A hallmark of most neurodegenerative diseases is the accumulation of toxic, misfolded proteins. A better understanding of how protein fate determination occurs may reveal novel therapeutic targets for degenerative brain diseases. While much has been learned about how the protein quality control system of neurons handles abnormal proteins, a major unresolved question remains: How is the determination to fold or degrade such proteins made by the chaperone and ubiquitin systems? The proposed studies will test the overall hypothesis that a specific E2 enzyme, Ube2w, regulates protein fate by rapidly monoubiquitinating misfolded proteins.
Aim 1 will employ Ube2w knockout mice and a mouse model of tauopathy to investigate Ube2w's predicted neuroprotective role in vivo.
Aim 2 will define the novel mechanism by which Ube2w rapidly attaches ubiquitin to substrates.
Aim 3 will seek to establish a direct correlation between the unfoldedness of a substrate protein and the attachment of ubiquitin by Ube2w and other E2s. Together these aims will help elucidate the role of Ube2w in degrading proteotoxic proteins and may provide insight into its role in countering neurotoxicity.

Public Health Relevance

The work proposed here will advance our understanding of how the ubiquitin and the chaperone systems collaborate to determine the fate of misfolded proteins. The work performed here may lead to novel drug targets and increase our understanding of how basic cellular pathways function to protect neurons from proteotoxic species.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Transition Award (R00)
Project #
4R00NS073936-03
Application #
8816449
Study Section
Special Emphasis Panel (NSS)
Program Officer
Sutherland, Margaret L
Project Start
2012-07-01
Project End
2017-03-31
Budget Start
2014-04-01
Budget End
2015-03-31
Support Year
3
Fiscal Year
2014
Total Cost
$249,000
Indirect Cost
$52,741
Name
Medical College of Wisconsin
Department
Biochemistry
Type
Schools of Medicine
DUNS #
937639060
City
Milwaukee
State
WI
Country
United States
Zip Code
53226
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