Alzheimer's Disease Research
Alya R. Raphael, Ph.D.
Stanford, CA, United States
Title: Stress Granule Pathways in TDP-43 Toxicity
Non-Technical Title: The Role Of RNA Granules in Neurodegenerative Disease
Aaron Gitler, Ph.D.
Duration: July 1, 2012 - February 28, 2014
Award Type: Postdoctoral Fellowship
Award Amount: $100,000
Alzheimer's disease and related neurodegenerative disease are devastating diseases that affect millions of people each year and have enormous societal costs. The pathology of many of these diseases involves the formation of insoluble protein aggregates, although whether these aggregates are the cause or result of disease is unknown. TDP-43, and the related protein FUS, are found aggregated in several neurodegenerative diseases. Understanding the biology behind their pathology may point to new treatment strategies.
Dr. Raphael's grant terminated when she assumed a new position at her institution.
The goal of these experiments is to understand how certain structures within the cell, called stress granules, contribute to several neurodegenerative diseases.
To study this, the researchers will first disturb these structures in a yeast model and ask how this affects the toxicity caused by accumulation of neurodegenerative disease proteins. Yeast is a simple experimental system often used in studies of cell biology. By capitalizing on a tremendous understanding of their genetics, and their (relatively) simple single-celled life cycle, previous yeast studies have lead to powerful advances in many areas of human biology.
The second part of this research study asks if stress granule components are improperly localized in human neurodegenerative disease samples, which would suggest that they play a role in human disease.
Finally, the experiments aim to identify previously unknown components of stress granules by screening many thousands of genes. Identifying new stress granule components will allow the new genes to be tested for involvement in the disease.
Apart from the focus on stress granules and their recent implication in neurodegeneration, this proposal is distinct from others in the field, in its leverage of the yeast model system's power and speed. Rather than limit the findings to yeast, this proposal also provides for experiments specifically designed to translate findings from yeast to human biology. Finally, the scientists plan to introduce an innovative screening technique, which could easily be adapted to study many other disease situations and could be a very powerful research tool.
The foreseeable benefits to the general public are two-fold. First, this work has the potential to identify new disease genes, which would be of immeasurable benefit to treating and studying neurodegenerative diseases. Second, understanding how stress granules contribute to disease will hopefully point to new treatment strategies and avenues for research in Alzheimer's disease, as well as other human disorders.
Raphael AR, Couthouis J, Sakamuri S, Siskind C, Vogel H, Day JW, Gitler AD.
Congenital muscular dystrophy and generalized epilepsy caused by GMPPB mutations.
Brain Res. 2014 Apr 26. pii: S0006-8993(14)00576-9. doi:
10.1016/j.brainres.2014.04.028. [Epub ahead of print] PubMed PMID:
Couthouis J, Raphael AR, Siskind C, Findlay AR, Buenrostro JD, Greenleaf WJ,
Vogel H, Day JW, Flanigan KM, Gitler AD. Exome sequencing identifies a DNAJB6
mutation in a family with dominantly-inherited limb-girdle muscular dystrophy.
Neuromuscul Disord. 2014 May;24(5):431-5. doi: 10.1016/j.nmd.2014.01.014. Epub
2014 Feb 10. PubMed PMID: 24594375; PubMed Central PMCID:
Kim HJ, Raphael AR, LaDow ES, McGurk L, Weber RA, Trojanowski JQ, Lee VM,
Finkbeiner S, Gitler AD, Bonini NM. Therapeutic modulation of eIF2α
phosphorylation rescues TDP-43 toxicity in amyotrophic lateral sclerosis disease
models. Nat Genet. 2014 Feb;46(2):152-60. doi: 10.1038/ng.2853. Epub 2013 Dec 15.
PubMed PMID: 24336168; PubMed Central PMCID:
Dr. Raphael is a postdoctoral fellow at Stanford University. She joined Dr. Aaron Gitler's laboratory in 2011. Her research focuses on using yeast as a model system to study mechanisms of neurodegenerative diseases, including Alzheimer's disease and amyotrophic lateral sclerosis. Raphael completed her Ph.D. work in Dr. Talbot's lab, also at Stanford University, studying peripheral nervous system development in zebrafish. In addition to her BrightFocus award, Raphael also received a Howard Hughes Medical Institute postdoctoral teaching fellowship, which allowed her to serve as a visiting assistant professor at Haverford College.