Telomere dysfunction
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE4627 | GEO | 2006/07/01
SECONDARY ACCESSION(S): PRJNA95523
REPOSITORIES: GEO
Similar Datasets
Project description:We used microarrays to analyze the prevalence of signalling induced by acute telomere dysfunction (as induced by TRF2DBDM expression = Dataset 1) and in TERC- compared to TERC+ HCC (Dataset 2). Experiment Overall Design: Presented are gene expression data from: Experiment Overall Design: Dataset 1: Mouse liver 48h after i.v. infection of p53-/- mice with Ad TRF2DBDM compared to Ad GFP (2x10^10 PFU) (GSM103546, GSM103547) and Experiment Overall Design: Dataset 2: p53-/- heptaocellular carcinoma (HCC) from mTERC+ HBs (GSM103548, GSM103549, GSM103553) compared to mTERC-, HBs (GSM103550, GSM103551, GSM103552) transgenic mice. Experiment Overall Design: All mice were in a C57BL/6J background. Experiment Overall Design: Dataset 1: Liver RNA was extracted 48h after adenoviral infection (n=3 mice/group), samples were pooled for hybridization on Affymetrix microarrays. Experiment Overall Design: Dataset 2: RNA was extracted from HCC of 12-15month old mTERC+ and mTERC- mice (n=3 mice/group). Individual tumors were hybridized on Affymetrix microarrays. Experiment Overall Design: Differentially expressed gene clusters were identified using Array Assist 4.0 (Stratagene).
2008-06-13 | E-GEOD-4627 | biostudies-arrayexpress
Project description:Somatic cell nuclear transfer (SCNT) and induced pluripotent stem cells (iPSCs) represent two major approaches for somatic cell reprogramming. However, little attention has been paid to the ability of these two strategies in rejuvenating cells from donors with aging associated syndrome. Here, we utilized telomerase deficient (Terc-/-) mice to probe this question. SCNT-derived embryonic stem cells (ntESCs) and iPSCs were successfully derived from second generation (G2) and third generation (G3) of Terc-/- mice, and ntESCs showed better differentiation potential and self-renewal ability. Telomeres lengthened extensively in cloned embryos while remained or slightly increased in the process of iPSCs induction. Furthermore, G3 ntESCs exhibited improvement of telomere capping function as evidenced by decreased signal free ends and chromosome end-to-end fusion events. In contrast, there was a further decline of telomere capping function in G3 iPSCs. In addition to telomere dysfunction, mitochondria function was severely impaired in G3 iPSCs as evidenced by oxygen consumption rate (OCR) decline, reactive oxygen species (ROS) accumulation and dramatically increased mitochondria genome mutations while these deficiencies were greatly mitigated in G3 ntESCs. Our data proved the principle that SCNT-mediated reprogramming appears more superior than transcription factors induced reprogramming in terms of the resetting of telomere quality and mitochondria function, and thus, providing valuable information for further improvement of transcription factors mediated reprogramming. We compared the gene expression profile of G3 Terc-/- ntES and G3 Terc-/- iPS. Three biological repeats were included for each cell line.
2013-11-11 | E-GEOD-46860 | biostudies-arrayexpress
Project description:The telomerase RNA component (TERC) is a critical determinant of cellular self renewal. Poly(A)-specific ribonuclease (PARN) is required for post-transcriptional maturation of TERC. PARN mutations lead to incomplete 3â² end processing and increased destruction of nascent TERC RNA transcripts, resulting in telomerase deficiency and telomere diseases. Here, we determined that overexpression of TERC increased telomere length in PARN-deficient cells and hypothesized that decreasing post-transcriptional 3â² oligo-adenylation of TERC would counteract the deleterious effects of PARN mutations. Inhibition of the noncanonical poly(A) polymerase PAP-associated domainâcontaining 5 (PAPD5) increased TERC levels in PARN-mutant patient cells. PAPD5 inhibition was also associated with increases in TERC stability, telomerase activity, and telomere elongation. Our results demonstrate that manipulating post-transcriptional regulatory pathways may be a potential strategy to reverse the molecular hallmarks of telomere disease. mRNA sequencing of induced pluripotent stem cells and 293 cell line.
2016-08-02 | E-GEOD-81507 | biostudies-arrayexpress
Project description:Somatic cell nuclear transfer (SCNT) and induced pluripotent stem cells (iPSCs) represent two major approaches for somatic cell reprogramming. However, little attention has been paid to the ability of these two strategies in rejuvenating cells from donors with aging associated syndrome. Here, we utilized telomerase deficient (Terc-/-) mice to probe this question. SCNT-derived embryonic stem cells (ntESCs) and iPSCs were successfully derived from second generation (G2) and third generation (G3) of Terc-/- mice, and ntESCs showed better differentiation potential and self-renewal ability. Telomeres lengthened extensively in cloned embryos while remained or slightly increased in the process of iPSCs induction. Furthermore, G3 ntESCs exhibited improvement of telomere capping function as evidenced by decreased signal free ends and chromosome end-to-end fusion events. In contrast, there was a further decline of telomere capping function in G3 iPSCs. In addition to telomere dysfunction, mitochondria function was severely impaired in G3 iPSCs as evidenced by oxygen consumption rate (OCR) decline, reactive oxygen species (ROS) accumulation and dramatically increased mitochondria genome mutations while these deficiencies were greatly mitigated in G3 ntESCs. Our data proved the principle that SCNT-mediated reprogramming appears more superior than transcription factors induced reprogramming in terms of the resetting of telomere quality and mitochondria function, and thus, providing valuable information for further improvement of transcription factors mediated reprogramming.
2013-11-11 | GSE46860 | GEO
Project description:Background and Aims: Telomere dysfunction can increase tumor initiation by induction of chromosomal instability, but initiated tumor cells need to reactivate telomerase for genome stabilization and tumor progression. However, this concept has not been proven in vivo since appropriate mouse models were lacking. Here, we analyzed hepatocarcinogenesis (i) in a novel mouse model of inducible telomere dysfunction on a telomerase-proficient background, (ii) in telomerase knockout mice with chronic telomere dysfunction (G3 mTerc-/-), and (iii) in wild-type mice with functional telomeres and telomerase. Transient or chronic telomere dysfunction enhanced the rates of chromosomal aberrations during hepatocarcinogenesis, but only telomerase-proficient mice exhibited significantly increased rates of macroscopic tumor formation and cancer cell proliferation in response to telomere dysfunction. In contrast, telomere dysfunction resulted in pronounced accumulation of DNA damage, cell cycle arrest and apoptosis in telomerase-deficient liver tumors. Together, these data provide the first in vivo evidence that transient telomere dysfunction during early and late stages of tumorigenesis can promote chromosomal instability and carcinogenesis in telomerase-proficient mice in the absence of additional genetic checkpoint defects at germline level. RNA from liver tumors derived from from DEN treated TTD+ mice TTD- mice and RNA from normal liver 48h-72h after doxycycline induced transient telomere dysfunction in TTD+ and TTD- liver were isolated and RNA was extracted. Agilent Mouse 4x44K v2 arrays were used. DNA from liver tumors and corrresponding kidney as control derived from from DEN treated TTD+ mice, TTD- mice and mTERC-/- G3 mice was isolated and extracted using Phenol/Chloroform. Agilent Mouse 4x44K and Mouse 1x244K arrays were used.
2012-03-30 | E-GEOD-36813 | biostudies-arrayexpress
Project description:We performed single-molecule telomere length and telomere fusion analysis in patients at different stages of chronic lymphocytic leukaemia (CLL). Our work identified the shortest telomeres ever recorded in primary human tissue reinforcing the concept that there is significant cell division in CLL. Furthermore, we provide direct evidence that critical telomere shortening, dysfunction and fusion contribute to disease progression. The frequency of short telomeres and fusion events increased with advanced disease, but importantly these were also found in a subset of early-stage patient samples indicating that these events can precede disease progression. Sequence analysis of fusion events isolated from individuals with the shortest telomeres revealed limited numbers of repeats at the breakpoint, sub-telomeric deletion and microhomology. Array-CGH analysis of individuals displaying evidence of telomere dysfunction revealed large-scale genomic rearrangements that were concentrated in the telomeric regions; this was not observed in samples with longer telomeres. Array CGH was undertaken on six individuals (five CLL stage C and one stage A) that displayed evidence of telomere dysfunction, and four (three CLL stage A and one stage B) that displayed longer and apparently stable telomeres.
2010-05-28 | E-GEOD-22016 | biostudies-arrayexpress
Project description:Telomere dysfunction induces Sirtuin repression that drives telomere-dependent disease
| PRJNA517700 | ENA
Project description:The telomerase RNA component (TERC) is a critical determinant of cellular self renewal. Poly(A)-specific ribonuclease (PARN) is required for post-transcriptional maturation of TERC. PARN mutations lead to incomplete 3′ end processing and increased destruction of nascent TERC RNA transcripts, resulting in telomerase deficiency and telomere diseases. Here, we determined that overexpression of TERC increased telomere length in PARN-deficient cells and hypothesized that decreasing post-transcriptional 3′ oligo-adenylation of TERC would counteract the deleterious effects of PARN mutations. Inhibition of the noncanonical poly(A) polymerase PAP-associated domain–containing 5 (PAPD5) increased TERC levels in PARN-mutant patient cells. PAPD5 inhibition was also associated with increases in TERC stability, telomerase activity, and telomere elongation. Our results demonstrate that manipulating post-transcriptional regulatory pathways may be a potential strategy to reverse the molecular hallmarks of telomere disease.
2016-08-02 | GSE81507 | GEO
Project description:Abstract: Inflammatory bowel disease (IBD) is a chronic inflammatory condition driven by diverse genetic and nongenetic programs that converge to disrupt immune homeostasis in the intestine. We have reported that, in murine intestinal epithelium with telomere dysfunction, DNA damage-induced activation of ataxia-telangiectasia mutated (ATM) results in ATM-mediated phosphorylation and activation of the YAP1 transcriptional coactivator, which in turn up-regulates pro-IL-18, a pivotal immune regulator in IBD pathogenesis. Moreover, individuals with germline defects in telomere maintenance genes experience increased occurrence of intestinal inflammation and show activation of the ATM/YAP1/pro-IL-18 pathway in the intestinal epithelium. Here, we sought to determine the relevance of the ATM/YAP1/pro-IL-18 pathway as a potential driver of IBD, particularly older-onset IBD. Analysis of intestinal biopsy specimens and organoids from older-onset IBD patients documented the presence of telomere dysfunction and activation of the ATM/YAP1/ precursor of interleukin 18 (pro-IL-18) pathway in the intestinal epithelium. Employing intestinal organoids from healthy individuals, we demonstrated that experimental induction of telomere dysfunction activates this inflammatory pathway.
2021-10-30 | GSE182424 | GEO
Project description:Background and Aims: Telomere dysfunction can increase tumor initiation by induction of chromosomal instability, but initiated tumor cells need to reactivate telomerase for genome stabilization and tumor progression. However, this concept has not been proven in vivo since appropriate mouse models were lacking. Here, we analyzed hepatocarcinogenesis (i) in a novel mouse model of inducible telomere dysfunction on a telomerase-proficient background, (ii) in telomerase knockout mice with chronic telomere dysfunction (G3 mTerc-/-), and (iii) in wild-type mice with functional telomeres and telomerase. Transient or chronic telomere dysfunction enhanced the rates of chromosomal aberrations during hepatocarcinogenesis, but only telomerase-proficient mice exhibited significantly increased rates of macroscopic tumor formation and cancer cell proliferation in response to telomere dysfunction. In contrast, telomere dysfunction resulted in pronounced accumulation of DNA damage, cell cycle arrest and apoptosis in telomerase-deficient liver tumors. Together, these data provide the first in vivo evidence that transient telomere dysfunction during early and late stages of tumorigenesis can promote chromosomal instability and carcinogenesis in telomerase-proficient mice in the absence of additional genetic checkpoint defects at germline level.
2012-03-31 | GSE36813 | GEO