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pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking

BACKGROUND: Huntingtin (htt) is a multi-domain protein of 350 kDa that is mutated in Huntington's disease (HD) but whose function is yet to be fully understood. This absence of information is due in part to the difficulty of manipulating large DNA fragments by using conventional molecular cloni...

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Autores principales: Pardo, Raúl, Molina-Calavita, Maria, Poizat, Ghislaine, Keryer, Guy, Humbert, Sandrine, Saudou, Frédéric
Formato: Texto
Lenguaje:English
Publicado: BioMed Central 2010
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2887845/
https://www.ncbi.nlm.nih.gov/pubmed/20515468
http://dx.doi.org/10.1186/1756-6606-3-17
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author Pardo, Raúl
Molina-Calavita, Maria
Poizat, Ghislaine
Keryer, Guy
Humbert, Sandrine
Saudou, Frédéric
author_facet Pardo, Raúl
Molina-Calavita, Maria
Poizat, Ghislaine
Keryer, Guy
Humbert, Sandrine
Saudou, Frédéric
author_sort Pardo, Raúl
collection PubMed
description BACKGROUND: Huntingtin (htt) is a multi-domain protein of 350 kDa that is mutated in Huntington's disease (HD) but whose function is yet to be fully understood. This absence of information is due in part to the difficulty of manipulating large DNA fragments by using conventional molecular cloning techniques. Consequently, few studies have addressed the cellular function(s) of full-length htt and its dysfunction(s) associated with the disease. RESULTS: We describe a flexible synthetic vector encoding full-length htt called pARIS-htt (Adaptable, RNAi Insensitive &Synthetic). It includes synthetic cDNA coding for full-length human htt modified so that: 1) it is improved for codon usage, 2) it is insensitive to four different siRNAs allowing gene replacement studies, 3) it contains unique restriction sites (URSs) dispersed throughout the entire sequence without modifying the translated amino acid sequence, 4) it contains multiple cloning sites at the N and C-ter ends and 5) it is Gateway compatible. These modifications facilitate mutagenesis, tagging and cloning into diverse expression plasmids. Htt regulates dynein/dynactin-dependent trafficking of vesicles, such as brain-derived neurotrophic factor (BDNF)-containing vesicles, and of organelles, including reforming and maintenance of the Golgi near the cell centre. We used tests of these trafficking functions to validate various pARIS-htt constructs. We demonstrated, after silencing of endogenous htt, that full-length htt expressed from pARIS-htt rescues Golgi apparatus reformation following reversible microtubule disruption. A mutant form of htt that contains a 100Q expansion and a htt form devoid of either HAP1 or dynein interaction domains are both unable to rescue loss of endogenous htt. These mutants have also an impaired capacity to promote BDNF vesicular trafficking in neuronal cells. CONCLUSION: We report the validation of a synthetic gene encoding full-length htt protein that will facilitate analyses of its structure/function. This may help provide relevant information about the cellular dysfunctions operating during the disease. As proof of principle, we show that either polyQ expansion or deletion of key interacting domains within full-length htt protein impairs its function in transport indicating that HD mutation induces defects on intrinsic properties of the protein and further demonstrating the importance of studying htt in its full-length context.
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spelling pubmed-28878452010-06-19 pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking Pardo, Raúl Molina-Calavita, Maria Poizat, Ghislaine Keryer, Guy Humbert, Sandrine Saudou, Frédéric Mol Brain Research BACKGROUND: Huntingtin (htt) is a multi-domain protein of 350 kDa that is mutated in Huntington's disease (HD) but whose function is yet to be fully understood. This absence of information is due in part to the difficulty of manipulating large DNA fragments by using conventional molecular cloning techniques. Consequently, few studies have addressed the cellular function(s) of full-length htt and its dysfunction(s) associated with the disease. RESULTS: We describe a flexible synthetic vector encoding full-length htt called pARIS-htt (Adaptable, RNAi Insensitive &Synthetic). It includes synthetic cDNA coding for full-length human htt modified so that: 1) it is improved for codon usage, 2) it is insensitive to four different siRNAs allowing gene replacement studies, 3) it contains unique restriction sites (URSs) dispersed throughout the entire sequence without modifying the translated amino acid sequence, 4) it contains multiple cloning sites at the N and C-ter ends and 5) it is Gateway compatible. These modifications facilitate mutagenesis, tagging and cloning into diverse expression plasmids. Htt regulates dynein/dynactin-dependent trafficking of vesicles, such as brain-derived neurotrophic factor (BDNF)-containing vesicles, and of organelles, including reforming and maintenance of the Golgi near the cell centre. We used tests of these trafficking functions to validate various pARIS-htt constructs. We demonstrated, after silencing of endogenous htt, that full-length htt expressed from pARIS-htt rescues Golgi apparatus reformation following reversible microtubule disruption. A mutant form of htt that contains a 100Q expansion and a htt form devoid of either HAP1 or dynein interaction domains are both unable to rescue loss of endogenous htt. These mutants have also an impaired capacity to promote BDNF vesicular trafficking in neuronal cells. CONCLUSION: We report the validation of a synthetic gene encoding full-length htt protein that will facilitate analyses of its structure/function. This may help provide relevant information about the cellular dysfunctions operating during the disease. As proof of principle, we show that either polyQ expansion or deletion of key interacting domains within full-length htt protein impairs its function in transport indicating that HD mutation induces defects on intrinsic properties of the protein and further demonstrating the importance of studying htt in its full-length context. BioMed Central 2010-06-01 /pmc/articles/PMC2887845/ /pubmed/20515468 http://dx.doi.org/10.1186/1756-6606-3-17 Text en Copyright ©2010 Pardo et al; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research
Pardo, Raúl
Molina-Calavita, Maria
Poizat, Ghislaine
Keryer, Guy
Humbert, Sandrine
Saudou, Frédéric
pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking
title pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking
title_full pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking
title_fullStr pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking
title_full_unstemmed pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking
title_short pARIS-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking
title_sort paris-htt: an optimised expression platform to study huntingtin reveals functional domains required for vesicular trafficking
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2887845/
https://www.ncbi.nlm.nih.gov/pubmed/20515468
http://dx.doi.org/10.1186/1756-6606-3-17
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