Preprint
Hypothesis

An Amyloid Agnostic Reformulation of the Alzheimer’s Disease: The Long Gene Vulnerability Hypothesis

Altmetrics

Downloads

373

Views

381

Comments

0

This version is not peer-reviewed

Submitted:

20 August 2021

Posted:

23 August 2021

You are already at the latest version

Alerts
Abstract
Alzheimer’s disease (AD) is a genetically complex senile neurodegeneration with unknown etiology. The first gene discovered to be mutated in early-onset AD, the amyloid precursor protein (APP), has been widely assumed as a causal factor in the disease cascade due to its generation of Aβ species. APP has an evolutionarily conserved biological role and activates a signaling program with notable similarities to integrin—a cell adhesion receptor with a wide array of functions. Intriguingly, several AD genome-wide association study (GWAS) candidate genes, including the SHARPIN locus recently reported by us and others, influence signaling of the integrin pathway. Integrins are focal adhesion regulators and serve in nervous system development, synaptic plasticity, and Tau phosphorylation. These observations suggest that the function of APP probably goes beyond Aβ generation in AD. Aging—the strongest risk factor for AD—is associated with various clock-like events in cells. For instance, neurons are continuously impacted by stochastic ‘hits’ to their genomes in aging, in the forms of DNA damage, insertion-deletions, copy-number variations (CNVs) and other types of somatic mutations. DNA damage and somatic mutations can result in neoplastic changes and cancer in mitotically active cells. However, their consequences in post-mitotic cells such as aging neurons are less defined. The current hypothesis holds that the stochastic loss of DNA sequence data at random loci in aging affects longer genes by chance more frequently. As a result, the biological processes coordinated by long genes may be more vulnerable to such random aging effects. Curiously, as shown by us and others, long genes are strongly enriched for synapse- and cell adhesion-related ontologies, more than any other biological process or cellular compartment. In addition, among various cell types, neurons possess the highest levels of long gene expression and are therefore more vulnerable to such harmful effects. The long gene vulnerability hypothesis provides a simple link between aging and the genetic landscape of AD and warrants new strategies for disease modification.
Keywords: 
Subject: Medicine and Pharmacology  -   Neuroscience and Neurology
Copyright: This open access article is published under a Creative Commons CC BY 4.0 license, which permit the free download, distribution, and reuse, provided that the author and preprint are cited in any reuse.
Prerpints.org logo

Preprints.org is a free preprint server supported by MDPI in Basel, Switzerland.

Subscribe

© 2024 MDPI (Basel, Switzerland) unless otherwise stated