Presenilin 1

Presenilin 1
Name	Presenilin 1
Uniprot	P49768
Length	467 aa
Location	Endoplasmic reticulum/Golgi apparatus membrane
Function	Catalytic subunit of γ-secretase complex; intramembrane aspartyl protease

Presenilin 1 is a multi-pass transmembrane protein that serves as the catalytic core of the γ-secretase complex and plays a central role in intramembrane proteolysis of type I membrane proteins. Identified in genetic studies of familial neurodegenerative disease, it has been studied alongside figures and institutions such as Alzheimer's Disease Research Center, Stanley B. Prusiner, and research groups at Massachusetts Institute of Technology and University College London. PSEN1 mutations were first linked to early-onset familial Alzheimer's disease in studies involving investigators from Mayo Clinic and National Institutes of Health.

Introduction

Presenilin 1 was discovered through linkage and positional cloning efforts involving investigators at University of Toronto, Cold Spring Harbor Laboratory, and Cambridge University that investigated pedigrees with autosomal dominant early-onset neurodegeneration. Subsequent biochemical and structural work by laboratories at Harvard University, University of California, San Francisco, and Max Planck Society established its role as the proteolytic engine of the γ-secretase complex, a finding cited in reviews by groups at Columbia University, Johns Hopkins University, and the Wellcome Trust. Its clinical relevance propelled collaborations with pharmaceutical companies such as Pfizer, Eli Lilly and Company, and AstraZeneca to target γ-secretase for therapeutic modulation.

Structure and molecular function

Presenilin 1 is a polytopic membrane protein of approximately 467 amino acids localized to the endoplasmic reticulum and Golgi apparatus membranes, with nine predicted transmembrane domains inferred from topology studies from labs at Salk Institute and Rockefeller University. High-resolution cryo-electron microscopy structures reported by consortia including European Molecular Biology Laboratory and Brookhaven National Laboratory revealed an active site comprising two conserved aspartate residues that align with mechanistic models from enzymology groups at University of Cambridge and ETH Zurich. Biochemical characterization by researchers at Stanford University and University of Pennsylvania demonstrated that presenilin undergoes endoproteolytic cleavage to form N-terminal and C-terminal fragments that assemble into a catalytic unit, consistent with protease paradigms elucidated by investigators at Max Planck Institute for Biophysical Chemistry.

Role in γ-secretase complex and APP processing

As the catalytic subunit of the γ-secretase complex, presenilin 1 associates with essential cofactors identified by teams at Cold Spring Harbor Laboratory and Dana-Farber Cancer Institute: nicastrin, APH1, and PEN-2. This complex mediates intramembrane cleavage of the amyloid precursor protein (APP), a process central to hypotheses developed by researchers at Alzheimer's Disease Research Center and debated in symposia at Society for Neuroscience meetings. Proteolysis of APP by γ-secretase follows ectodomain shedding by β-secretase (BACE1), generating amyloid-β peptides whose length distribution (Aβ40, Aβ42) was characterized in biochemical studies at National Institute on Aging and Imperial College London. Functional assays conducted at University of Toronto and Mount Sinai Hospital have linked altered cleavage specificity to changes in amyloidogenic peptide ratios implicated in neurodegeneration.

Genetics and mutations

Mutations in PSEN1 were identified in familial early-onset cases by consortia including investigators from Mayo Clinic, Massachusetts General Hospital, and University of Barcelona, with more than two hundred pathogenic variants cataloged through collaborations with Alzheimer's Disease Genetics Consortium and clinical centers at Kings College London. Classic studies involving pedigrees from Colombia and cohorts assembled by National Institutes of Health revealed autosomal dominant inheritance and variable penetrance patterns discussed in clinical guidelines from World Health Organization working groups. Genotype–phenotype correlations described by researchers at UCL Institute of Neurology and University of Pittsburgh indicate that specific missense substitutions can shift γ-secretase activity, accelerating disease onset in some families while producing atypical phenotypes in others.

Pathophysiology and Alzheimer's disease

Pathophysiological models linking presenilin 1 dysfunction to neurodegeneration were advanced by investigators at Alzheimer's Association conferences and laboratories at Yale School of Medicine and Columbia University, focusing on altered Aβ peptide production, impaired Notch signaling, and cellular stress pathways. Clinical-pathologic correlations from centers such as National Hospital for Neurology and Neurosurgery and Mayo Clinic associate PSEN1 mutations with early amyloid plaque deposition, cerebral amyloid angiopathy, and tau pathology described in studies from University College London and University of California, San Diego. Debates at European Academy of Neurology meetings have compared amyloid-centric hypotheses advanced by teams at Cold Spring Harbor Laboratory with alternative models emphasizing proteostasis and synaptic dysfunction explored at Scripps Research.

Expression, regulation, and interacting proteins

Expression analysis from transcriptomic consortia including Allen Institute for Brain Science and studies at Broad Institute report PSEN1 expression across multiple brain regions characterized by neuropathologists at Mayo Clinic and Massachusetts General Hospital. Regulatory mechanisms involving phosphorylation, ubiquitination, and exit from the endoplasmic reticulum were described by biochemical groups at Fred Hutchinson Cancer Research Center and University of Geneva, while proteomic screens from EMBL-EBI and ProteomeXchange identified interactors such as CD147 and components of trafficking machinery studied at Brigham and Women's Hospital and University of Oxford.

Animal models and therapeutic implications

Transgenic and knockout models developed at The Jackson Laboratory, European Molecular Biology Laboratory, and Riken have been instrumental in modeling PSEN1-linked pathology, informing pharmacological strategies pursued by teams at Biogen, Roche, and academic groups at Johns Hopkins University. Preclinical studies testing γ-secretase modulators, inhibitors, and substrate-specific approaches were presented at meetings of American Neurological Association and published by collaborations involving Harvard Medical School and UCSF Memory and Aging Center. These efforts continue amid regulatory discussions at agencies including Food and Drug Administration and European Medicines Agency about risk–benefit profiles for disease-modifying therapies.

Category:Proteins Category:Alzheimer's disease