Aberrant folding of proteins is a feature comnnon to many neurodegenerative diseases, including prion disease, Huntington's disease (HD), Alzheimer's disease, and others. Misfolded proteins may adopt several distinct tertiary and quaternary conformations, both in terms of their stable, end states, and in terms of meta-stable intermediate states they acquire as they progress from monomers to large aggregated protein deposits in the brain. Identification of specific protein conformations involved in disease processes is lacking for many neurodegenerative diseases, although we have made progress in this regard for prion disease during the mentored phase ofthis award (Colby et.al., PNAS 2009;Colby etal., PLoS Pathog. 2010). We have begun to elucidate the manner in which biophysical properties of misfolded proteins correlate to and even directly result in specific disease phenotypes. in HD however, the role of misfolded proteins in pathogenesis is controversial and much work remains to be done to establish the conformational basis of this disease. In the independent phase of this award, we will apply the same approaches we have leamed over the past several years studying prion disease to HD in order to identify specific conformations ofthe huntingtin protein that result in neurodegeneration. Using peptides, recombinant protein, and misfolded proteins isolated from laboratory animal models and cell culture models, as well as HD patients, we will assess the extent to which the huntingtin protein is capable of acquiring diverse conformations. We will then determine if any of these conformations are capable of initiating neural death or dysfunction in cell and animal models. In a complementary approach, we will also devielop a technique for detecting misfolded huntingtin based on the propensity of misfolded proteins to nucleate or 'seed'amyloid formation. An analogous assay for detecting prions had femtogram sensitivity (Colby et. al., PNAS, 2007). The ability to sensitively detect misfolded huntingtin will enable us to identify its presence much earlier in disease progression than is currently possible. A better understanding ofthe molecular basis of Huntington's disease and related neurodegenerative disorders shall aid substantially in the search for a cure.

Public Health Relevance

The proposed research seeks to understand the cause of a hereditary neurodegerative disorder, Huntington's disease. The research may also impact Alzheimer's disease and Parkinson's disease research, because these diseases are likely to have common causes.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Transition Award (R00)
Project #
5R00NS064173-05
Application #
8286425
Study Section
Special Emphasis Panel (NSS)
Program Officer
Wong, May
Project Start
2009-01-01
Project End
2013-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
5
Fiscal Year
2012
Total Cost
$207,971
Indirect Cost
$72,042
Name
University of Delaware
Department
Engineering (All Types)
Type
Schools of Engineering
DUNS #
059007500
City
Newark
State
DE
Country
United States
Zip Code
19716
Morozova, Olga A; Gupta, Sharad; Colby, David W (2015) Prefibrillar huntingtin oligomers isolated from HD brain potently seed amyloid formation. FEBS Lett 589:1897-903
Doolan, Kyle M; Colby, David W (2015) Conformation-dependent epitopes recognized by prion protein antibodies probed using mutational scanning and deep sequencing. J Mol Biol 427:328-40
Barbaro, Brett A; Lukacsovich, Tamas; Agrawal, Namita et al. (2015) Comparative study of naturally occurring huntingtin fragments in Drosophila points to exon 1 as the most pathogenic species in Huntington's disease. Hum Mol Genet 24:913-25
Watts, Joel C; Giles, Kurt; Patel, Smita et al. (2014) Evidence that bank vole PrP is a universal acceptor for prions. PLoS Pathog 10:e1003990
Morozova, Olga A; March, Zachary M; Robinson, Anne S et al. (2013) Conformational features of tau fibrils from Alzheimer's disease brain are faithfully propagated by unmodified recombinant protein. Biochemistry 52:6960-7
Gupta, Sharad; Jie, Shy'Ann; Colby, David W (2012) Protein misfolding detected early in pathogenesis of transgenic mouse model of Huntington disease using amyloid seeding assay. J Biol Chem 287:9982-9
Colby, David W; Wain, Rachel; Baskakov, Ilia V et al. (2010) Protease-sensitive synthetic prions. PLoS Pathog 6:e1000736
Colby, David W; Giles, Kurt; Legname, Giuseppe et al. (2009) Design and construction of diverse mammalian prion strains. Proc Natl Acad Sci U S A 106:20417-22