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Induced expression of expanded CGG RNA causes mitochondrial dysfunction in vivo
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting carriers of premutation forms of the FMR1 gene, resulting in a progressive development of tremor, ataxia and neuropsychological problems. The disease is caused by an expanded CGG repeat in the FM...
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Published in: | Cell cycle (Georgetown, Tex.) Tex.), 2014-08, Vol.13 (16), p.2600-2608 |
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creator | Hukema, Renate K Buijsen, Ronald Am Raske, Chris Severijnen, Lies Anne Nieuwenhuizen-Bakker, Ingeborg Minneboo, Michelle Maas, Alex de Crom, Rini Kros, Johan M Hagerman, Paul J Berman, Robert F Willemsen, Rob |
description | Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting carriers of premutation forms of the FMR1 gene, resulting in a progressive development of tremor, ataxia and neuropsychological problems. The disease is caused by an expanded CGG repeat in the FMR1 gene, leading to an RNA gain-of-function toxicity mechanism. In order to study the pathogenesis of FXTAS, new inducible transgenic mouse models have been developed that expresses either 11CGGs or 90CGGs at the RNA level under control of a Tet-On promoter. When bred to an hnRNP-rtTA driver line, doxycycline (dox) induced expression of the transgene could be found in almost all tissues. Dox exposure resulted in loss of weight and death within 5 d for the 90CGG RNA expressing mice. Immunohistochemical examination of tissues of these mice revealed steatosis and apoptosis in the liver. Decreased expression of GPX1 and increased expression of cytochrome C is found. These effects were not seen in mice expressing a normal sized 11CGG repeat. In conclusion, we were able to show in vivo that expression of an expanded CGG-repeat rather than overexpression of a normal CGG-repeat causes pathology. In addition, we have shown that expanded CGG RNA expression can cause mitochondrial dysfunction by regulating expression levels of several markers. Although FTXAS patients do not display liver abnormalities, our findings contribute to understanding of the molecular mechanisms underlying toxicity of CGG repeat RNA expression in an animal model. In addition, the dox inducible mouse lines offer new opportunities to study therapeutic interventions for FXTAS. |
doi_str_mv | 10.4161/15384101.2014.943112 |
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The disease is caused by an expanded CGG repeat in the FMR1 gene, leading to an RNA gain-of-function toxicity mechanism. In order to study the pathogenesis of FXTAS, new inducible transgenic mouse models have been developed that expresses either 11CGGs or 90CGGs at the RNA level under control of a Tet-On promoter. When bred to an hnRNP-rtTA driver line, doxycycline (dox) induced expression of the transgene could be found in almost all tissues. Dox exposure resulted in loss of weight and death within 5 d for the 90CGG RNA expressing mice. Immunohistochemical examination of tissues of these mice revealed steatosis and apoptosis in the liver. Decreased expression of GPX1 and increased expression of cytochrome C is found. These effects were not seen in mice expressing a normal sized 11CGG repeat. In conclusion, we were able to show in vivo that expression of an expanded CGG-repeat rather than overexpression of a normal CGG-repeat causes pathology. In addition, we have shown that expanded CGG RNA expression can cause mitochondrial dysfunction by regulating expression levels of several markers. Although FTXAS patients do not display liver abnormalities, our findings contribute to understanding of the molecular mechanisms underlying toxicity of CGG repeat RNA expression in an animal model. In addition, the dox inducible mouse lines offer new opportunities to study therapeutic interventions for FXTAS.</description><identifier>ISSN: 1538-4101</identifier><identifier>EISSN: 1551-4005</identifier><identifier>DOI: 10.4161/15384101.2014.943112</identifier><identifier>PMID: 25486200</identifier><language>eng</language><publisher>United States: Taylor & Francis</publisher><subject>Animals ; Anti-Bacterial Agents - metabolism ; apoptosis ; Apoptosis - drug effects ; Ataxia - genetics ; Ataxia - metabolism ; caspase 3 ; CGG repeat ; cytochrome C ; Disease Models, Animal ; Doxycycline - metabolism ; Fatty Liver - pathology ; Fragile X Syndrome - genetics ; Fragile X Syndrome - metabolism ; FXTAS ; gpx-1 ; inducible mouse model ; Liver - metabolism ; Liver - ultrastructure ; Mice ; Mice, Transgenic ; mitochondria ; Mitochondria - drug effects ; Mitochondria - metabolism ; Promoter Regions, Genetic ; Reactive Oxygen Species ; Repetitive Sequences, Nucleic Acid - genetics ; RNA - genetics ; RNA - metabolism ; RNA gain-of-function ; Tet-On ; Tremor - genetics ; Tremor - metabolism</subject><ispartof>Cell cycle (Georgetown, Tex.), 2014-08, Vol.13 (16), p.2600-2608</ispartof><rights>2014 Taylor & Francis Group, LLC 2014</rights><rights>2014 Taylor & Francis Group, LLC 2014 Taylor & Francis Group, LLC</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c418t-20ebdcd252868b02827f1a6f26b38c102c30cd1fa8bbaf156547ad9be5405ac53</citedby><cites>FETCH-LOGICAL-c418t-20ebdcd252868b02827f1a6f26b38c102c30cd1fa8bbaf156547ad9be5405ac53</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC4614669/pdf/$$EPDF$$P50$$Gpubmedcentral$$H</linktopdf><linktohtml>$$Uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC4614669/$$EHTML$$P50$$Gpubmedcentral$$H</linktohtml><link.rule.ids>230,314,727,780,784,885,27924,27925,53791,53793</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/25486200$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Hukema, Renate K</creatorcontrib><creatorcontrib>Buijsen, Ronald Am</creatorcontrib><creatorcontrib>Raske, Chris</creatorcontrib><creatorcontrib>Severijnen, Lies Anne</creatorcontrib><creatorcontrib>Nieuwenhuizen-Bakker, Ingeborg</creatorcontrib><creatorcontrib>Minneboo, Michelle</creatorcontrib><creatorcontrib>Maas, Alex</creatorcontrib><creatorcontrib>de Crom, Rini</creatorcontrib><creatorcontrib>Kros, Johan M</creatorcontrib><creatorcontrib>Hagerman, Paul J</creatorcontrib><creatorcontrib>Berman, Robert F</creatorcontrib><creatorcontrib>Willemsen, Rob</creatorcontrib><title>Induced expression of expanded CGG RNA causes mitochondrial dysfunction in vivo</title><title>Cell cycle (Georgetown, Tex.)</title><addtitle>Cell Cycle</addtitle><description>Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting carriers of premutation forms of the FMR1 gene, resulting in a progressive development of tremor, ataxia and neuropsychological problems. The disease is caused by an expanded CGG repeat in the FMR1 gene, leading to an RNA gain-of-function toxicity mechanism. In order to study the pathogenesis of FXTAS, new inducible transgenic mouse models have been developed that expresses either 11CGGs or 90CGGs at the RNA level under control of a Tet-On promoter. When bred to an hnRNP-rtTA driver line, doxycycline (dox) induced expression of the transgene could be found in almost all tissues. Dox exposure resulted in loss of weight and death within 5 d for the 90CGG RNA expressing mice. Immunohistochemical examination of tissues of these mice revealed steatosis and apoptosis in the liver. Decreased expression of GPX1 and increased expression of cytochrome C is found. These effects were not seen in mice expressing a normal sized 11CGG repeat. In conclusion, we were able to show in vivo that expression of an expanded CGG-repeat rather than overexpression of a normal CGG-repeat causes pathology. In addition, we have shown that expanded CGG RNA expression can cause mitochondrial dysfunction by regulating expression levels of several markers. Although FTXAS patients do not display liver abnormalities, our findings contribute to understanding of the molecular mechanisms underlying toxicity of CGG repeat RNA expression in an animal model. In addition, the dox inducible mouse lines offer new opportunities to study therapeutic interventions for FXTAS.</description><subject>Animals</subject><subject>Anti-Bacterial Agents - metabolism</subject><subject>apoptosis</subject><subject>Apoptosis - drug effects</subject><subject>Ataxia - genetics</subject><subject>Ataxia - metabolism</subject><subject>caspase 3</subject><subject>CGG repeat</subject><subject>cytochrome C</subject><subject>Disease Models, Animal</subject><subject>Doxycycline - metabolism</subject><subject>Fatty Liver - pathology</subject><subject>Fragile X Syndrome - genetics</subject><subject>Fragile X Syndrome - metabolism</subject><subject>FXTAS</subject><subject>gpx-1</subject><subject>inducible mouse model</subject><subject>Liver - metabolism</subject><subject>Liver - ultrastructure</subject><subject>Mice</subject><subject>Mice, Transgenic</subject><subject>mitochondria</subject><subject>Mitochondria - drug effects</subject><subject>Mitochondria - metabolism</subject><subject>Promoter Regions, Genetic</subject><subject>Reactive Oxygen Species</subject><subject>Repetitive Sequences, Nucleic Acid - genetics</subject><subject>RNA - genetics</subject><subject>RNA - metabolism</subject><subject>RNA gain-of-function</subject><subject>Tet-On</subject><subject>Tremor - genetics</subject><subject>Tremor - metabolism</subject><issn>1538-4101</issn><issn>1551-4005</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2014</creationdate><recordtype>article</recordtype><recordid>eNp9kU9PGzEQxS1UBDTwDSq0x1429Xhtx7lQRVFJI0UgIThbXv8pRrt2au-G5tuzqwCiF062x7_3ZjQPoW-ApxQ4_ABWCQoYpgQDnc5pBUCO0BkwBiXFmH0Z75UoR-YUfc35CWMiZnM4QaeEUcEJxmfodh1Mr60p7L9tsjn7GIroxpcKZigvV6vi7mZRaNVnm4vWd1E_xmCSV01h9tn1QXejyIdi53fxHB071WR78XpO0MP1r_vl73Jzu1ovF5tSUxBdSbCtjTaEEcFFPcxFZg4Ud4TXldCAia6wNuCUqGvlgHFGZ8rMa8soZkqzaoKuDr7bvm6t0TZ0STVym3yr0l5G5eX_P8E_yj9xJykHyvl8MPj-apDi397mTrY-a9s0KtjYZwm8YhgLysSA0gOqU8w5WffeBrAcs5BvWcgxC3nIYpBdfhzxXfS2_AH4eQB8cDG16jmmxshO7ZuYXFJB-yyrT1u8AH5SmXE</recordid><startdate>20140818</startdate><enddate>20140818</enddate><creator>Hukema, Renate K</creator><creator>Buijsen, Ronald Am</creator><creator>Raske, Chris</creator><creator>Severijnen, Lies Anne</creator><creator>Nieuwenhuizen-Bakker, Ingeborg</creator><creator>Minneboo, Michelle</creator><creator>Maas, Alex</creator><creator>de Crom, Rini</creator><creator>Kros, Johan M</creator><creator>Hagerman, Paul J</creator><creator>Berman, Robert F</creator><creator>Willemsen, Rob</creator><general>Taylor & Francis</general><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7X8</scope><scope>5PM</scope></search><sort><creationdate>20140818</creationdate><title>Induced expression of expanded CGG RNA causes mitochondrial dysfunction in vivo</title><author>Hukema, Renate K ; Buijsen, Ronald Am ; Raske, Chris ; Severijnen, Lies Anne ; Nieuwenhuizen-Bakker, Ingeborg ; Minneboo, Michelle ; Maas, Alex ; de Crom, Rini ; Kros, Johan M ; Hagerman, Paul J ; Berman, Robert F ; Willemsen, Rob</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c418t-20ebdcd252868b02827f1a6f26b38c102c30cd1fa8bbaf156547ad9be5405ac53</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2014</creationdate><topic>Animals</topic><topic>Anti-Bacterial Agents - metabolism</topic><topic>apoptosis</topic><topic>Apoptosis - drug effects</topic><topic>Ataxia - genetics</topic><topic>Ataxia - metabolism</topic><topic>caspase 3</topic><topic>CGG repeat</topic><topic>cytochrome C</topic><topic>Disease Models, Animal</topic><topic>Doxycycline - metabolism</topic><topic>Fatty Liver - pathology</topic><topic>Fragile X Syndrome - genetics</topic><topic>Fragile X Syndrome - metabolism</topic><topic>FXTAS</topic><topic>gpx-1</topic><topic>inducible mouse model</topic><topic>Liver - metabolism</topic><topic>Liver - ultrastructure</topic><topic>Mice</topic><topic>Mice, Transgenic</topic><topic>mitochondria</topic><topic>Mitochondria - drug effects</topic><topic>Mitochondria - metabolism</topic><topic>Promoter Regions, Genetic</topic><topic>Reactive Oxygen Species</topic><topic>Repetitive Sequences, Nucleic Acid - genetics</topic><topic>RNA - genetics</topic><topic>RNA - metabolism</topic><topic>RNA gain-of-function</topic><topic>Tet-On</topic><topic>Tremor - genetics</topic><topic>Tremor - metabolism</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Hukema, Renate K</creatorcontrib><creatorcontrib>Buijsen, Ronald Am</creatorcontrib><creatorcontrib>Raske, Chris</creatorcontrib><creatorcontrib>Severijnen, Lies Anne</creatorcontrib><creatorcontrib>Nieuwenhuizen-Bakker, Ingeborg</creatorcontrib><creatorcontrib>Minneboo, Michelle</creatorcontrib><creatorcontrib>Maas, Alex</creatorcontrib><creatorcontrib>de Crom, Rini</creatorcontrib><creatorcontrib>Kros, Johan M</creatorcontrib><creatorcontrib>Hagerman, Paul J</creatorcontrib><creatorcontrib>Berman, Robert F</creatorcontrib><creatorcontrib>Willemsen, Rob</creatorcontrib><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>MEDLINE - Academic</collection><collection>PubMed Central (Full Participant titles)</collection><jtitle>Cell cycle (Georgetown, Tex.)</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Hukema, Renate K</au><au>Buijsen, Ronald Am</au><au>Raske, Chris</au><au>Severijnen, Lies Anne</au><au>Nieuwenhuizen-Bakker, Ingeborg</au><au>Minneboo, Michelle</au><au>Maas, Alex</au><au>de Crom, Rini</au><au>Kros, Johan M</au><au>Hagerman, Paul J</au><au>Berman, Robert F</au><au>Willemsen, Rob</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Induced expression of expanded CGG RNA causes mitochondrial dysfunction in vivo</atitle><jtitle>Cell cycle (Georgetown, Tex.)</jtitle><addtitle>Cell Cycle</addtitle><date>2014-08-18</date><risdate>2014</risdate><volume>13</volume><issue>16</issue><spage>2600</spage><epage>2608</epage><pages>2600-2608</pages><issn>1538-4101</issn><eissn>1551-4005</eissn><abstract>Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting carriers of premutation forms of the FMR1 gene, resulting in a progressive development of tremor, ataxia and neuropsychological problems. The disease is caused by an expanded CGG repeat in the FMR1 gene, leading to an RNA gain-of-function toxicity mechanism. In order to study the pathogenesis of FXTAS, new inducible transgenic mouse models have been developed that expresses either 11CGGs or 90CGGs at the RNA level under control of a Tet-On promoter. When bred to an hnRNP-rtTA driver line, doxycycline (dox) induced expression of the transgene could be found in almost all tissues. Dox exposure resulted in loss of weight and death within 5 d for the 90CGG RNA expressing mice. Immunohistochemical examination of tissues of these mice revealed steatosis and apoptosis in the liver. Decreased expression of GPX1 and increased expression of cytochrome C is found. These effects were not seen in mice expressing a normal sized 11CGG repeat. In conclusion, we were able to show in vivo that expression of an expanded CGG-repeat rather than overexpression of a normal CGG-repeat causes pathology. In addition, we have shown that expanded CGG RNA expression can cause mitochondrial dysfunction by regulating expression levels of several markers. Although FTXAS patients do not display liver abnormalities, our findings contribute to understanding of the molecular mechanisms underlying toxicity of CGG repeat RNA expression in an animal model. In addition, the dox inducible mouse lines offer new opportunities to study therapeutic interventions for FXTAS.</abstract><cop>United States</cop><pub>Taylor & Francis</pub><pmid>25486200</pmid><doi>10.4161/15384101.2014.943112</doi><tpages>9</tpages><oa>free_for_read</oa></addata></record> |
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subjects | Animals Anti-Bacterial Agents - metabolism apoptosis Apoptosis - drug effects Ataxia - genetics Ataxia - metabolism caspase 3 CGG repeat cytochrome C Disease Models, Animal Doxycycline - metabolism Fatty Liver - pathology Fragile X Syndrome - genetics Fragile X Syndrome - metabolism FXTAS gpx-1 inducible mouse model Liver - metabolism Liver - ultrastructure Mice Mice, Transgenic mitochondria Mitochondria - drug effects Mitochondria - metabolism Promoter Regions, Genetic Reactive Oxygen Species Repetitive Sequences, Nucleic Acid - genetics RNA - genetics RNA - metabolism RNA gain-of-function Tet-On Tremor - genetics Tremor - metabolism |
title | Induced expression of expanded CGG RNA causes mitochondrial dysfunction in vivo |
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