Angiotensin-Converting Enzyme (ACE) Protein
<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">ACE Protein</th>
</tr>
<tr>
<td class="label">
Protein Name</td>
<td>Angiotensin-Converting Enzyme</td>
</tr>
<tr>
<td class="label">
Gene</td>
<td>ACE</td>
</tr>
<tr>
<td class="label">
UniProt ID</td>
<td>P12821</td>
</tr>
<tr>
<td class="label">
PDB Structures</td>
<td>1O86, 1UZF, 2C6N</td>
</tr>
<tr>
<td class="label">
Molecular Weight</td>
<td>~170 kDa (somatic)</td>
</tr>
<tr>
<td class="label">
Subcellular Localization</td>
<td>Plasma membrane (type I transmembrane)</td>
</tr>
<tr>
<td class="label">
Protein Family</td>
<td>M2 metalloprotease family</td>
</tr>
<tr>
<td class="label">Tissue</td>
<td>Expression Level</td>
</tr>
<tr>
<td class="label">Lung endothelium</td>
<td>High</td>
</tr>
<tr>
<td class="label">Vascular endothelium</td>
<td>High</td>
</tr>
<tr>
<td class="label">Brain ([neurons](/entities/neurons), glia)</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Testis</td>
<td>Low</td>
</tr>
<tr>
<td class="label">Kidney</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Heart</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Drug Class</td>
<td>Examples</td>
</tr>
<tr>
<td class="label">ACE inhibitors</td>
<td>Captopril, Enalapril, Lisinopril</td>
</tr>
<tr>
<td class="label">Brain-penetrant ACE inhibi
...
Angiotensin-Converting Enzyme (ACE) Protein
<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">ACE Protein</th>
</tr>
<tr>
<td class="label">
Protein Name</td>
<td>Angiotensin-Converting Enzyme</td>
</tr>
<tr>
<td class="label">
Gene</td>
<td>ACE</td>
</tr>
<tr>
<td class="label">
UniProt ID</td>
<td>P12821</td>
</tr>
<tr>
<td class="label">
PDB Structures</td>
<td>1O86, 1UZF, 2C6N</td>
</tr>
<tr>
<td class="label">
Molecular Weight</td>
<td>~170 kDa (somatic)</td>
</tr>
<tr>
<td class="label">
Subcellular Localization</td>
<td>Plasma membrane (type I transmembrane)</td>
</tr>
<tr>
<td class="label">
Protein Family</td>
<td>M2 metalloprotease family</td>
</tr>
<tr>
<td class="label">Tissue</td>
<td>Expression Level</td>
</tr>
<tr>
<td class="label">Lung endothelium</td>
<td>High</td>
</tr>
<tr>
<td class="label">Vascular endothelium</td>
<td>High</td>
</tr>
<tr>
<td class="label">Brain ([neurons](/entities/neurons), glia)</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Testis</td>
<td>Low</td>
</tr>
<tr>
<td class="label">Kidney</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Heart</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Drug Class</td>
<td>Examples</td>
</tr>
<tr>
<td class="label">ACE inhibitors</td>
<td>Captopril, Enalapril, Lisinopril</td>
</tr>
<tr>
<td class="label">Brain-penetrant ACE inhibitors</td>
<td>Perindopril, Trandolapril</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/alzheimer" style="color:#ef9a9a">Alzheimer</a>, <a href="/wiki/cancer" style="color:#ef9a9a">Cancer</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">84 edges</a></td>
</tr>
</table>
Introduction
Ace Protein 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
Angiotensin-converting enzyme (ACE) is a zinc-dependent dipeptidyl carboxypeptidase that plays a central role in the renin-angiotensin system[@riordan2001]. The protein exists in two forms: somatic ACE (found in vascular endothelium) and germinal ACE (found in testis). ACE is a major therapeutic target for cardiovascular disease and has implications in neurodegenerative diseases[@kehoe2009]. Beyond its classical role in blood pressure regulation, ACE has been increasingly recognized for its roles in neuroinflammation, synaptic function, and cognitive processes.
Structure
ACE is a type I transmembrane glycoprotein with:
- Extracellular domain: Contains two homologous domains (N- and C-terminal), each with a zinc-binding HEXXH motif
- Single transmembrane helix: Anchors protein to plasma membrane
- Cytoplasmic tail: Short intracellular domain
Each catalytic domain can hydrolyze substrates independently, but the N-terminal domain is the primary site for angiotensin I conversion[@bernstein2005]. The two domains share 60% sequence homology but have distinct substrate specificities.
Normal Function
ACE catalyzes two important reactions:
Angiotensin I → Angiotensin II: Conversion of inactive decapeptide to active octapeptide vasoconstrictor
Bradykinin degradation: Inactivates vasodilatory bradykininKey functions:
- Blood pressure regulation through angiotensin II generation
- Electrolyte and fluid balance
- Vascular remodeling and fibrosis
- Inflammatory response modulation
- Neuropeptide metabolism in the brain
Angiotensin II Signaling
ACE-generated angiotensin II acts through two receptor subtypes:
- AT1R: Mediates most classical effects (vasoconstriction, aldosterone secretion, thirst)
- AT2R: Often has opposing effects (vasodilation, natriuresis, tissue protection)
Expression Pattern
ACE exhibits tissue-specific expression:
In the brain, ACE is expressed in:
- Cerebral [cortex](/brain-regions/cortex) (pyramidal neurons)
- [Hippocampus](/brain-regions/hippocampus) (CA1-CA3 regions)
- Basal ganglia
- [Hypothalamus](/brain-regions/hypothalamus)
- Choroid plexus
Molecular Mechanisms
Catalytic Mechanism
ACE uses a zinc-dependent mechanism:
. Zinc1 ion (Zn²⁺) coordinated by three histidine residues
Water molecule activated for nucleophilic attack
Peptide bond hydrolysis
Product releaseBrain-Specific Functions
In the central nervous system, ACE:
- Regulates neuronal excitability through angiotensin II
- Modulates synaptic plasticity and memory formation
- Controls neuroinflammation via [NF-κB](/entities/nf-kb) signaling
- Influences cerebral blood flow through vascular tone
Role in Disease
Alzheimer's Disease
- Elevated ACE activity in AD brains[@vardy2015]
- Angiotensin II promotes neuroinflammation through AT1R
- ACE I/D polymorphism affects AD risk and progression
- ACE inhibitors may provide neuroprotection through reduced Ang II signaling
- Studies show reduced [amyloid-beta](/proteins/amyloid-beta) pathology in ACE-inhibited mouse models
- Clinical observations suggest slower cognitive decline in ACE inhibitor users
Parkinson's Disease
- ACE polymorphisms influence PD susceptibility[@liu2017]
- Angiotensin II may affect dopaminergic neuron survival
- ACE inhibitors show potential neuroprotective effects in PD models
- The renin-angiotensin system intersects with dopamine metabolism
Stroke and Vascular Cognitive Impairment
- ACE contributes to vascular dysfunction
- ACE inhibition improves cerebral blood flow
- Reduces ischemic damage in experimental models
Amyotrophic Lateral Sclerosis (ALS)
- ACE activity elevated in ALS patients
- May contribute to excitotoxicity through bradykinin
- ACE inhibitors being explored as potential therapy
Therapeutic Targeting
Clinical Considerations
- Blood pressure effects: First-line concern in clinical use
- Cough: Most common side effect due to bradykinin accumulation
- Angioedema: Rare but serious adverse effect
- Combination therapy: Often with diuretics for enhanced effect
Research Directions
Novel Therapeutic Approaches
Selective AT2R agonists: Promote neuroprotective signaling
ACE2 activators: Increase angiotensin-(1-7) protective pathway
Dual ACE/NEP inhibitors: Enhance beneficial peptide generation
Brain-specific ACE inhibitors: Maximize CNS effectsBiomarker Potential
ACE activity is being explored as:
- Prognostic marker in AD progression
- Treatment response indicator
- Vascular dysfunction biomarker
Animal Models
Key findings from animal studies:
- ACE transgenic mice: Show increased Ang II and neuroinflammation
- ACE knockout mice: Protected from ischemic injury
- ACE inhibitor treated: Reduced amyloid pathology, improved cognition
Key Publications
<sup>[1]</sup> Riordan JF. Angiotensin-converting enzyme: from zinc metallopeptidase. Ann N Y Acad Sci. 2001;947:67-76. PMID: 11795238(https://pubmed.ncbi.nlm.nih.gov/11795238/)
<sup>[2]</sup> Kehoe PG, et al. Angiotensin-converting enzyme and Alzheimer's disease. Nat Rev Neurol. 2009;5(10):533-538. PMID: 19763147(https://pubmed.ncbi.nlm.nih.gov/19763147/)
<sup>[3]</sup> Bernstein KE, et al. A modern understanding of ACE. Am J Physiol. 2005;289(4):F613-621. PMID: 16143598(https://pubmed.ncbi.nlm.nih.gov/16143598/)
<sup>[4]</sup> Vardy ER, et al. ACE inhibitors and Alzheimer's disease. J Alzheimers Dis. 2015;45(2):377-387. PMID: 25537020(https://pubmed.ncbi.nlm.nih.gov/25537020/)
<sup>[5]</sup> Liu H, et al. ACE I/D polymorphism and Parkinson's disease. Neurol Sci. 2017;38(5):791-796. PMID: 28271282(https://pubmed.ncbi.nlm.nih.gov/28271282/)
<sup>[6]</sup> Jiang T, et al. Angiotensin-converting enzyme in neurodegeneration. Prog Neurobiol. 2022;208:102173. PMID: 35176482(https://pubmed.ncbi.nlm.nih.gov/35176482/)
<sup>[7]</sup> O'Dwyer G, et al. ACE and Alzheimer's disease. J Mol Neurosci. 2010;40(1-2):211-215. PMID: 20082152(https://pubmed.ncbi.nlm.nih.gov/20082152/)See Also
- [ACE Gene](/proteins/ace-protein)
- [Renin-Angiotensin System](/mechanisms/renin-angiotensin-system)
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's Disease](/diseases/parkinsons-disease)
- [Neuroinflammation Pathway](/mechanisms/neuroinflammation)
- [Angiotensin II Receptor](/entities/angiotensin-receptor)
External Links
- [ACE Protein - UniProt](https://www.uniprot.org/uniprot/P12821)
- [ACE Structure - PDB](https://www.rcsb.org/structure/1O86)
- [ACE Gene - NCBI](https://www.ncbi.nlm.nih.gov/gene/1636)
- [ClinicalTrials.gov - ACE inhibitors and dementia](https://clinicaltrials.gov)
Background
The study of Ace Protein 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.
Brain Atlas Resources
- [Allen Human Brain Atlas](https://human.brain-map.org/) — protein expression data
- [Allen Cell Type Atlas](https://celltypes.brain-map.org/) — cell type specific expression
- [BrainSpan Atlas](https://brainspan.org/) — developmental transcriptome
- [Allen Mouse Brain Atlas](https://mouse.brain-map.org/) — mouse brain expression
References
[Riordan JF, Angiotensin-converting enzyme: from zinc metallopeptidase (2001)](https://pubmed.ncbi.nlm.nih.gov/11795238/)
[Kehoe PG, et al, Angiotensin-converting enzyme and Alzheimer's disease (2009)](https://pubmed.ncbi.nlm.nih.gov/19763147/)
[Bernstein KE, et al, A modern understanding of ACE (2005)](https://pubmed.ncbi.nlm.nih.gov/16143598/)
[Vardy ER, et al, ACE inhibitors and Alzheimer's disease (2015)](https://pubmed.ncbi.nlm.nih.gov/25537020/)
[Liu H, et al, ACE I/D polymorphism and Parkinson's disease (2017)](https://pubmed.ncbi.nlm.nih.gov/28271282/)
[Jiang T, et al, Angiotensin-converting enzyme in neurodegeneration (2022)](https://pubmed.ncbi.nlm.nih.gov/35176482/)
[O'Dwyer G, et al, ACE and Alzheimer's disease (2010)](https://pubmed.ncbi.nlm.nih.gov/20082152/)From the [SciDEX Exchange](/exchange) — scored by multi-agent debate
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