Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model
Huntington’s disease is a neurodegenerative disorder resulting from expansion of a polyglutamine tract in the Huntingtin protein. Mutant Huntingtin forms intracellular aggregates within neurons, although it is unclear whether aggregates or more soluble forms of the protein represent the pathogenic s...
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Genetics Society of America, The
2014
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| Online Access: | http://hdl.handle.net/1721.1/85583 https://orcid.org/0000-0001-5576-2887 |
| _version_ | 1826207122890686464 |
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| author | Kimura, Yoko Lee, Wyan-Ching Mimi Littleton, J. Troy Weiss, Kurt Richard |
| author2 | Massachusetts Institute of Technology. Department of Biology |
| author_facet | Massachusetts Institute of Technology. Department of Biology Kimura, Yoko Lee, Wyan-Ching Mimi Littleton, J. Troy Weiss, Kurt Richard |
| author_sort | Kimura, Yoko |
| collection | MIT |
| description | Huntington’s disease is a neurodegenerative disorder resulting from expansion of a polyglutamine tract in the Huntingtin protein. Mutant Huntingtin forms intracellular aggregates within neurons, although it is unclear whether aggregates or more soluble forms of the protein represent the pathogenic species. To examine the link between aggregation and neurodegeneration, we generated Drosophila melanogaster transgenic strains expressing fluorescently tagged human huntingtin encoding pathogenic (Q138) or nonpathogenic (Q15) proteins, allowing in vivo imaging of Huntingtin expression and aggregation in live animals. Neuronal expression of pathogenic Huntingtin leads to pharate adult lethality, accompanied by formation of large aggregates within the cytoplasm of neuronal cell bodies and neurites. Live imaging and Fluorescence Recovery After Photobleaching (FRAP) analysis of pathogenic Huntingtin demonstrated that new aggregates can form in neurons within 12 hr, while preexisting aggregates rapidly accumulate new Huntingtin protein within minutes. To examine the role of aggregates in pathology, we conducted haplo-insufficiency suppressor screens for Huntingtin-Q138 aggregation or Huntingtin-Q138–induced lethality, using deficiencies covering ~80% of the Drosophila genome. We identified two classes of interacting suppressors in our screen: those that rescue viability while decreasing Huntingtin expression and aggregation and those that rescue viability without disrupting Huntingtin aggregation. The most robust suppressors reduced both soluble and aggregated Huntingtin levels, suggesting toxicity is likely to be associated with both forms of the mutant protein in Huntington’s disease. |
| first_indexed | 2024-09-23T13:44:28Z |
| format | Article |
| id | mit-1721.1/85583 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T13:44:28Z |
| publishDate | 2014 |
| publisher | Genetics Society of America, The |
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| spelling | mit-1721.1/855832022-10-01T16:49:54Z Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model Kimura, Yoko Lee, Wyan-Ching Mimi Littleton, J. Troy Weiss, Kurt Richard Massachusetts Institute of Technology. Department of Biology Massachusetts Institute of Technology. Department of Brain and Cognitive Sciences Picower Institute for Learning and Memory Littleton, Troy Weiss, Kurt R. Kimura, Yoko Lee, Wyan-Ching Mimi Littleton, J. Troy Huntington’s disease is a neurodegenerative disorder resulting from expansion of a polyglutamine tract in the Huntingtin protein. Mutant Huntingtin forms intracellular aggregates within neurons, although it is unclear whether aggregates or more soluble forms of the protein represent the pathogenic species. To examine the link between aggregation and neurodegeneration, we generated Drosophila melanogaster transgenic strains expressing fluorescently tagged human huntingtin encoding pathogenic (Q138) or nonpathogenic (Q15) proteins, allowing in vivo imaging of Huntingtin expression and aggregation in live animals. Neuronal expression of pathogenic Huntingtin leads to pharate adult lethality, accompanied by formation of large aggregates within the cytoplasm of neuronal cell bodies and neurites. Live imaging and Fluorescence Recovery After Photobleaching (FRAP) analysis of pathogenic Huntingtin demonstrated that new aggregates can form in neurons within 12 hr, while preexisting aggregates rapidly accumulate new Huntingtin protein within minutes. To examine the role of aggregates in pathology, we conducted haplo-insufficiency suppressor screens for Huntingtin-Q138 aggregation or Huntingtin-Q138–induced lethality, using deficiencies covering ~80% of the Drosophila genome. We identified two classes of interacting suppressors in our screen: those that rescue viability while decreasing Huntingtin expression and aggregation and those that rescue viability without disrupting Huntingtin aggregation. The most robust suppressors reduced both soluble and aggregated Huntingtin levels, suggesting toxicity is likely to be associated with both forms of the mutant protein in Huntington’s disease. 2014-03-10T17:52:56Z 2014-03-10T17:52:56Z 2011-11 2011-08 Article http://purl.org/eprint/type/JournalArticle 0016-6731 http://hdl.handle.net/1721.1/85583 Weiss, K. R., Y. Kimura, W.-C. M. Lee, and J. T. Littleton. “Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington’s Disease Model.” Genetics 190, no. 2 (February 1, 2012): 581–600. https://orcid.org/0000-0001-5576-2887 en_US http://dx.doi.org/10.1534/genetics.111.133710 Genetics Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Genetics Society of America, The Littleton |
| spellingShingle | Kimura, Yoko Lee, Wyan-Ching Mimi Littleton, J. Troy Weiss, Kurt Richard Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model |
| title | Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model |
| title_full | Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model |
| title_fullStr | Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model |
| title_full_unstemmed | Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model |
| title_short | Huntingtin Aggregation Kinetics and Their Pathological Role in a Drosophila Huntington's Disease Model |
| title_sort | huntingtin aggregation kinetics and their pathological role in a drosophila huntington s disease model |
| url | http://hdl.handle.net/1721.1/85583 https://orcid.org/0000-0001-5576-2887 |
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