Expression analysis in yeast model of Huntington's disease (HD)
Ontology highlight
ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae
PROVIDER: GSE18644 | GEO | 2010/11/09
SECONDARY ACCESSION(S): PRJNA121577
REPOSITORIES: GEO
Similar Datasets
Project description:Expressing a mutant fragment of huntingtin (Htt) in yeast produces several HD-relevant phenotypes. We used microarrays to study global change in expression induced by this mutant htt fragment. Expression was also analysed in three suppressor deletion strains expressing a toxic mutant htt fragment: bna4Δ, mbf1Δ, and ume1Δ. Yeast samples expressing either a wild-type or mutant htt fragment (Htt25Q or Htt103Q, respectively), and suppressor deletion strains expressing Htt103Q: bna4Δ, mbf1Δ, and ume1Δ.
2010-11-09 | E-GEOD-18644 | biostudies-arrayexpress
Project description:Huntington's disease (HD) is a dominantly inherited genetic disease caused by mutant huntingtin (htt) protein with expanded polyglutamine tracts. A neuropathological hallmark of HD is the presence of neuronal inclusions of mutant htt. p62 is an important regulatory protein in selective autophagy, a process by which aggregated proteins are degraded, and it is associated with several neurodegenerative disorders including HD. Here we investigated the effect of p62 depletion in three HD model mice: R6/2, HD190QG and HD120QG mice. We found that loss of p62 in these models led to longer lifespans and reduced nuclear inclusions, although cytoplasmic inclusions increased with polyglutamine length. In mouse embryonic fibroblasts (MEFs) with or without p62, mutant htt with a nuclear localization signal (NLS) showed no difference in nuclear inclusion between the two MEF types. In the case of mutant htt without NLS, however, p62 depletion increased cytoplasmic inclusions. Furthermore, to examine the effect of impaired autophagy in HD model mice, we crossed R6/2 mice with Atg5 conditional knockout mice. These mice also showed decreased nuclear inclusions and increased cytoplasmic inclusions, similar to HD mice lacking p62. These data suggest that the genetic ablation of p62 in HD model mice enhances cytoplasmic inclusion formation by interrupting autophagic clearance of polyQ inclusions. This reduces polyQ nuclear influx and paradoxically ameliorates disease phenotypes by decreasing toxic nuclear inclusions. Gene expression profiles were analyzed to examine the effects of p62 depletion in mouse with or without mutant huntingtin exon 1 To examine the effect of p62 depletion on the transcriptome of Huntington's disease model mice, we crossed p62 knockout mice with HD model mice. We extracted total RNA from the striatum of these mice at 8 weeks and used for a microaaray analysis. The samples are HD transgenic mice with p62 knockout (HD_p62KO), HD mice with normal p62 (HD_p62WT), non-HD-transgenic mice with p62 knockout (NT_p62KO), and non-HD-transgenic mice with normal p62 (NT_p62WT).
2014-10-10 | E-GEOD-62210 | biostudies-arrayexpress
Project description:Huntington's disease (HD) is a neurodegenerative polyglutamine (polyQ) disease resulting from the expansion of CAG repeats located in the ORF of the huntingtin gene (HTT). The extent to which mutant mRNA‐driven disruptions contribute to HD pathogenesis, particularly in comparison to the dominant mechanisms related to the gain‐of‐function effects of the mutant polyQ protein, is still debatable. To evaluate this contribution in vivo, we generated two mouse models through a knock‐in strategy at the Rosa26 locus. These models expressed distinct variants of human mutant HTT cDNA fragment: a translated variant (HD/100Q model, serving as a reference) and a nontranslated variant (HD/100CAG model). The cohorts of animals were subjected to a broad spectrum of molecular, behavioral, and cognitive analysis for 21 months. Behavioral testing revealed alterations in both models, with the HD/100Q model exhibiting late disease phenotype. The rotarod, static rod, and open‐field tests showed some motor deficits in HD/100CAG and HD/100Q model mice during the light phase, while ActiMot indicated hyperkinesis during the dark phase. Both models also exhibited certain gene deregulations in the striatum that are related to disrupted pathways and phenotype alterations observed in HD. In conclusion, we provide in vivo evidence for a minor contributory role of mutant RNA in HD pathogenesis. The separated effects resulting from the presence of mutant RNA in the HD/100CAG model led to less severe but, to some extent, similar types of impairments as in the HD/100Q model. Increased anxiety was one of the most substantial effects caused by mutant HTT RNA.
2024-06-23 | GSE269068 | GEO
Project description:Huntington's disease (HD) is an inherited and ultimately fatal neurodegenerative disorder caused by an expanded polyglutamine-encoding CAG repeat within exon 1 of the huntingtin (HTT) gene, which produces a mutant protein that destroys striatal and cortical neurons.Importantly, a critical event in the pathogenesis of HD is the proteolytic cleavage of the mutant HTT protein by caspase-6, which generates fragments of the N-terminal domain of the protein that form highly toxic aggregates. Given the role that proteolysis of the mutant HTT protein plays in HD, strategies forpreventing this process hold potential for treating the disorder.By screening 141 CRISPR base editor variants targeting splice elements in the HTT gene, we identified platforms capable of producing HTT protein isoforms resistant to caspase-6-mediated proteolysis via editing of the splice acceptor sequence for exon 13. When delivered to the striatum of a rodent HD model, these base editors induced efficient exon skipping and decreased the formation of the N-terminal fragments, which in turn reduced HTT protein aggregation and attenuatedstriatal and cortical atrophy.Collectively, these results illustrate the potential for CRISPR base editing to decrease the toxicity of the mutant HTT protein for HD.
2024-07-12 | GSE272134 | GEO
Project description:We used microarrays to investigate whether transcriptional dysregulation in hypothalamus is caused by expression of the huntingtin (HTT) protein We used two different Huntington's disease mouse models: BACHD mice with ubiquitous full-length mutant HTT expression (97 CAG repeats) and wild-type mice with targeted bilateral injections of wild-type or mutant HTT (853 amino acids length, wild-type HTT: 18 CAG repeats, mutant HTT: 79 CAG repeats) in hypothalamus.
2022-10-18 | GSE215217 | GEO
Project description:Huntington's disease (HD) is a devastating neurodegenerative disorder caused by the expansion of CAG repeats in the huntingtin (HTT) gene. Recent advances in gene editing technologies, such as CRISPR/CasRx, have opened new avenues for therapeutic interventions. In this study, we explored the efficacy of CRISPR/CasRx, which can specifically and accurately digest single-stranded RNA and down-regulate the expression of related genes, in targeting the HTT mRNA and its potential as a treatment strategy for HD. Our results showed that CRISPR/CasRx could significantly down-regulate HTT mRNA in different models, including human embryonic kidney (HEK) 293T cells, HD140Q-knockin (HD 140Q-KI) mice at various disease stages, and Huntingtin knockin (HD-KI) pigs, and lead to a subsequent decrease in the expression of mutant Huntingtin (mHTT) protein. Moreover, this intervention could significantly ameliorate the neurological symptoms in HD 140Q-KI mice and HD-KI pigs. These findings highlight the effectiveness of the RNA-targeting CRISPR/CasRx as a potential therapeutic strategy for HD. Furthermore, the success of this approach provides valuable insights and novel avenues for the treatment of other genetic disorders caused by gene mutations.
2024-12-01 | GSE248873 | GEO
Project description:We report that the SUMO-targeted ubiquitin ligase (STUbL) Slx5 reduces the toxicity and abnormal transcriptional activity of a mutant, aggregation-prone fragment of huntingtin (htt), the causative agent of HD. An extra copy of SLX5 specifically reduces htt aggregates in the cytosol as well as chromatin-associated htt aggregates in the nucleus. Using RNA sequencing, we identified and confirmed specific targets of mHtt's transcriptional activity that are modulated by Slx5.
2018-06-20 | GSE115990 | GEO
Project description:Huntington’s disease (HD) is a hereditary neurodegenerative disorder caused by abnormal expansion of cytosine-adenine-guanine (CAG) trinucleotide repeats in the huntingtin gene (HTT). The resultant mutant protein is ubiquitously expressed and drives pathogenesis of HD through a toxic gain-of-function mechanism. Animal models of HD have demonstrated that reducing huntingtin protein (HTT) levels alleviates HD-associated motor and neuropathological abnormalities, confirming the importance of huntingtin-lowering as a therapeutic approach. Several therapies in development repress HTT transcription or translation, including antisense oligonucleotides, virally-delivered microRNAs, and zinc finger protein transcription factors. However, they all require invasive procedures to reach the central nervous system (CNS) and do not distribute evenly to target areas in the brain. Systemically distributed therapeutics are needed to address the CNS and peripheral dysfunctions associated with HD. Here we report the discovery of small molecule splicing modifiers that lower HTT expression by selective modulation of pre-mRNA splicing. These compounds promote the inclusion of a pseudoexon containing a premature termination codon triggering HTT mRNA degradation and a reduction of HTT protein levels in vitro and in vivo. These orally bioavailable small molecules represent a non-invasive treatment option for HD and our findings support their continued development for the treatment of HD.
2021-07-01 | GSE162813 | GEO
Project description:Huntington’s disease (HD) is a hereditary neurodegenerative disorder caused by abnormal expansion of cytosine-adenine-guanine (CAG) trinucleotide repeats in the huntingtin gene (HTT). The resultant mutant protein is ubiquitously expressed and drives pathogenesis of HD through a toxic gain-of-function mechanism. Animal models of HD have demonstrated that reducing huntingtin protein (HTT) levels alleviates HD-associated motor and neuropathological abnormalities, confirming the importance of huntingtin-lowering as a therapeutic approach. Several therapies in development repress HTT transcription or translation, including antisense oligonucleotides, virally-delivered microRNAs, and zinc finger protein transcription factors. However, they all require invasive procedures to reach the central nervous system (CNS) and do not distribute evenly to target areas in the brain. Systemically distributed therapeutics are needed to address the CNS and peripheral dysfunctions associated with HD. Here we report the discovery of small molecule splicing modifiers that lower HTT expression by selective modulation of pre-mRNA splicing. These compounds promote the inclusion of a pseudoexon containing a premature termination codon triggering HTT mRNA degradation and a reduction of HTT protein levels in vitro and in vivo. These orally bioavailable small molecules represent a non-invasive treatment option for HD and our findings support their continued development for the treatment of HD.
2021-07-01 | GSE162812 | GEO
Project description:Huntington’s disease (HD) is a dominantly inherited neurodegenerative disorder caused by a CAG trinucleotide expansion in the huntingtin gene (HTT), which codes for the pathologic mutant HTT (mHTT) protein. Since normal HTT is thought to be important for brain function, we engineered zinc finger protein transcription factors (ZFP-TFs) to target the pathogenic CAG repeat and selectively lower mHTT as a therapeutic strategy. Using patient-derived fibroblasts and neurons, we demonstrate that ZFP-TFs selectively repress >99% of HD-causing alleles over a wide dose range, while preserving expression of >86% of normal alleles. Other CAG-containing genes are minimally affected, and virally delivered ZFP-TFs are active and well tolerated in HD neurons beyond 100 days in culture and at least 9 months in the mouse brain. Using three HD mouse models, we demonstrate improvements in a range of molecular, histopathological, electrophysiological, and functional endpoints. Our findings support the continued development of an allele-selective ZFP-TF for the treatment of HD.
2019-06-30 | GSE127820 | GEO