{"id":566,"date":"2019-06-02T16:54:51","date_gmt":"2019-06-02T08:24:51","guid":{"rendered":"http:\/\/metabolismcompoundlibrary.com\/?p=566"},"modified":"2022-01-13T18:12:53","modified_gmt":"2022-01-13T09:42:53","slug":"mjd-arise-aberrant-expansion-polyglutamine-encoding-cag-repeat-ataxin3","status":"publish","type":"post","link":"http:\/\/metabolismcompoundlibrary.com\/index.php\/2019\/06\/02\/mjd-arise-aberrant-expansion-polyglutamine-encoding-cag-repeat-ataxin3\/","title":{"rendered":"In MJD and arise through aberrant expansion of the polyglutamine encoding CAG repeat within the ataxin3"},"content":{"rendered":"<p>Following destabilization of native protein folding by expanded polyglutamine domains, <img src=\"http:\/\/www.abmole.com\/upload\/structure\/Ambrisentan-chemical-structure.gif\" align=\"left\" width=\"207\" style=\"padding:10px;\"\/>the aggregation of mutant huntingtin or ataxin-3 proceeds by nucleated growth polymerization into protein fibrils that structurally resemble amyloid fibrils and react with amyloid-specific histochemical dyes such as Congo Red or thioflavin. Analogous biophysical properties are observed for b-amyloid and a-synuclein fibrils associated with Alzheimer\ufffd\ufffds and Parkinson\ufffd\ufffds diseases, respectively. Amyloid fibrils are thought to be nucleated by monomers or globular oligomers of misfolded protein. In turn, fibrils may co-assemble into much larger insoluble protein aggregates that are resistant to proteolysis. While it is clear that protein misfolding can elicit cellular toxicity, whether fibrillar protein aggregates are <a href=\"http:\/\/www.abmole.com\/products\/folinic-acid-calcium-salt-pentahydrate.html\">Folinic acid calcium salt pentahydrate<\/a> themselves toxic remains the subject of intense debate. On one hand, a growing body of evidence supports the &#8220;toxic soluble precursor&#8221; hypothesis in which end-stage protein fibrils are increasingly considered benign or even cytoprotective. In support of this hypothesis, small molecules that visibly stimulate inclusion-formation inside cells appear to be beneficial. However, contrasting studies have achieved <a href=\"http:\/\/www.abmole.com\/products\/ginsenoside-f2.html\">Ginsenoside-F2<\/a> compelling cytoprotection by preventing fibrils and aggregates from forming at all. These competing hypotheses are not mutually exclusive given the growing diversity in &#8220;onpathway&#8221; and &#8220;off-pathway&#8221; protein folding conformations observed during amyloidogenesis. Conventional antibodies raised against amyloid conformations are known to cross-react with a wide variety of misfolded proteins, thereby illustrating that diverse amyloidogenic proteins share isomorphic features. However, these conformation-specific antibodies cannot be readily implemented inside living cells to investigate the conformational toxicity of intracellular amyloidogenic proteins such as huntingtin, a-synuclein, and ataxin-3 in situ. In an alternative approach, recombinant single-chain Fv antibodies, which preserve the binding specificities of monoclonal antibodies within the framework of a single small polypeptide, can be selected in vitro and expressed intracellularly as &#8220;intrabodies&#8221; to probe huntingtin and a-synuclein in living cells. By encoding the antigen-binding site of an immunoglobulin within the framework of a single nucleic acid coding sequence, scFvs are amenable .<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Following destabilization of native protein folding by expanded polyglutamine domains, the aggregation of mutant huntingtin or ataxin-3 proceeds by nucleated growth polymerization into protein fibrils that structurally resemble amyloid fibrils and react with amyloid-specific histochemical dyes such as Congo Red or thioflavin. Analogous biophysical properties are observed for b-amyloid and a-synuclein fibrils associated with Alzheimer\ufffd\ufffds [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/566"}],"collection":[{"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/comments?post=566"}],"version-history":[{"count":1,"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/566\/revisions"}],"predecessor-version":[{"id":567,"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/566\/revisions\/567"}],"wp:attachment":[{"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/media?parent=566"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/categories?post=566"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/metabolismcompoundlibrary.com\/index.php\/wp-json\/wp\/v2\/tags?post=566"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}