Consulta: subjectFacets:"DNA repair"
Registros recuperados: 23
Data/hora: 19/05/2024 04:20:20

A model for the RecA protein of Mycoplasma synoviae
Provedor de dados: Genetics and Molecular Biology
Autores: Fonseca,Marbella Maria; Alarcon,Frank J.B.; Vasconcelos,Ana Tereza de; Agnez-Lima,Lucymara Fassarela.
In this work, we predict a structural model for the RecA protein from M. synoviae (MsRecA) by theoretical homology modeling and evaluate the occurrence of polymorphisms in this protein within several isolates of this species. The structural model suggested for MsRecA conserves the main domains present in MtRecA and EcRecA. The L1 and L2 regions showed six and three amino acid substitutions, respectively, which apparently do not affect the conformation and function of MsRecA. The C-terminal domain is shorter than that found in EcRecA and MtRecA, which may increase its capacity to bind dsDNA and displace SSB, compensating the absence of recombination initiation enzymes. The MS59 isolate RecA sequence showed one polymorphism which does not affect its...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA repair; Recombination; RecA; Mycoplasma synoviae.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000200018

A never-ending story: the steadily growing family of the FA and FA-like genes
Provedor de dados: Genetics and Molecular Biology
Autores: Gueiderikh,Anna; Rosselli,Filippo; Neto,Januario B.C.
Abstract Among the chromosome fragility-associated human syndromes that present cancer predisposition, Fanconi anemia (FA) is unique due to its large genetic heterogeneity. To date, mutations in 21 genes have been associated with an FA or an FA-like clinical and cellular phenotype, whose hallmarks are bone marrow failure, predisposition to acute myeloid leukemia and a cellular and chromosomal hypersensitivity to DNA crosslinking agents exposure. The goal of this review is to trace the history of the identification of FA genes, a history that started in the eighties and is not yet over, as indicated by the cloning of a twenty-first FA gene in 2016.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA repair; Leukemia; Fanconi anemia; Chromosomal abnormalities.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572017000300398

ADP-ribosylation: from molecular mechanisms to human disease
Provedor de dados: Genetics and Molecular Biology
Autores: Hoch,Nicolas C.; Polo,Luis M.
Abstract Post-translational modification of proteins by ADP-ribosylation, catalysed by poly (ADP-ribose) polymerases (PARPs) using NAD+ as a substrate, plays central roles in DNA damage signalling and repair, modulates a range of cellular signalling cascades and initiates programmed cell death by parthanatos. Here, we present mechanistic aspects of ADP-ribose modification, PARP activation and the cellular functions of ADP-ribose signalling, and discuss how this knowledge is uncovering therapeutic avenues for the treatment of increasingly prevalent human diseases such as cancer, ischaemic damage and neurodegeneration.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: ADP ribose; PARP; DNA damage response; DNA repair; Parthanatos.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572020000200304

Age-related Changes in DNA Methylation Status of hTERT Gene Promoter of Oral Epithelial Cells
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Bezerra,Stephane Flaviane de Oliveira; Costa,Ludimila de Araújo; Freitas,Priscylla Alves Nascimento de; Oliveira,Naila Francis Paulo de.
The purpose of this study was to investigate the effect of aging on the DNA methylation status of two genes involved in tumorigenesis (telomerase gene hTERT and DNA repair gene- MLH1) and one in metabolism (methylenetetrahydrofolate reductase gene- MTHFR) in oral epithelial cells. DNA methylation analysis was performed by Methylation Sensitive Restriction Enzymes (MSRE) of healthy oral epithelial cells of child (6-10 years, n=21), young (20-25 years, n=19) and elderly (over 60 years, n=25). The results for the hTERT gene showed significant variation in the methylation frequency at CpG dinucleotides among the groups (p=0.0001), with the methylated condition more frequently in children and young people. In relation to MLH1 and MTHFR, no differences were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Epigenetic; DNA methylation; Aging; DNA repair; Telomerase; MTHFR.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132015000100082

Assessment of genetic mutations in the XRCC2 coding region by high resolution melting curve analysis and the risk of differentiated thyroid carcinoma in Iran
Provedor de dados: Genetics and Molecular Biology
Autores: Fayaz,Shima; Fard-Esfahani,Pezhman; Fard-Esfahani,Armaghan; Mostafavi,Ehsan; Meshkani,Reza; Mirmiranpour,Hossein; Khaghani,Shahnaz.
Homologous recombination (HR) is the major pathway for repairing double strand breaks (DSBs) in eukaryotes and XRCC2 is an essential component of the HR repair machinery. To evaluate the potential role of mutations in gene repair by HR in individuals susceptible to differentiated thyroid carcinoma (DTC) we used high resolution melting (HRM) analysis, a recently introduced method for detecting mutations, to examine the entire XRCC2 coding region in an Iranian population. HRM analysis was used to screen for mutations in three XRCC2 coding regions in 50 patients and 50 controls. There was no variation in the HRM curves obtained from the analysis of exons 1 and 2 in the case and control groups. In exon 3, an Arg188His polymorphism (rs3218536) was detected as a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA repair; Gene polymorphism; Mutation analysis.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000100004

Deciphering the molecular adaptation of the king scallop (Pecten maximus) to heat stress using transcriptomics and proteomics
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Artigaud, Sebastien; Richard, Joelle; Thorne, Michael A. S.; Lavaud, Romain; Flye-sainte-marie, Jonathan; Jean, Fred; Peck, Lloyd S.; Clark, Melody S.; Pichereau, Vianney.
Background: The capacity of marine species to survive chronic heat stress underpins their ability to survive warming oceans as a result of climate change. In this study RNA-Seq and 2-DE proteomics were employed to decipher the molecular response of the sub-tidal bivalve Pecten maximus, to elevated temperatures. Results: Individuals were maintained at three different temperatures (15, 21 and 25 degrees C) for 56 days, representing control conditions, maximum environmental temperature and extreme warming, with individuals sampled at seven time points. The scallops thrived at 21 degrees C, but suffered a reduction in condition at 25 degrees C. RNA-Seq analyses produced 26,064 assembled contigs, of which 531 were differentially expressed, with putative...
Tipo: Text
Palavras-chave: Marine biology; Metabolism; DNA repair; Transcription regulation; Apoptosis; Energy reserves.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00301/41173/40360.pdf

Deoxyribonucleic acid damage and repair response in the chemotherapy of lung cancer: cross-sectional study
Provedor de dados: Anais da Academia Brasileira de Ciências
Autores: SCHNEIDER,MARCIA R.; SILVA,ANDRÉA L.G. DA; GOULART,CÁSSIA L.; SCHNEIDERS,PALOMA B.; WEBER,AUGUSTO F.; POSSUELO,LIA G.; VALIM,ANDREIA R.M.
Abstract: This study evaluated 24 patients with lung cancer (CA) and 23 individuals with no smoking history or cancer in the family and without respiratory disease in childhood (CO). Peripheral blood lymphocytes was used to perform alkaline comet assay and to assess DNA damage as well as to evaluate methyl methane sulfonate (MMS) DNA repair after one hour and three hours at 37 ºC. The percentage of residual damage (RD) after three hours of MMS treatment, for each patient was assessed. The majority of patients were in the CA group, male patients, former smokers, with a history of smoking for 15 years and without associated comorbidities. Alkaline and residual damages were higher in the CA group when compared to controls (alkaline damage P = 0.015 and RD P =...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Comet assay; DNA damage; DNA repair; Lung cancer.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000500806

DNA lesions and repair in trypanosomatids infection
Provedor de dados: Genetics and Molecular Biology
Autores: Repolês,Bruno M.; Machado,Carlos Renato; Florentino,Pilar T.V.
Abstract Pathological processes such as bacterial, viral and parasitic infections can generate a plethora of responses such as, but not restricted to, oxidative stress that can be harmful to the host and the pathogen. This stress occurs when there is an imbalance between reactive oxygen species produced and antioxidant factors produced in response to the infection. This imbalance can lead to DNA lesions in both infected cells as well as in the pathogen. The effects of the host response on the parasite lead to several kinds of DNA damage, causing alterations in the parasite’s metabolism; the reaction and sensitivity of the parasite to these responses are related to the DNA metabolism and life cycle of each parasite. The present review will discuss the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Trypanosoma cruzi; Reactive oxygen species; DNA repair.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572020000200311

DNA repair diseases: what do they tell us about cancer and aging?
Provedor de dados: Genetics and Molecular Biology
Autores: Menck,Carlos FM; Munford,Veridiana.
The discovery of DNA repair defects in human syndromes, initially in xeroderma pigmentosum (XP) but later in many others, led to striking observations on the association of molecular defects and patients' clinical phenotypes. For example, patients with syndromes resulting from defective nucleotide excision repair (NER) or translesion synthesis (TLS) present high levels of skin cancer in areas exposed to sunlight. However, some defects in NER also lead to more severe symptoms, such as developmental and neurological impairment and signs of premature aging. Skin cancer in XP patients is clearly associated with increased mutagenesis and genomic instability, reflecting the defective repair of DNA lesions. By analogy, more severe symptoms observed in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Xeroderma pigmentosum; Ultraviolet; DNA damage; Oxidative stress; DNA repair.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572014000200008

DNA repair genes in astrocytoma tumorigenesis, progression and therapy resistance
Provedor de dados: Genetics and Molecular Biology
Autores: Sousa,Juliana Ferreira de; Serafim,Rodolfo Bortolozo; Freitas,Laura Marise de; Fontana,Carla Raquel; Valente,Valeria.
Abstract Glioblastoma (GBM) is the most common and malignant type of primary brain tumor, showing rapid development and resistance to therapies. On average, patients survive 14.6 months after diagnosis and less than 5% survive five years or more. Several pieces of evidence have suggested that the DNA damage signaling and repair activities are directly correlated with GBM phenotype and exhibit opposite functions in cancer establishment and progression. The functions of these pathways appear to present a dual role in tumorigenesis and cancer progression. Activation and/or overexpression of ATRX, ATM and RAD51 genes were extensively characterized as barriers for GBM initiation, but paradoxically the exacerbated activity of these genes was further associated...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glioblastoma; DNA repair; Biomarkers; Tumor progression; Therapy resistance.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572020000200306

Evaluation of radioinduced damage and repair capacity in blood lymphocytes of breast cancer patients
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Nascimento,P.A.; da Silva,M.A.; Oliveira,E.M.; Suzuki,M.F.; Okazaki,K.
Genetic damage caused by ionizing radiation and repair capacity of blood lymphocytes from 3 breast cancer patients and 3 healthy donors were investigated using the comet assay. The comets were analyzed by two parameters: comet tail length and visual classification. Blood samples from the donors were irradiated in vitro with a 60Co source at a dose rate of 0.722 Gy/min, with a dose range of 0.2 to 4.0 Gy and analyzed immediately after the procedure and 3 and 24 h later. The basal level of damage and the radioinduced damage were higher in lymphocytes from breast cancer patients than in lymphocytes from healthy donors. The radioinduced damage showed that the two groups had a similar response when analyzed immediately after the irradiations. Therefore, while...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Comet assay; DNA damage; DNA repair; Ionizing radiation; Breast cancer; Blood lymphocytes.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000200003

Expression of the bacterial recA gene impairs genetic recombination and sporulation in a Saccharomyces cerevisiae diploid strain
Provedor de dados: Genetics and Molecular Biology
Autores: Morais Junior,Marcos Antonio de; Santos,José Ferreira dos; Henriques,João Antonio Pegas.
The Escherichia coli RecA protein (RecAp) has been demonstrated to induce mutagenesis in yeast cells, although there is still little information on the role of the RecAp in yeast recombination events. We evaluated spontaneous and induced general recombination in vegetative and meiotic cells of the XS2316 strain of the yeast Saccharomyces cerevisiae bearing the recA gene. We found that RecAp decreased reciprocal recombination, gene conversion and intrachromosomal recombination and promoted an increase in error-prone processes in both vegetative and meiotic cells, while its negative effect on meiotic recombination blocked ascospore formation.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA repair; Genetic recombination; RecA gene; Sporulation; Yeast.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000200016

From Gene Targeting to Genome Editing: Transgenic animals applications and beyond
Provedor de dados: Anais da Academia Brasileira de Ciências
Autores: ROCHA-MARTINS,MAURÍCIO; CAVALHEIRO,GABRIEL R.; MATOS-RODRIGUES,GABRIEL E.; MARTINS,RODRIGO A.P.
ABSTRACTGenome modification technologies are powerful tools for molecular biology and related areas. Advances in animal transgenesis and genome editing technologies during the past three decades allowed systematic interrogation of gene function that can help model how the genome influences cellular physiology. Genetic engineering via homologous recombination (HR) has been the standard method to modify genomic sequences. Nevertheless, nuclease-guided genome editing methods that were developed recently, such as ZFN, TALEN and CRISPR/Cas, opened new perspectives for biomedical research. Here, we present a brief historical perspective of genome modification methods, focusing on transgenic mice models. Moreover, we describe how new techniques were discovered...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Homologous recombination; DNA repair; Cre-LoxP; ZFN; TALEN; CRISPR/Cas9.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000301323

High expression of the circadian gene mPer2 diminishes the radiosensitivity of NIH 3T3 cells
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Chang,L.; Liu,Y.Y.; Zhu,B.; Li,Y.; Hua,H.; Wang,Y.H.; Zhang,J.; Jiang,Z.; Wang,Z.R.
Period2 is a core circadian gene, which not only maintains the circadian rhythm of cells but also regulates some organic functions. We investigated the effects of mPeriod2 (mPer2) expression on radiosensitivity in normal mouse cells exposed to 60Co-γ-rays. NIH 3T3 cells were treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) to induce endogenous mPer2 expression or transfected with pcDNA3.1(+)-mPer2 and irradiated with 60Co-γ-rays, and then analyzed by several methods such as flow cytometry, colony formation assay, RT-PCR, and immunohistochemistry. Flow cytometry and colony formation assay revealed that irradiated NIH 3T3 cells expressing high levels of mPer2 showed a lower death rate (TPA: 24 h 4.3% vs 12 h 6.8% and control 9.4%; transfection:...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Circadian; MPer2; Radiation; Cell death; Proliferation; DNA repair.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009001000003

Identification in silico of putative damage responsive elements (DRE) in promoter regions of the yeast genome
Provedor de dados: Genetics and Molecular Biology
Autores: Silva,Walkiria Luckwu de Santana; Cavalcanti,Andre Ricardo de Oliveira; Guimarães,Katia Silva; Morais Jr.,Marcos Antonio de.
We report an in silico analysis to identify nucleotide sequence motifs in DNA repair genes that may define a binding site for regulatory proteins during the induction of those genes by mutagens. The damage responsive elements (DRE) weight matrix generated in this analysis was used to search for homologous sequences in the promoter region of all genes, including putative gene and hypothetical open reading frames (ORFs), in the Saccharomyces Genome Data Base (SGD). The results demonstrated that over one third of the yeast genes in the database presented at least one 15-bp sequence in their promoter region with 85% or more of similarity to the DRE consensus sequence. The presence of the DRE sequence in the promoter region of regulatory genes and its high...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA binding site; DNA repair; Gene promoter; Gene regulation; Transfac; Weight matrix.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000500025

Induction and elimination of bulky benzo[a]pyrene-related DNA adducts and 8-oxodGuo in mussels Mytilus galloprovincialis exposed in vivo to B[a]P-contaminated feed
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Akcha, Farida; Burgeot, Thierry; Budzinski, H; Pfohla Leszkowicz, A; Narbonne, J.
With the aim of developing biomarkers of polycyclic aromatic hydrocarbon (PAH) genotoxicity for biomonitoring of the marine environment, the formation of DNA adducts and oxidative DNA damage was studied in the sentinel organism Mytilus. Mussels M. galloprovincialis were exposed for 21 d to different doses of benzo[a]pyrene (B[a]P) (50 and 100 mg B[a]P kg(-1) dry wt mussel d(-1)) via trophic intake. The kinetics of B[a]P concentration in whole mussel tissues was determined in both groups, and a dose-response study was conducted for both gill B[a]P-related DNA adducts and 8-oxo-7, 8-dihydro-2'-deoxyguanosine (8-oxodGuo) formation in gill and digestive gland DNA. Exposure was followed by a 10 d depuration period to study mussel recovery. Although B[a]P was...
Tipo: Text
Palavras-chave: DNA repair; 8 oxodGuo; DNA adducts; Mussel; BaP.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-813.pdf

Non-homologous DNA end joining in normal and cancer cells and its dependence on break structures
Provedor de dados: Genetics and Molecular Biology
Autores: Poplawski,Tomasz; Pastwa,Elzbieta; Blasiak,Janusz.
DNA double-strand breaks (DSBs) are a serious threat to the cell, for if not or miss-repaired, they can lead to chromosomal aberration, mutation and cancer. DSBs in human cells are repaired via non-homologous DNA end joining (NHEJ) and homologous recombination repair pathways. In the former process, the structure of DNA termini plays an important role, as does the genetic constitution of the cells, through being different in normal and pathological cells. In order to investigate the dependence of NHEJ on DSB structure in normal and cancer cells, we used linearized plasmids with various, complementary or non-complementary, single-stranded or blunt DNA termini, as well as whole-cell extract isolated from normal human lymphocytes, chronic myeloid leukemia...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA repair; Non-homologous DNA end joining; DNA double-strand breaks; Complementary and non-complementary DNA ends.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200027

Polymorphisms of the DNA repair genes XRCC1 and XRCC3 in a Brazilian population
Provedor de dados: Genetics and Molecular Biology
Autores: Duarte,Márcia Cristina; Colombo,Jucimara; Rossit,Andréa Regina Baptista; Silva,Ana Elizabete.
In several DNA repair genes, polymorphisms may result in reduced repair capacity, which has been implicated as a risk factor for various types of cancer. The frequency of the polymorphic alleles varies among populations, suggesting an ethnic distribution of genotypes. We genotyped 300 healthy Southeastern Brazilian individuals (262 of European ancestry and 38 of African ancestry) for polymorphisms of codons 194 and 399 of the XRCC1 base excision repair pathway gene and of codon 241 of the XRCC3 homologous recombination repair pathway gene. The allele frequencies were 0.07 for the Arg194Trp and 0.33 for the Arg399Gln codons of the XRCC1 gene and 0.35 for the Thr241Met codon of the XRCC3 gene. The genotypic frequencies were within Hardy-Weinberg equilibrium....
Tipo: Info:eu-repo/semantics/other
Palavras-chave: DNA repair; XRCC1; XRCC3; Polymorphism; Ethnic variability.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000300011

Relationship between XPD, RAD51, and APEX1 DNA repair genotypes and prostate cancer risk in the male population of Rio de Janeiro, Brazil
Provedor de dados: Genetics and Molecular Biology
Autores: Cypriano,Ana Sheila; Alves,Gilda; Ornellas,Antonio Augusto; Scheinkman,José; Almeida,Renata; Scherrer,Luciano; Lage,Claudia.
Abstract Susceptibility to cancer ensues in individuals carrying malfunctioning DNA repair mechanisms. The impact of Single Nucleotide Polymorphisms (SNPs) in key DNA repair mechanisms on risk for prostate cancer was investigated in this case-control study. Samples consisted of 110 patients with confirmed prostate cancer and 200 unaffected men, from Rio de Janeiro, Brazil. XPD/Lys751Gln (rs13181), APEX1/Asp148Glu (rs1130409), and RAD51/G135C (rs1801320) SNPs were analyzed by PCR-RFLP. Allelic and genotypic frequencies were calculated and compared by Chi-Square test. The association between SNPs and clinical/epidemiological data was considered significant by Odds Ratio analysis, with IC95% and a p-value≤0.05. Only the XPD/Lys751Gln SNP significantly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Prostate cancer; Single nucleotide polymorphism; XPD; DNA repair; Gene-environment interaction.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572017000500751

Relationships between chromatin remodeling and DNA damage repair induced by 8-methoxypsoralen and UVA in yeast Saccharomyces cerevisiae
Provedor de dados: Genetics and Molecular Biology
Autores: Cruz,Lavínia Almeida; Guecheva,Temenouga Nikolova; Bonato,Diego; Henriques,João Antônio Pêgas.
Eukaryotic cells have developed mechanisms to prevent genomic instability, such as DNA damage detection and repair, control of cell cycle progression and cell death induction. The bifunctional compound furocumarin 8-methoxy-psoralen (8-MOP) is widely used in the treatment of various inflammatory skin diseases. In this review, we summarize recent data about the role of chromatin remodeling in the repair of DNA damage induced by treatment with 8-methoxypsoralen plus UVA (8-MOP+UVA), focusing on repair proteins in budding yeast Saccharomyces cerevisiae, an established model system for studying DNA repair pathways. The interstrand crosslinks (ICL) formed by the 8-MOP+UVA treatment are detrimental lesions that can block transcription and replication, leading to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA repair; Psoralen; Chromatin remodeling; Histones; DNA interstrand cross-links.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000600021

Role of RadA and DNA Polymerases in Recombination-Associated DNA Synthesis in Hyperthermophilic Archaea
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Hogrel, Gaelle; Lu, Yang; Alexandre, Nicolas; Bossé, Audrey; Dulermo, Remi; Ishino, Sonoko; Ishino, Yoshizumi; Flament, Didier.
Among the three domains of life, the process of homologous recombination (HR) plays a central role in the repair of double-strand DNA breaks and the restart of stalled replication forks. Curiously, main protein actors involved in the HR process appear to be essential for hyperthermophilic Archaea raising interesting questions about the role of HR in replication and repair strategies of those Archaea living in extreme conditions. One key actor of this process is the recombinase RadA, which allows the homologous strand search and provides a DNA substrate required for following DNA synthesis and restoring genetic information. DNA polymerase operation after the strand exchange step is unclear in Archaea. Working with Pyrococcus abyssi proteins, here we show...
Tipo: Text
Palavras-chave: Homologous recombination; Archaea; DNA polymerase; Recombinase; DNA repair.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00641/75274/75539.pdf

Structure and function of a novel endonuclease acting on branched DNA substrates
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Ren, Bin; Kuehn, Joelle; Meslet-cladiere, Laurence; Briffotaux, Julien; Norais, Cedric; Lavigne, Regis; Flament, Didier; Ladenstein, Rudolf; Myllykallio, Hannu.
We show that Pyrococcus abyssi PAB2263 (dubbed NucS (nuclease for ss DNA) is a novel archaeal endonuclease that interacts with the replication clamp PCNA. Structural determination of P. abyssi NucS revealed a two-domain dumbbell-like structure that in overall does not resemble any known protein structure. Biochemical and structural studies indicate that NucS orthologues use a non-catalytic ssDNA-binding domain to regulate the cleavage activity at another site, thus resulting into the specific cleavage at double-stranded DNA (dsDNA)/ssDNA junctions on branched DNA substrates. Both 3' and 5' extremities of the ssDNA can be cleaved at the nuclease channel that is too narrow to accommodate duplex DNA. Altogether, our data suggest that NucS proteins constitute...
Tipo: Text
Palavras-chave: Structure function studies; RecB family; Novel endonuclease; DNA repair; Branched DNA structures.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6807.pdf

uvsZ1 mutation shows epistatic relations with uvsD153 and uvsJ1 mutations without any involvement with checkpoint control in Aspergillus nidulans
Provedor de dados: Biological Research
Autores: BAPTISTA,FRANCIELLE; AVEZUM ALVES DE CASTRO-PRADO,MARIALBA.
The participation of the recently described uvsZ1 mutation in checkpoint control and the identification of epistatic relations between uvsZ1 mutation and uvsD153 and uvsJ1 mutations are provided. The effect of mutation uvsZ1 in mitotic exchanges into paba-bi (chromosome I) and cho-nic (chromosome VII) genetic intervals has also been evaluated. The mutation uvsZ1 was epistatic with regard to uvsD153 and uvsJ1 mutations, with no involvement with checkpoint control. In contrast to mutations in UvsB and UvsF groups, the uvsZ1 mutation failed to cause any changes in the frequencies of mitotic crossing-over. The distinct phenotypic traits given by mutation uvsZ1 suggest the presence of complex interactions among the different DNA repair pathways. Interaction may...
Tipo: Journal article
Palavras-chave: Checkpoint pathways; DNA repair; Uvs mutations.
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000300018