Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

TDP1 mutation causing SCAN1 neurodegenerative syndrome hampers the repair of transcriptional DNA double-strand breaks

ABSTRACT: TDP1 removes transcription-blocking TOP1 cleavage complexes (TOP1ccs) and its inactivating H493R mutation causes the neurodegenerative syndrome SCAN1. However, the molecular mechanism underlying SCAN1 phenotype is unclear. Here, we generate human SCAN1 cell models using CRISPR/Cas9 and show that they accumulate TOP1ccs along with changes in gene expression and genomic distribution of R-loops. SCAN1 cells also accumulate transcriptional DNA double-strand breaks (DSBs) specifically in the G1 cell population due to increased DSB formation and lack of repair, both resulting from abortive removal of transcription-blocking TOP1ccs. Deficient TDP1 activity causes increased DSB production and the presence of mutated TDP1 protein hampers DSB repair by a TDP2-dependent back-up pathway. This study provides powerful models to study TDP1 functions under physiological and pathological conditions and unravels that a gain of function of the mutated TDP1 protein, which prevents DSB repair, rather than a loss of TDP1 activity itself, could contribute to SCAN1 pathogenesis.

ORGANISM(S): Homo sapiens

PROVIDER: GSE226263 | GEO | 2024/04/25

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Transcriptional effects of TDP1 deficiency in non-replicating U2OS cells

Project description:Spinocerebellar ataxia with axonal neuropathy (SCAN1) is a rare recessive neurodegenerative syndrome associated with cerebellar atrophy and peripheral neuropathy. It is caused by a homozygous missense mutation in the tyrosyl-DNA phosphodiesterase-1 (TDP1) gene (A1478G). resulting in a substitution of histidine for arginine-493 (H493R) in the TDP1 catalytic site, leading to reduced TDP1 activity. How TDP1 H493R mutation promotes the SCAN1 phenotype, which is associated with the death of post-mitotic neurons, is unclear. We have generated models of osteosarcoma U2OS cells homozygous for TDP1 H493R employing the CRISPR-Cas9 technique (2 clones, named “1P” and “3.3”). Here, we have generated transcriptional genome wide profile in order to characterize differences in gene expression that are specific of TDP1-mutated clones.

2024-04-30 | GSE186693 | GEO

Investigation of genetic compensation in tdp1-/- zebrafish embryos

Project description:Tdp1, tyrosyl-DNA phosphodiesterase 1, is an enzyme responsible for the repair of DNA breaks resulting from aberrant topoisomerase 1 activity, called Top1 cleavage complexes (Top1-CCs). Mutation of Tdp1 leads to a progressive neurodegenerative disorder spinocerebellar ataxia with axonal neuropathy 1 (SCAN1). We have generated tdp1-/- zebrafish as a model for SCAN1. The adult fish have a behavioral defect and hypersensitivity to camptothecin (CPT), a Top1 poison. Strikingly, the embryos do not show increased sensitivity to CPT, unlike any other reported vertebrate models, suggesting genetic compensation is at play at this stage. We thus carried out microarray analysis in CPT-treated zebrafish embryos to compare the gene expression profiles of tdp1WT and tdp1-/- genotypes. Gene expression analysis revealed 1,8111 genes that were differentially expressed: 1,071 were upregulated and 740 were downregulated. Sprtn and neil1, two potential compensation candidates were upregulated in the tdp1-/- embryos.

2022-04-19 | GSE148923 | GEO

TDP1 gene knockout effect on transcriptome

Project description:TDP1 is an enzyme that in humans is encoded by the TDP1 gene.[5][6][7] TDP1 is the protein involved in repairing stalled topoisomerase I-DNA complexes. We evaluated the effect of Tdp1 knockout in HEK293A cells on the gene expression.

2023-11-20 | GSE247361 | GEO

TDP1 phosphorylation at S61 promotes Top1cc repair via the MUS81-dependent pathway during mitosis

Project description:Topoisomerase 1 (Top1) removes supercoils from DNA during replication and transcription, is critical for mitotic progression to the G1 phase, and ensures DNA topology. Tyrosyl-DNA phosphodiesterase 1 (TDP1) mediates the removal of trapped Top1-DNA covalent complexes (Top1ccs). Here, we identify CDK1-dependent phosphorylation of TDP1 at S61 residue during mitosis. TDP1 defective for S61 phosphorylation (TDP1S61A) is trapped on the mitotic chromosomes, triggering DNA damage and mitotic defects. Moreover, we show that Top1cc repair in mitosis occurs via MUS81-dependent mitotic DNA repair mechanism. Replication stress (RS) induced by Camptothecin (CPT) or Aphidicolin (APH) leads to TDP1S61A enrichment at common fragile sites (CFSs), which over-stimulates MUS81-dependent chromatid breaks, anaphase bridges, and micronuclei, ultimately culminating in 53BP1 nuclear bodies in the G1-phase. Our findings provide a new insight into the cell cycle-dependent regulation of TDP1 dynamics forthe repair of trapped Top1ccs during mitosis that prevents genomic instability following RS.

2024-06-26 | PXD053309 | Pride

TDP1 mutation causing SCAN1 neurodegenerative syndrome hampers the repair of transcriptional DNA double-strand breaks

Project description:TDP1 mutation causing SCAN1 neurodegenerative syndrome hampers the repair of transcriptional DNA double-strand breaks

| PRJNA939255 | ENA

Ma2005-digital response of p53 to DNA damage-ATM Activation Module

Project description:Recent observations show that the single-cell response of p53 to ionizing radiation (IR) is “digital” in that it is the number of oscillations rather than the amplitude of p53 that shows dependence on the radiation dose. We present a model of this phenomenon. In our model, double-strand break (DSB) sites induced by IR interact with a limiting pool of DNA repair proteins, forming DSB–protein complexes at DNA damage foci. The persisting complexes are sensed by ataxia telangiectasia mutated (ATM), a protein kinase that activates p53 once it is phosphorylated by DNA damage. The ATM-sensing module switches on or off the downstream p53 oscillator, consisting of a feedback loop formed by p53 and its negative regulator, Mdm2. In agreement with experiments, our simulations show that by assuming stochasticity in the initial number of DSBs and the DNA repair process, p53 and Mdm2 exhibit a coordinated oscillatory dynamics upon IR stimulation in single cells, with a stochastic number of oscillations whose mean increases with IR dose. The damped oscillations previously observed in cell populations can be explained as the aggregate behavior of single cell

2020-05-13 | MODEL2005130001 | BioModels

TDP1 gene knockout effect on transcriptome

Project description:TDP1 gene knockout effect on transcriptome

| PRJNA1037162 | ENA

A Role for Small RNAs in DNA Double-Strand Break Repair

Project description:Here we identify a novel class of small RNAs that are ~21-nucleotide in length and are produced from the sequences in the vicinity of DNA double strand break (DSB) sites in Arabidopsis and humans. We named them diRNAs for DSB-induced small RNAs. In Arabidopsis, the biogenesis of diRNAs requires the PI3 kinase ATR, RNA polymerase IV (Pol IV), and Dicer-like proteins. Mutations in these proteins as well as in Pol V cause significant reduction in DSB repair efficiency. diRNAs are recruited by Argonaute 2 (AGO2) to mediate DSB repair. In humans, knocking down Dicer or Ago2 causes a significant reduction in DSB repair. Our findings reveal a novel biological function for small RNAs in the DSB repair pathway. We propose that diRNAs may function as guide molecules for chromatin modifications or recruitment of repair complexes at DSB sites to facilitate repair. 28 samples from Arabidopsis thaliana in various genetic backgrounds and 5 samples from the human cells, small RNA sequencing

2012-03-26 | E-GEOD-36338 | biostudies-arrayexpress

RAD54L2 mediates a novel mechanism to counter TOP2-DNA adducts

Project description:The catalytic cycle of topoisomerase 2 (TOP2) enzymes proceeds via a transient DNA double-strand break (DSB) intermediate termed the TOP2 cleavage complex (TOP2cc), in which the TOP2 protein is covalently bound to DNA. Anti-cancer agents such as etoposide operate by stabilising TOP2ccs, ultimately generating genotoxic TOP2-DNA protein crosslinks that require processing and repair. Here, we identify RAD54L2 as a factor promoting TOP2cc resolution. We demonstrate that RAD54L2 acts through a novel mechanism together with ZNF451 and independent of TDP2. Our work suggests a model wherein RAD54L2 recognises sumoylated-TOP2 and, using its ATPase activity, promotes TOP2cc resolution and prevents DSB exposure. These findings suggest RAD54L2-mediated TOP2cc resolution as a potential mechanism for cancer-therapy resistance and highlight RAD54L2 as an attractive candidate for drug discovery.

2024-01-26 | PXD046611 | Pride

A Role for Small RNAs in DNA Double-Strand Break Repair

2012-03-27 | GSE36338 | GEO