| Mutation Type |
Familial Alzheimer's Disease |
| Gene Affected |
PSEN1 (Presenilin-1) |
| Common Mutations |
M146V, L286V, A246E, H163R, A434C |
| Inheritance |
Autosomal Dominant |
| Disease |
Familial Alzheimer's Disease |
Psen1 Mutant Neurons plays an important role in the study of neurodegenerative diseases. This page provides comprehensive information about this topic, including its mechanisms, significance in disease processes, and therapeutic implications.
PSEN1-mutant neurons are neurons carrying pathogenic mutations in the Presenilin-1 gene (PSEN1), which encodes the catalytic core of the gamma-secretase complex. These mutations are the most common cause of autosomal dominant familial Alzheimer's disease (FAD), typically causing onset between 30-50 years of age. PSEN1 mutations account for approximately 50-70% of all FAD cases and over 300 pathogenic mutations have been identified in the gene.
Presenilin-1 is the catalytic subunit of the gamma-secretase complex, which cleaves amyloid precursor protein (APP) to generate amyloid-beta (Aβ) peptides. PSEN1 mutations lead to:
- Altered Aβ production: Most PSEN1 mutations shift the gamma-secretase cleavage pattern toward generating more aggregation-prone Aβ42 and Aβ43 species
- Reduced Aβ40 production: Some mutations decrease the production of the shorter, less toxic Aβ40
- Aβ42/40 ratio increase: The increased ratio of Aβ42 to Aβ40 is believed to accelerate amyloid plaque formation
Beyond amyloidogenesis, PSEN1 mutations affect:
- Calcium homeostasis: Dysregulation of endoplasmic reticulum calcium signaling
- Synaptic function: Impairment of long-term potentiation (LTP) and synaptic plasticity
- Autophagy: Disruption of lysosomal and autophagic pathways
- Mitochondrial function: Altered mitochondrial dynamics and energy metabolism
- Tau pathology: Enhanced tau phosphorylation and neurofibrillary tangle formation
PSEN1-mutant neurons derived from patient iPSCs or transgenic models exhibit:
- Increased Aβ42 secretion and extracellular Aβ deposition
- Enhanced tau phosphorylation and aggregation
- Synaptic deficits including reduced synaptic markers
- Mitochondrial dysfunction and oxidative stress
- Impaired calcium signaling
- Accelerated neuronal aging markers
| Feature |
PSEN1-Mutant Phenotype |
Normal Control |
| Aβ42/40 ratio |
Elevated (2-10x) |
Baseline |
| Tau phosphorylation |
Increased |
Baseline |
| Synaptic density |
Reduced |
Normal |
| Mitochondrial membrane potential |
Decreased |
Stable |
| Calcium homeostasis |
Dysregulated |
Regulated |
PSEN1 mutations cause early and prominent degeneration in:
- Hippocampus: CA1 region and entorhinal cortex are particularly vulnerable
- Cortex: Particularly in frontal and temporal regions
- Amygdala: Early tau pathology in basolateral nucleus
- Subcortical structures: Nucleus basalis of Meynert (cholinergic neurons)
- Gamma-secretase modulators: Developing compounds that shift cleavage toward Aβ40 production
- Anti-Aβ therapeutics: Immunotherapies targeting Aβ plaques and oligomers
- Gene therapy: Approaches to deliver wild-type PSEN1 or correct mutations
- Calcium stabilizers: Compounds to normalize calcium dysregulation
PSEN1-mutant neurons are associated with:
- Elevated cerebrospinal fluid Aβ42 levels (preclinical)
- Decreased CSF Aβ42 and increased tau (clinical)
- Earlier and more severe amyloid PET positivity
- Accelerated disease progression compared to sporadic AD
Patient-derived iPSC neurons carrying PSEN1 mutations provide valuable models for:
- Understanding disease mechanisms
- Drug screening platforms
- Personalized therapeutic approaches
Common mouse models include:
- APP/PS1 double transgenic: APPswe/PS1ΔE9
- 3xTg-AD: APPswe, PS1M146V, tauP301L
- 5xFAD: APPswe, I716F, PS1M146L, L286V
Psen1 Mutant Neurons plays an important role in the study of neurodegenerative diseases. This page provides comprehensive information about this topic, including its mechanisms, significance in disease processes, and therapeutic implications.
The study of Psen1 Mutant Neurons 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.
- Tandon et al., PSEN1 mutations in familial Alzheimer's disease (2000)
- Suzuki et al., iPSC models of PSEN1-mutant Alzheimer's disease (2013)
- Xia et al., PSEN1 mutations and gamma-secretase function (2015)
- Kelley et al., PSEN1 mutation effects on neuronal function (2017)
- Mertens et al., Direct reprogramming of PSEN1-mutant neurons (2020)
- Veugelen et al., Novel PSEN1 mutations and Aβ metabolism (2016)
- Szaruga et al., PSEN1 mutations alter Aβ pathophysiology (2015)
- Chávez-Gutiérrez et al., The mechanism of γ-secretase dysfunction (2012)