# Identification and Analysis of Axolotl Homologs for Proteins Implicated in Human Neurodegenerative Proteinopathies

## TL;DR

This paper explores whether axolotls, known for their brain regeneration, have proteins similar to those involved in human neurodegenerative diseases like Alzheimer's, suggesting they could help study disease mechanisms and regeneration.

## Contribution

The study identifies and validates homologs of human disease-related proteins in axolotls, suggesting their potential use in neurodegenerative disease research.

## Key findings

- Axolotls encode proteins highly similar to human tau, APP, and BACE1, which are linked to Alzheimer's Disease.
- Monoclonal Tau and BACE1 antibodies used in human studies also recognize axolotl proteins, validating homology.
- Axolotls may serve as a model to study neuroresilience and repair in the context of proteinopathies.

## Abstract

Neurodegenerative proteinopathies such as Alzheimer’s Disease are characterized by abnormal protein aggregation and neurodegeneration. Neuroresilience or regenerative strategies to prevent neurodegeneration, preserve function, or restore lost neurons may have the potential to combat human proteinopathies; however, the adult human brain possesses a limited capacity to replace lost neurons. In contrast, axolotls (Ambystoma mexicanum) show robust brain regeneration. To determine whether axolotls may help identify potential neuroresilience or regenerative strategies in humans, we first interrogated whether axolotls express putative proteins homologous to human proteins associated with neurodegenerative diseases. We compared the homology between human and axolotl proteins implicated in human proteinopathies and found that axolotls encode proteins highly similar to human microtubule-binding protein tau (tau), amyloid precursor protein (APP), and β-secretase 1 (BACE1), which are critically involved in human proteinopathies like Alzheimer’s Disease. We then tested monoclonal Tau and BACE1 antibodies previously used in human and rodent neurodegenerative disease studies using immunohistochemistry and western blotting to validate the homology for these proteins. These studies suggest that axolotls may prove useful in studying the role of these proteins in disease within the context of neuroresilience and repair.