keyword
MENU ▼
Read by QxMD icon Read
search

Telomere reverse transcriptase

keyword
https://www.readbyqxmd.com/read/27900472/tissue-specific-expression-of-telomerase-reverse-transcriptase-gene-variants-in-nicotiana-tabacum
#1
Jana Fišerová Jurečková, Eva Sýkorová, Said Hafidh, David Honys, Jiří Fajkus, Miloslava Fojtová
In tobacco, three sequence variants of the TERT gene have been described. We revealed unbalanced levels of TERT variant transcripts in vegetative tobacco tissues and enhanced TERT transcription and telomerase activity in reproductive tissues. Telomerase is a ribonucleoprotein complex responsible for the maintenance of telomeres, structures delimiting ends of linear eukaryotic chromosomes. In the Nicotiana tabacum (tobacco) allotetraploid plant, three sequence variants (paralogs) of the gene coding for the telomerase reverse transcriptase subunit (TERT) have been described, two of them derived from the maternal N...
November 29, 2016: Planta
https://www.readbyqxmd.com/read/27899638/structure-and-folding-of-the-tetrahymena-telomerase-rna-pseudoknot
#2
Darian D Cash, Juli Feigon
Telomerase maintains telomere length at the ends of linear chromosomes using an integral telomerase RNA (TER) and telomerase reverse transcriptase (TERT). An essential part of TER is the template/pseudoknot domain (t/PK) which includes the template, for adding telomeric repeats, template boundary element (TBE), and pseudoknot, enclosed in a circle by stem 1. The Tetrahymena telomerase holoenzyme catalytic core (p65-TER-TERT) was recently modeled in our 9 Å resolution cryo-electron microscopy map by fitting protein and TER domains, including a solution NMR structure of the Tetrahymena pseudoknot...
November 29, 2016: Nucleic Acids Research
https://www.readbyqxmd.com/read/27895115/shared-subunits-of-tetrahymena-telomerase-holoenzyme-and-replication-protein-a-have-different-functions-in-different-cellular-complexes
#3
Heather E Upton, Henry Chan, Juli Feigon, Kathleen Collins
In most eukaryotes, telomere maintenance relies on telomeric repeat synthesis by a reverse transcriptase named telomerase. To synthesize telomeric repeats, the catalytic subunit telomerase reverse transcriptase (TERT) uses the RNA subunit (TER) as a template. In the ciliate Tetrahymena thermophila,the telomerase holoenzyme consists of TER, TERT, and eight additional proteins including the telomeric-repeat single-stranded DNA binding protein Teb1 and its heterotrimer partners Teb2 and Teb3. Teb1 is paralogous to the large subunit of the general single-stranded DNA binding heterotrimer Replication Protein A (RPA)...
November 28, 2016: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/27893208/enterolactone-reduces-telomerase-activity-and-levels-of-its-catalytic-subunit-in-breast-cancer-cells
#4
Davod Ilbeigi, Mitra Nourbakhsh, Shahnaz Khaghani, Nahid Einollahi, Nejat kheiripour, Zafar Gholinejad, Mohammad Alaee, Mostafa saberian
Background: Dietary consumption of phytoestrogens including lignans are linked to a lower incidence of breast cancer. Since activation of telomerase is crucial for growth of cancer cells, the aim of this study was to examine the effect of enterolactone (ENL) and enterodiol (END) on this enzyme. Methods: MTT assays were performed to determine the effect of different concentrations of ENL and ENL on cell viability and to determine the effective concentrations of these two compounds for inhibition of cell growth...
January 10, 2016: Asian Pacific Journal of Cancer Prevention: APJCP
https://www.readbyqxmd.com/read/27872149/endogenous-tert-n-terminal-tagging-affects-human-telomerase-function-at-telomeres-in-vivo
#5
Kunitoshi Chiba, Jacob M Vogan, Robert A Wu, Manraj S Gill, Xiaozhu Zhang, Kathleen Collins, Dirk Hockemeyer
Telomerase action at telomeres is essential for the immortal phenotype of stem cells and the aberrant proliferative potential of cancer cells. Insufficient telomere maintenance can cause stem cell and tissue failure syndromes, while increased telomerase levels are associated with tumorigenesis. Both pathologies can arise from only small perturbation of telomerase function. To analyze telomerase at its low endogenous expression level, we genetically engineered human pluripotent stem cells (hPSCs) to express various N-terminal fusion proteins of the telomerase reverse transcriptase from its endogenous locus...
November 21, 2016: Molecular and Cellular Biology
https://www.readbyqxmd.com/read/27856756/global-analysis-of-somatic-structural-genomic-alterations-and-their-impact-on-gene-expression-in-diverse-human-cancers
#6
Babak Alaei-Mahabadi, Joydeep Bhadury, Joakim W Karlsson, Jonas A Nilsson, Erik Larsson
Tumor genomes are mosaics of somatic structural variants (SVs) that may contribute to the activation of oncogenes or inactivation of tumor suppressors, for example, by altering gene copy number amplitude. However, there are multiple other ways in which SVs can modulate transcription, but the general impact of such events on tumor transcriptional output has not been systematically determined. Here we use whole-genome sequencing data to map SVs across 600 tumors and 18 cancers, and investigate the relationship between SVs, copy number alterations (CNAs), and mRNA expression...
November 29, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27836952/prevalence-and-characteristics-of-tert-and-terc-mutations-in-suspected-genetic-pulmonary-fibrosis
#7
Raphael Borie, Laure Tabèze, Gabriel Thabut, Hilario Nunes, Vincent Cottin, Sylvain Marchand-Adam, Grégoire Prevot, Abdellatif Tazi, Jacques Cadranel, Herve Mal, Lidwine Wemeau-Stervinou, Anne Bergeron Lafaurie, Dominique Israel-Biet, Clement Picard, Martine Reynaud Gaubert, Stephane Jouneau, Jean-Marc Naccache, Julie Mankikian, Christelle Ménard, Jean-François Cordier, Dominique Valeyre, Marion Reocreux, Bernard Grandchamp, Patrick Revy, Caroline Kannengiesser, Bruno Crestani
Telomerase reverse transcriptase (TERT) or telomerase RNA (TERC) gene mutation is a major monogenic cause of pulmonary fibrosis. Sequencing of TERT/TERC genes is proposed to patients with familial pulmonary fibrosis. Little is known about the possible predictors of this mutation and its impact on prognosis.We retrospectively analysed all the genetic diagnoses made between 2007-2014 in patients with pulmonary fibrosis. We evaluated the prevalence of TERT/TERC disease-associated variant (DAV), factors associated with a DAV, and the impact of the DAV on survival...
December 2016: European Respiratory Journal: Official Journal of the European Society for Clinical Respiratory Physiology
https://www.readbyqxmd.com/read/27821557/telomeres-reproductive-aging-and-genomic-instability-during-early-development
#8
David L Keefe
Implantation rate decreases and miscarriage rate increases with advancing maternal age. The oocyte must be the locus of reproductive aging because donation of oocytes from younger to older women abrogates the effects of aging on fecundity. Nuclear transfer experiments in a mouse model of reproductive aging show that the reproductive aging phenotype segregates with the nucleus rather than the cytoplasm. A number of factors within the nucleus have been hypothesized to mediate reproductive aging, including disruption of cohesions, reduced chiasma, aneuploidy, disrupted meiotic spindles, and DNA damage caused by chronic exposure to reactive oxygen species...
December 2016: Reproductive Sciences
https://www.readbyqxmd.com/read/27814571/telomere-protein-complexes-and-their-role-in-lymphoid-malignancies
#9
Julieta Panero, Patricia Dos Santos, Irma Slavutsky
Telomeres are highly regulated and dynamic complexes that protect the genomic DNA and prevent the end of linear chromosomes from being misrecognized as a broken DNA. Due to the end replication problem, telomeres of somatic cells shorten with each cell division, inducing cell senescence. Telomerase is a reverse transcriptase capable of compensating telomere attrition by adding telomere repeats to the ends of chromosomes. Human telomeres are associated with the shelterin complex which consists of six telomere-associated proteins that specifically bind to telomeric DNA...
January 1, 2017: Frontiers in Bioscience (Scholar Edition)
https://www.readbyqxmd.com/read/27797938/leucocyte-telomere-length-genetic-variants-at-the-tert-gene-region-and-risk-of-pancreatic-cancer
#10
Ying Bao, Jennifer Prescott, Chen Yuan, Mingfeng Zhang, Peter Kraft, Ana Babic, Vicente Morales-Oyarvide, Zhi Rong Qian, Julie E Buring, Barbara B Cochrane, J Michael Gaziano, Edward L Giovannucci, JoAnn E Manson, Kimmie Ng, Shuji Ogino, Thomas E Rohan, Howard D Sesso, Meir J Stampfer, Charles S Fuchs, Immaculata De Vivo, Laufey T Amundadottir, Brian M Wolpin
OBJECTIVE: Telomere shortening occurs as an early event in pancreatic tumorigenesis, and genetic variants at the telomerase reverse transcriptase (TERT) gene region have been associated with pancreatic cancer risk. However, it is unknown whether prediagnostic leucocyte telomere length is associated with subsequent risk of pancreatic cancer. DESIGN: We measured prediagnostic leucocyte telomere length in 386 pancreatic cancer cases and 896 matched controls from five prospective US cohorts...
October 21, 2016: Gut
https://www.readbyqxmd.com/read/27793328/telomere-biology-including-tert-rearrangements-in-neuroblastoma-a-useful-indicator-for-surgical-treatments
#11
Masumi Kawashima, Masato Kojima, Yuka Ueda, Sho Kurihara, Eiso Hiyama
PURPOSE: Our telomere biology study of neuroblastomas (NBLs) has revealed that unfavorable NBLs acquired telomere stabilization by telomerase activation or ALT (alternative lengthening of telomeres). Recently, genomic rearrangements in a region proximal to the telomerase reverse transcriptase (TERT) gene have been discovered in NBLs. In this study, TERT rearrangements were examined in NBLs along with their relationship to other aspects of telomere biology. METHODS: In 121 NBLs, including 67 cases detected by mass-screening whose telomere length, telomerase activity, ALT with ATRX/DAXX alterations, and MYCN amplification were already known, TERT rearrangements were examined using GeneChip SNP arrays...
September 17, 2016: Journal of Pediatric Surgery
https://www.readbyqxmd.com/read/27784441/-studies-on-telomerase-reverse-transcriptase-components-and-liver-cancer
#12
J J Cai, X L Guo
Telomeres are DNA tandem repeats at the ends of chromosomes in eukaryotic cells and play important roles in maintaining the stability and integrity of chromosomes. Telomeres are gradually shortened with cell proliferation, and when they are shortened to a certain length, the cells experience senescence and apoptosis. However, a small number of cells can maintain the length of telomeres and restore their function through related mechanisms (activation of telomerase or other mechanisms), and some cells may even be immortalized...
July 20, 2016: Zhonghua Gan Zang Bing za Zhi, Zhonghua Ganzangbing Zazhi, Chinese Journal of Hepatology
https://www.readbyqxmd.com/read/27779655/human-telomerase-reverse-transcriptase-regulation-by-dna-methylation-transcription-factor-binding-and-alternative-splicing-review
#13
Brittany A Avin, Christopher B Umbricht, Martha A Zeiger
The catalytic subunit of telomerase, human telomerase reverse transcriptase (hTERT), plays an essential role in telomere maintenance to oppose cellular senescence and, is highly regulated in normal and cancerous cells. Regulation of hTERT occurs through multiple avenues, including a unique pattern of CpG promoter methylation and alternative splicing. Promoter methylation affects the binding of transcription factors, resulting in changes in expression of the gene. In addition to expression level changes, changes in promoter binding can affect alternative splicing in a cotranscriptional manner...
October 20, 2016: International Journal of Oncology
https://www.readbyqxmd.com/read/27760777/alternative-lengthening-of-human-telomeres-is-a-conservative-dna-replication-process-with-features-of-break-induced-replication
#14
Fani-Marlen Roumelioti, Sotirios K Sotiriou, Vasiliki Katsini, Maria Chiourea, Thanos D Halazonetis, Sarantis Gagos
Human malignancies overcome replicative senescence either by activating the reverse-transcriptase telomerase or by utilizing a homologous recombination-based mechanism, referred to as alternative lengthening of telomeres (ALT). In budding yeast, ALT exhibits features of break-induced replication (BIR), a repair pathway for one-ended DNA double-strand breaks (DSBs) that requires the non-essential subunit Pol32 of DNA polymerase delta and leads to conservative DNA replication. Here, we examined whether ALT in human cancers also exhibits features of BIR A telomeric fluorescence in situ hybridization protocol involving three consecutive staining steps revealed the presence of conservatively replicated telomeric DNA in telomerase-negative cancer cells...
December 2016: EMBO Reports
https://www.readbyqxmd.com/read/27757766/telomere-length-is-regulated-by-fgf-2-in-human-embryonic-stem-cells-and-affects-the-life-span-of-its-differentiated-progenies
#15
Yu Zou, Huei Jinn Tong, Mingming Li, Kai Soo Tan, Tong Cao
The ability of human embryonic stem cells (hESCs) to proliferate indefinitely is attributed to its high telomerase activity and associated long telomere. However, factors regulating telomere length in hESCs remain largely uncharacterized. The aims of this study were, to identify factors which modulate telomere length of hESCs, and to determine if the telomere length of hESCs influences cellular senescence of its differentiated progeny cells. Telomerase reverse transcriptase (TERT) gene expression, telomerase activity and telomere length of hESCs cultured in different culture systems were compared...
October 18, 2016: Biogerontology
https://www.readbyqxmd.com/read/27746409/an-immortalized-steroidogenic-goat-granulosa-cell-line-as-a-model-system-to-study-the-effect-of-the-endoplasmic-reticulum-er-stress-response-on-steroidogenesis
#16
Diqi Yang, Lei Wang, Pengfei Lin, Tingting Jiang, Nan Wang, Fan Zhao, Huatao Chen, Keqiong Tang, Dong Zhou, Aihua Wang, Yaping Jin
With granulosa and theca cells, the ovaries are responsible for producing oocytes and secreting sex steroids such as estrogen and progesterone. Endoplasmic reticulum stress (ERS) plays an important role in follicle atresia and embryo implantation. In this study, goat granulosa cells were isolated from medium-sized (4-6 mm) healthy follicles. Primary granulosa cells were immortalized by transfection with human telomerase reverse transcriptase (hTERT) to establish a goat granulosa cell line (hTERT-GGCs). These hTERT-GGCs expressed hTERT and had relatively long telomeres at passage 50...
October 15, 2016: Journal of Reproduction and Development
https://www.readbyqxmd.com/read/27726484/forks-in-the-tracks-group-ii-introns-spliceosomes-telomeres-and-beyond
#17
Rajendra Kumar Agrawal, Hong-Wei Wang, Marlene Belfort
Group II introns are large catalytic RNAs that form a ribonucleoprotein (RNP) complex by binding to an intron-encoded protein (IEP). The IEP, which facilitates both RNA splicing and intron mobility, has multiple activities including reverse transcriptase. Recent structures of a group II intron RNP complex and of IEPs from diverse bacteria fuel arguments that group II introns are ancestrally related to eukaryotic spliceosomes as well as to telomerase and viruses. Furthermore, recent structural studies of various functional states of the spliceosome allow us to draw parallels between the group II intron RNP and the spliceosome...
October 11, 2016: RNA Biology
https://www.readbyqxmd.com/read/27696331/tgf-beta-receptor-mediated-telomerase-inhibition-telomere-shortening-and-breast-cancer-cell-senescence
#18
Lucy Cassar, Craig Nicholls, Alex R Pinto, Ruping Chen, Lihui Wang, He Li, Jun-Ping Liu
Human telomerase reverse transcriptase (hTERT) plays a central role in telomere lengthening for continuous cell proliferation, but it remains unclear how extracellular cues regulate telomerase lengthening of telomeres. Here we report that the cytokine bone morphogenetic protein-7 (BMP7) induces the hTERT gene repression in a BMPRII receptor- and Smad3-dependent manner in human breast cancer cells. Chonic exposure of human breast cancer cells to BMP7 results in short telomeres, cell senescence and apoptosis...
September 30, 2016: Protein & Cell
https://www.readbyqxmd.com/read/27694758/study-of-htert-and-histone-3-mutations-in-medulloblastoma
#19
Marta Viana-Pereira, Gisele Caravina Almeida, João Norberto Stavale, Susana Malheiro, Carlos Clara, Patrícia Lobo, José Pimentel, Rui Manuel Reis
Hotspot activating mutations of the telomerase reverse transcriptase (hTERT) promoter region were recently described in several tumor types. These mutations lead to enhanced expression of telomerase, being responsible for telomere maintenance and allowing continuous cell division. Additionally, there are alternative telomere maintenance mechanisms, associated with histone H3 mutations, responsible for disrupting the histone code and affecting the regulation of transcription. Here, we investigated the clinical relevance of these mechanistically related molecules in medulloblastoma...
October 1, 2016: Pathobiology: Journal of Immunopathology, Molecular and Cellular Biology
https://www.readbyqxmd.com/read/27685501/retinal-vascular-tortuosity-and-exudative-retinopathy-in-a-family-with-dyskeratosis-congenita-masquerading-as-familial-exudative-vitreoretinopathy
#20
Aristomenis Thanos, Bozho Todorich, Stephen M Hypes, Yoshihiro Yonekawa, Benjamin Thomas, Sandeep Randhawa, Kimberly A Drenser, Michael T Trese
PURPOSE: To report a novel presentation of dyskeratosis congenita masquerading as familial exudative vitreoretinopathy. METHODS: Observational case series involving single family and literature review. RESULTS: A brother and sister were diagnosed with familial exudative vitreoretinopathy at ages 4 and 2, respectively. Both patients were managed with laser photocoagulation. Eight years after the initial presentation, both siblings developed pancytopenia secondary to bone marrow failure...
September 28, 2016: Retinal Cases & Brief Reports
keyword
keyword
67165
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"