expression (claudin-5, occludin, ZO-1), contributing to BBB permeability observed in AD.
• Cholesterol dysregulation: AMPKα1-HMGCR axis disruption alters brain cholesterol homeostasis, affecting [ApoE](/proteins/apoe) lipidation and Aβ clearance.

Parkinson's Disease

• Microglial inflammation: [α-Synuclein](/proteins/alpha-synuclein) fibrils activate TLR2 on microglia, suppressing AMPKα1 and unleashing NF-κB-driven neuroinflammation. AMPKα1 activation with AICAR reduces pro-inflammatory cytokine production and nigral dopaminergic neuron loss in MPTP models.
• Astrocyte neuroprotection: AMPKα1 in astrocytes promotes secretion of neurotrophic factors ([GDNF](/genes/gdnf), [BDNF](/genes/bdnf)) and maintains the glutamate-glutamine cycle. AMPKα1 loss in astrocytes exacerbates excitotoxicity in PD.
• Oligodendrocyte dysfunction: AMPKα1 impairment reduces myelin lipid synthesis, contributing to white matter degeneration observed in PD.

ALS

• Astrocyte toxicity: SOD1-mutant astrocytes show reduced AMPKα1 activity, impaired autophagy of mutant SOD1 aggregates, and increased release of neurotoxic factors
• Microglial activation: AMPKα1 loss in microglia potentiates [TDP-43](/mechanisms/tdp-43-proteinopathy)-triggered neuroinflammation
• Oligodendrocyte degeneration: Early oligodendrocyte loss in ALS correlates with AMPKα1 inactivation and impaired myelination

Huntington's Disease

Common Variants

| Variant | Type | Clinical Significance |
|---------|------|----------------------|
| rs3805489 | Intronic SNP | GWAS association with type 2 diabetes risk |
| rs13361707 | 5' UTR | Associated with gastric cancer susceptibility |
| c.634G>A (p.Gly212Ser) | Missense | VUS, kinase domain |
| rs461404 | Intronic SNP | Associated with BMI in meta-analyses |
| c.1028T>C (p.Leu343Pro) | Missense | VUS, α-linker region |

Therapeutic Implications

AMPK activators are among the most studied neuroprotective compounds:

• Metformin: Indirect AMPK activator (via LKB1); epidemiological studies show reduced dementia risk in diabetic patients on metformin; clinical trials in AD and PD ongoing
• AICAR (acadesine): Cell-permeable AMP analog; activates AMPKα1/α2; anti-inflammatory in microglia but limited BBB penetration
• A-769662 and compound 991: Direct AMPKα1β1-selective activators; bind the ADaM (allosteric drug and metabolite) site at the α-β interface; improved isoform selectivity for glial-targeted activation
• Salicylate (aspirin metabolite): Direct AMPKα1β1 activator; epidemiological associations with reduced AD risk may partly reflect glial AMPK activation
• Trehalose: mTOR-independent autophagy inducer that also activates AMPK; promotes aggregate clearance in multiple neurodegenerative models
• Resveratrol: Indirect AMPK activator via SIRT1-LKB1 axis; neuroprotective in preclinical models but poor bioavailability limits clinical translation

See Also

• [PRKAA2](/genes/prkaa2) — AMPKα2 catalytic subunit, neuronal isoform
• [MTOR](/genes/mtor) — mTOR kinase, reciprocally regulated by AMPK
• [STK11](/genes/stk11) — LKB1, upstream AMPK kinase
• [LATS1](/genes/lats1) — Hippo pathway kinase, AMPK-Hippo crosstalk
• [LATS2](/genes/lats2) — Hippo pathway kinase, AMPK-Hippo crosstalk
• [SIRT1](/genes/sirt1) — AMPK-SIRT1 metabolic axis

External Links

• [NCBI Gene: PRKAA1](https://www.ncbi.nlm.nih.gov/gene/5562)
• [UniProt: Q13131](https://www.uniprot.org/uniprot/Q13131)
• [OMIM: 602739](https://omim.org/entry/602739)
• [GeneCards: PRKAA1](https://www.genecards.org/cgi-bin/carddisp.pl?gene=PRKAA1)
• [Allen Brain Atlas: PRKAA1](https://human.brain-map.org/)
• [PhosphoSitePlus: PRKAA1](https://www.phosphosite.org/proteinAction.action?id=3426)

References

Related Hypotheses

From the [SciDEX Exchange](/exchange) — scored by multi-agent debate

• [Digital Twin-Guided Metabolic Reprogramming](/hypothesis/h-b0cda336) — <span style="color:#81c784;font-weight:600">0.60</span> · Target: PPARGC1A/PRKAA1
• [AMPK hypersensitivity in astrocytes creates enhanced mitochondrial rescue responses](/hypothesis/h-43f72e21) — <span style="color:#ffd54f;font-weight:600">0.58</span> · Target: PRKAA1

Pathway Diagram

The following diagram shows the key molecular relationships involving PRKAA1 discovered through SciDEX knowledge graph analysis: