Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Antisense oligonucleotide-mediated disruption of HTT caspase-6 cleavage site ameliorates the phenotype of YAC128 Huntington disease mice

ABSTRACT: In Huntington’s Disease, cellular toxicity is particularly caused by toxic protein fragments generated from the mutant huntingtin (HTT) protein. By modifying the HTT protein, we aim to reduce proteolytic cleavage and ameliorate the consequences of mutant HTT without lowering total HTT levels. To that end, we use an antisense oligonucleotide (AON) that targets HTT pre-mRNA and induces partial skipping of exon 12, which contains the critical caspase-6 cleavage site. Here, we show that AON-treatment can partially restore the phenotype of YAC128 mice, a mouse model expressing the full-length human HTT gene including 128 CAG-repeats. Wild-type and YAC128 mice were treated intracerebroventricularly with AON12.1, scrambled AON or vehicle starting at 6 months of age and followed up to 12 months of age, when MRI was performed and mice were sacrificed. AON12.1 treatment induced around 40% exon skip and protein modification. The phenotype on body weight and activity, but not rotarod, was restored by AON treatment. Genes differentially expressed in YAC128 striatum changed towards wild-type levels and striatal volume was preserved upon AON12.1 treatment. However, scrambled AON also showed a restorative effect on gene expression and appeared to generally increase brain volume.

ORGANISM(S): Mus musculus

PROVIDER: GSE239312 | GEO | 2023/12/01

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Expression analysis of PC3 cells treated with scramble AON or AON directed against MBNL1

Project description:We transfected PC3 cells with 100nM of a scrambled antisense oligonucleotide (AON) and an AON directed against MBNL1 exon 7 (36 basepairs) in order to skip the latter. Cells were harvested at 72h post-transfection and RNAseq was performed with ribozero depletion.

2018-09-06 | GSE114383 | GEO

In vivo CRISPR base editing for treatment of Huntington’s disease

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

Discovery of novel isoforms of Huntingtin reveals a new hominid-specific exon

Project description:Huntington’s disease (HD) is a devastating neurological disorder that is caused by an expansion of the poly-Q tract in exon 1 of the Huntingtin gene (HTT). HTT is an evolutionarily conserved and ubiquitously expressed protein that has been linked to a variety of functions including transcriptional regulation, mitochondrial function, and vesicle transport. This large protein has numerous caspase and calpain cleavage sites and can be decorated with several post-translational modifications such as phosphorylations, acetylations, sumoylations, and palmitoylations. However, the exact function of HTT and the role played by its modifications in the cell is still not well understood. Scrutiny of HTT function has been focused on a single, full length, mRNA. In this study, we report the discovery of 5 novel HTT mRNA splice isoforms that are expressed in normal and HD-hESC lines as well as cortical neurons differentiated from hESCs. Interestingly, none of the novel isoforms generates a truncated protein. Instead, 4 of the 5 new isoforms specifically eliminate domains and modifications to generate smaller HTT proteins. The fifth novel isoform incorporates a previously unreported additional exon, dubbed 41b, which is hominid-specific and introduces a potential phosphorylation site in the protein. The discovery of this hominid-specific isoform may shed light on human-specific pathogenic mechanisms of HTT, which could not be investigated with current mouse models of the disease. Furthermore, it provides a new human-specific target for drug screening in Huntington’s disease. We performed RNAseq of human embryonic stem cells in pluripotency conditions to check expression of multiple HTT isoforms.

2015-06-10 | E-GEOD-66769 | biostudies-arrayexpress

RNA-Targeting CRISPR/Cas13d System Alleviates Disease-Related Phenotypes in Pre-clinical Models of Huntington’s Disease (Human).

Project description:Huntington's disease (HD) is a fatal, dominantly inherited neurodegenerative disorder caused by a CAG trinucleotide expansion in exon 1 of the huntingtin (HTT) gene. Although the pathogenesis of HD remains complex, the CAG-expanded (CAGEX) HTT mRNA and protein ultimately causes disease through a toxic gain-of-function mechanism. As the reduction of pathogenic mutant HTT mRNA is beneficial as a treatment, we developed a mutant allele-sensitive CAGEX RNA-targeting CRISPR-Cas13d system (Cas13d/CAGEX) that eliminates toxic CAGEX RNA in HD patient-derived fibroblasts and iPSC-derived striatal neurons. We show that intrastriatal delivery of Cas13d/CAGEX via a single adeno-associated viral vector, serotype 9 (AAV9) mediates significant and selective reduction of mutant HTT mRNA and protein levels within the striatum of heterozygous zQ175 mice, an established mouse model of HD. Moreover, the reduction of mutant HTT mRNA renders a sustained partial reversal of HD phenotypes, including improved motor coordination, attenuated striatal atrophy, and reduction of mutant HTT protein aggregates. Importantly, phenotypic improvements were durable for at least 8 months without gross or behavioral adverse effects, and with minimal off-target interactions of Cas13d/CAGEX in the mouse transcriptome. Taken together, we demonstrate a proof-of-principle of an RNA-targeting CRISPR/Cas13d system as a therapeutic approach for HD, a strategy with broad implications for the treatment of other dominantly inherited neurodegenerative disorders.

2022-11-15 | GSE214108 | GEO

RNA-Targeting CRISPR/Cas13d System Alleviates Disease-Related Phenotypes in Pre-clinical Models of Huntington’s Disease (Mouse).

2022-11-15 | GSE214109 | GEO

Discovery of novel isoforms of Huntingtin reveals a new hominid-specific exon

2015-06-10 | GSE66769 | GEO

Contribution of Nuclear and Extranuclear PolyQ to Neurological Phenotypes in Mouse Models of Huntington’s Disease

Project description:To dissect the impact of nuclear and extranuclear mutant htt on the initiation and progression of disease, we generated a series of transgenic mouse lines in which nuclear localization (NLS) or nuclear export sequences (NES) have been placed N-terminal to the htt exon 1 protein carrying 144 glutamines. Our data indicate that the exon 1 mutant protein is present in the nucleus as part of an oligomeric or aggregation complex. Increasing the concentration of the mutant transprotein in the nucleus is sufficient for, and dramatically accelerates the onset and progression of behavioral phenotypes. Furthermore, nuclear exon 1 mutant protein is sufficient to induce cytoplasmic neurodegeneration and transcriptional dysregulation. However, our data suggests that cytoplasmic mutant exon 1 htt, if present, contributes to disease progression. Keywords: Trangenic mouse brain gene expression

2005-09-07 | GSE3248 | GEO

Proteolysis resistant huntingtin isoform induced by antisense oligonucleotide maintains normal huntingtin function in mouse

Project description:Huntington’s disease (HD) is a late onset neurological disorder for which no neuroprotective therapies efficiently delay onset or progression. A key pathological mechanism in disease involves the proteolysis of polyglutamine (polyQ)-expanded mutant huntingtin (mHTT) generating polyQ-containing N-terminal fragments that are crucial contributors to HD pathogenesis since inhibition of the cleavage at the putative caspase-6 site reduces pathology in a HD mouse model. Interestingly, a naturally occurring alternative spliced form of HTT lacking exon12 (HTTΔ12) leads to a protein with an internal deletion of the caspase-6 N-terminal cleavage site. Here, we have taken a multidisciplinary approach to characterize the therapeutic potential of targeting exon12 of HTT. We show that HTTΔ12 is fully resistant to caspase-6 cleavage in both cell-free and tissue lysate assays, while maintaining overall biochemical and structural properties similar to wild-type (wt)-HTT. We generated mouse deleted for exon12 and found that exon12 is dispensable for HTT main physiological functions including embryonic development and intracellular trafficking such as BDNF transport. Finally, we pharmacologically induced HTTΔ12 using an antisense oligonucleotide (ASO). QRX-704 ASO efficiently distributes in the whole brain, is stable several months, and reduces pathogenic proteolysis. Thus, ASO-induced exon12 deletion of HT We performed gene expression profiling analysis using data obtained from RNA-seq of brain tissue (cortex and striatum) samples originating from mouse littermates from HttΔ12 (Δ12;KI) and HttKO (KO) lines at 3 month of age.

2022-07-29 | GSE209893 | GEO

HAP40 orchestrates huntingtin structure for differential interaction with polyglutamine expanded exon 1

Project description:Huntington’s disease results from expansion of a glutamine-coding CAG tract in the huntingtin (HTT) gene, producing an aberrantly functioning form of HTT. Both wildtype and disease-state HTT form a hetero-dimer with HAP40 of unknown functional relevance. We demonstrate in vivo and in cell models that HTT and HAP40 cellular abundance are coupled. Integrating data from a 2.6 Å cryo-electron microscopy structure, cross-linking mass spectrometry, small-angle X-ray scattering, and modeling, we provide a near-atomic-level view of HTT, its molecular interaction surfaces and compacted domain architecture, orchestrated by HAP40. Native mass-spectrometry reveals a remarkably stable hetero-dimer, potentially explaining the cellular inter-dependence of HTT and HAP40. The exon 1 region of HTT is dynamic but shows greater conformational variety in the polyglutamine expanded mutant than wildtype exon 1. Our data provide a foundation for future functional and drug discovery studies targeting Huntington’s disease and illuminate the structural consequences of HTT polyglutamine expansion.

2022-02-21 | PXD028313 | Pride

HAP40 orchestrates huntingtin structure for differential interaction with polyglutamine expanded exon 1

2022-09-09 | PXD028415 | Pride