Polyglutamine Protein
Polyglutamine Protein - Related Videos
09:23
Effect of Fluorescent Proteins on Fusion Partners Using Polyglutamine Toxicity Assays in Yeast
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Cited by 1 •
2018
This article describes protocols to assess the effect of fluorescent proteins on the aggregation and toxicity of misfolded polyglutamine expansion for the rapid evaluation of a newly uncharacterized fluorescent protein in the context of fluorescent reporters.
09:06
Growth Assays to Assess Polyglutamine Toxicity in Yeast
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Cited by 3 •
2012
This manuscript describes three complementary protocols for assessing the toxicity of polyglutamine (polyQ)-expansion proteins in the yeast Saccharomyces cerevisiae. These protocols can easily be modified to monitor the toxicity of other misfolded proteins in yeast.
03:03
Fluorescent Reporter-Based Paralysis Assay: A Technique to Assess Age-Associated Progressive Formation of Polyglutamine Fluorescent Reporter and Associated Paralysis in Caenorhabditis elegans
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2025
This video demonstrates an in vivo imaging-based assay to determine proteostasis decline due to aging. The assay uses Caenorhabditis elegans expressing polyglutamine YFP-fusion protein in body wall muscles to measure the age-associated aggregation of polyglutamine and induction of proteotoxicity, leading to paralysis.
08:16
Caenorhabditis elegans as a Model System for Discovering Bioactive Compounds Against Polyglutamine-Mediated Neurotoxicity
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Cited by 7 •
2021
Here, we present a protocol to assess the neuroprotective activities of test compounds in Caenorhabditis elegans, including polyglutamine aggregation, neuronal death, and chemoavoidance behavior, as well as an exemplary integration of multiple phenotypes.
08:46
Green Fluorescent Protein-based Expression Screening of Membrane Proteins in Escherichia coli
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Cited by 34 •
2015
A streamlined approach to screening for the expression of recombinant membrane proteins in Escherichia coli based on fusion to green fluorescent protein is presented.
FAQs
Extra CAG repeats in the encoding DNA lengthen the glutamine tract in the resulting protein. Once the tract expands beyond its normal range, the altered sequence can affect folding and make aggregation more likely. These changes may overload or disturb protein-homeostasis systems, providing a molecular link between repeat expansion and cellular dysfunction.
Protein homeostasis refers to the systems that maintain proteins in suitable amounts and functional states. Expanded tracts can disrupt this balance by promoting misfolding and aggregation, which may interfere with normal cellular pathways. Examining this relationship helps biochemists connect an altered protein sequence to broader cellular impairment rather than treating aggregation as an isolated event.
The key biochemical contrast is not simply the presence or absence of glutamine, but tract length relative to its normal range. A tract that expands can alter folding behavior and increase aggregation, creating consequences that are not expected from the unexpanded sequence. This comparison helps explain why repeat length is central when analyzing polyglutamine-related cellular effects.
Researchers combine model systems with biochemical assays to follow how these proteins behave. The assays can track aggregation, while model systems help examine resulting cellular effects and potential modifiers of toxicity. Together, they provide complementary evidence: one emphasizes measurable protein behavior, and the other connects that behavior with biological consequences relevant to polyglutamine research.
Researchers use model systems and biochemical assays to identify factors that change the harmful effects associated with expanded proteins. A modifier may be recognized through altered aggregation or altered cellular impairment, depending on the assay and model. Finding such modifiers can reveal pathways that influence toxicity and point toward possible therapeutic strategies.
Biochemical study links sequence expansion to changes in folding, aggregation, protein homeostasis, and cellular pathways. These molecular effects provide context for inherited disorders such as Huntington disease and several spinocerebellar ataxias, where neuronal impairment is especially important. The same framework supports testing disease mechanisms and assessing whether an intervention changes aggregation or toxicity.