• pathway
  • This DNA repair pathway protects cells against endogenous DNA lesion including single-strand breaks. (nih.gov)
  • The group and collaborators have reported many crystal structures of complexes of rat and human DNA polymerases beta with the two substrates (DNA and dNTP), and have solved the NMR structure of the enzyme's 8 kDa domain that contributes lyase activity in the base excision repair pathway. (nih.gov)
  • For this circumstance, the NHEJ pathway provides a solution for repairing the break and is the main system used to repair DSBs in humans and multicellular eukaryotes. (wikipedia.org)
  • NER is a multi-step pathway that removes a variety of different DNA damages that alter normal base pairing, including both UV-induced damages and bulky chemical adducts. (wikipedia.org)
  • Features of premature aging often occur in individuals with mutational defects in genes specifying protein components of the NER pathway, including those with TTD (see DNA damage theory of aging). (wikipedia.org)
  • cellular
  • In 1996, the group demonstrated that Pol β "knock-out" mouse fibroblast cell lines are deficient in DNA repair and in cellular protection against DNA damaging agents, thus establishing a cellular role for this enzyme. (nih.gov)
  • The group also studies cellular signaling of DNA damage, as the base excision repair machinery interfaces with cell cycle and cell death signaling. (nih.gov)
  • DNA Repair provides a forum for the comprehensive coverage of DNA repair and cellular responses to DNA damage . (elsevier.com)
  • The journal publishes original observations on genetic, cellular, biochemical, structural and molecular aspects of DNA repair, mutagenesis, cell cycle regulation, apoptosis and other biological responses in cells exposed to genomic insult, as well as their relationship to human disease . (elsevier.com)
  • From DNA damage to cellular miscommunication, aging is a mysterious and multifarious process. (the-scientist.com)
  • They then showed that this hybrid nanolabel technique can also be used to examine short or long pieces of DNA in solutions that are comparable to cellular environments. (redorbit.com)
  • Like a mechanic popping the hood of a car to get at a faulty engine, a tumor-suppressing protein allows cellular repair mechanisms to pounce on damaged DNA by overcoming a barrier to DNA access. (redorbit.com)
  • DNA is continuously exposed to many different damaging agents such as environmental chemicals, UV light, ionizing radiation, and reactive cellular metabolites. (hindawi.com)
  • When normal repair processes fail, and when cellular apoptosis does not occur, irreparable DNA damage may occur, including double-strand breaks and DNA crosslinkages (interstrand crosslinks or ICLs). (wikipedia.org)
  • There are several types of damage to DNA due to endogenous cellular processes: oxidation of bases [e.g. 8-oxo-7,8-dihydroguanine (8-oxoG)] and generation of DNA strand interruptions from reactive oxygen species, alkylation of bases (usually methylation), such as formation of 7-methylguanosine, 1-methyladenine, 6-O-Methylguanine hydrolysis of bases, such as deamination, depurination, and depyrimidination. (wikipedia.org)
  • DNA Repair is a peer-reviewed scientific journal that covers cellular responses to DNA damage. (wikipedia.org)
  • CAF-1 (chromatin assembly factor-1) is a complex, including Chaf1a (p150), Chaf1b (p60) and p50 subunits that assembles histone tetramers onto replicating DNA in vitro This complex is histone chaperone involved in creating cellular memory of somatic cell identity - cellular differentiation. (wikipedia.org)
  • NHEJ
  • NHEJ is also used to repair DSBs generated during V(D)J recombination when gene regions are rearranged to create the unique antigen binding sites of antibodies and T-cell receptors. (wikipedia.org)
  • During NHEJ, very short stretches of complementary DNA, 1 bp or more at a time, are hybridized together, and the overhangs are removed. (wikipedia.org)
  • XLF interacts with DNA ligase IV and XRCC4 and is thought to be involved in the end-bridging or ligation steps of NHEJ. (wikipedia.org)
  • These XRCC4-XLF filaments have been proposed to bridge DNA prior to end ligation during NHEJ. (wikipedia.org)
  • strands
  • One of the most potent toxins known acts by welding the two strands of the famous double helix together in a unique fashion which foils the standard repair mechanisms cells use to protect their DNA. (phys.org)
  • Another quality control measure is the enzyme hUNG2, which snips stray Us out of newly copied DNA strands, leaving the resulting holes to be filled by a different repair enzyme. (redorbit.com)
  • There are many types of DNA damage, but DSBs, in particular, are the most harmful as both strands are completely disjointed from the rest of the chromosome. (wikipedia.org)
  • MutL recruits UvrD helicase (DNA Helicase II) to separate the two strands with a specific 3' to 5' polarity. (wikipedia.org)
  • genome
  • One form of gene therapy involves the direct repair of a defective gene, using genome-editing technology such as CRISPR-Cas9. (phys.org)
  • DNA repair refers to a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. (phys.org)
  • The DNA repair ability of a cell is vital to the integrity of its genome and thus to its normal functioning and that of the organism. (phys.org)
  • This breakthrough, which involves hybrid nanomaterials and small angle X-ray scattering (SAXS) technology, has been used to solve a major problem involving genome integrity and the biological detection of mismatched DNA. (redorbit.com)
  • Researchers have long known that DNA's code is made up of four building blocks called nucleotides, commonly abbreviated A, T, G, and C. Before a cell divides, DNA-copying enzymes string these nucleotides together based on existing templates, so that each of the new cells gets its own copy of the genome. (redorbit.com)
  • This is a critical piece of information, Stivers says, because when a retrovirus like HIV invades a cell, its first order of business is to make a DNA copy of its own genome, then insert that copy into the host cell's genome. (redorbit.com)
  • This gene encodes a protein that functions in genome maintenance (double strand break repair). (wikipedia.org)
  • binds
  • MutS forms a dimer (MutS2) that recognises the mismatched base on the daughter strand and binds the mutated DNA. (wikipedia.org)
  • MutH binds at hemimethylated sites along the daughter DNA, but its action is latent, being activated only upon contact by a MutL dimer (MutL2), which binds the MutS-DNA complex and acts as a mediator between MutS2 and MutH, activating the latter. (wikipedia.org)
  • Rare fragile sites (RFSs) are classified into two sub-groups based on the compounds that elicit breakage: folate-sensitive groups (for examples, see ), and nonfolate-sensitive groups, which are induced by bromodeoxyuridine (BrdU) or distamycin A, an antibiotic that preferentially binds to AT-pairs of DNA. (wikipedia.org)
  • gene
  • Johns Hopkins scientists have developed a streamlined method and accompanying efficiency "rules" for introducing new DNA sequences into cells after using the gene-cutting tool known as CRISPR. (phys.org)
  • When CtIP becomes activated, say the scientists, it causes the protein made by the BRCA1 gene to bind to the damaged DNA. (cancerresearchuk.org)
  • When a mutation is present in a DNA repair gene, the repair gene will either not be expressed or be expressed in an altered form. (wikipedia.org)
  • DSBs that are not efficiently repaired may result in the loss of important protein coding genes and regulatory sequences required for gene expression necessary for the life of a cell. (wikipedia.org)
  • DNA repair and recombination protein RAD54-like is a protein that in humans is encoded by the RAD54L gene. (wikipedia.org)
  • However, some tumor cells are able to repair this type of DNA damage, and therefore diminish the therapeutic efficacy of temozolomide, by expressing a protein O6-alkylguanine DNA alkyltransferase (AGT) encoded in humans by the O-6-methylguanine-DNA methyltransferase (MGMT) gene. (wikipedia.org)
  • synthesis
  • the group demonstrated that alteration of key amino acid side chains cripples Pol β so that it no longer catalyzes DNA synthesis efficiently and does not discriminate between correct and incorrect incoming nucleotides. (nih.gov)
  • The group conducts physical, biochemical, cell and molecular biology research on mammalian base excision repair enzymes-in particular, the study of gap-filling DNA synthesis in DNA repair. (nih.gov)
  • During DNA synthesis the newly synthesised (daughter) strand will commonly include errors. (wikipedia.org)
  • enzymes
  • For this reason, one of the most important questions about this category is how much of a difference can DNA repair enzymes make if the system is already well stocked with repair tools? (skininc.com)
  • On of the first enzymes to report DNA repair activity was T4N5. (skininc.com)
  • Our technique of employing SAXS with gold nanolabels allows us to examine DNA processing by cooperative enzymes in which solution conditions, long distances, low concentrations, substoichiometric populations, and short time-scales are of importance," says Greg Hura, a scientist with Berkeley Lab's Physical Biosciences Division. (redorbit.com)
  • DSBs
  • Yet, as cells grow and change, DNA is vulnerable to defects, especially double strand breaks (DSBs). (phys.org)
  • In this study, we report that mutant huntingtin (Htt) expression in neurons causes double-strand breaks (DSBs) of genomic DNA, and Htt further promotes DSBs by impairing DNA repair. (sigmaaldrich.com)
  • One of these include ionizing radiation, such as γ radiation and X-rays, which ionize the deoxyribose groups in the DNA backbone and can induce DSBs. (wikipedia.org)
  • deficient
  • Having shown that BRIT1 deficiency impairs HR repair, Peng said one solution the team is examining is to treat cancer cells lacking BRIT1 with PARP inhibitors, drugs that specifically kill HR-deficient cancer cells. (redorbit.com)
  • meiosis
  • This reduced fertility appears to be due to germ cell attrition resulting from a combination of unrepaired DNA breaks during meiosis and defective synapsis of the X and Y chromosomes. (wikipedia.org)
  • defective
  • It probably has effects on many other cancers as well, because all the cancers are ultimately linked to defective DNA," he said. (redorbit.com)
  • efficiently
  • If your DNA is damaged, the health of replacement cells is compromised, which leads to a body that no longer performs as efficiently and effectively. (skininc.com)
  • Scientist
  • Having made this observation, Lindahl was the first scientist to identify "a completely new group of DNA glycosylases" and described how they functioned in base excision repair in a 1986 paper entitled "DNA Glycosylases in DNA Repair" and published in Mechanisms of DNA Damage and Repair , which has been cited by more than 3,900 other articles in the field, according to Google Scholar. (theregister.co.uk)
  • defects
  • It becomes possible to bend the DNA in places where there are defects. (redorbit.com)
  • DNA repair efficiency dropped by between 40 and 60 percent in cells with BRIT1 knocked down that were then exposed to ionizing radiation, allowing many damaged cells to divide and pass on their genetic defects. (redorbit.com)
  • DNA repair defects can cause an accelerated aging disease or an increased risk of cancer, or sometimes both. (wikipedia.org)
  • DNA repair defects are seen in nearly all of the diseases described as accelerated aging disease, in which various tissues, organs or systems of the human body age prematurely. (wikipedia.org)
  • Ataxia-telangiectasia Bloom syndrome Cockayne syndrome Fanconi anemia Progeria (Hutchinson-Gilford progeria syndrome) Rothmund-Thomson syndrome Trichothiodystrophy Werner syndrome Xeroderma pigmentosum Some examples of DNA repair defects causing progeroid syndromes in humans or mice are shown in Table 1. (wikipedia.org)
  • Homozygotes of both sex had abnormal eye sizes, narrow eye openings, skeletal defects (including scoliosis and fusion of vertebrae), and displayed an increase in DNA instability as shown by a micronucleus test. (wikipedia.org)
  • molecule
  • The system's two vital components are high levels of a molecule that becomes embedded in viral DNA like a code written in invisible ink, and an enzyme that, when it reads the code, switches from repairing the DNA to chopping it up into unusable pieces. (redorbit.com)
  • Elsevier
  • Published monthly since January 2002 by Elsevier, with Errol Friedberg as editor in chief, the journal publishes original research papers, short reviews, and book reviews concerning DNA repair, cell cycle regulation, cell death, and other biological responses to genetic damage. (wikipedia.org)
  • 2016
  • Biogerontology Degenerative disease DNA damage theory of aging Genetic disorder Senescence Park JM, Kang TH (2016). (wikipedia.org)
  • mismatches
  • In a paper published in the Journal of Physical Chemistry B (April 26, 2013), Feig and his research team showed that the identification and initiation of repair depended on how the MutS protein bound with the base mismatches. (redorbit.com)
  • biological
  • The biological information that makes us unique is encoded in our DNA. (redorbit.com)
  • DNA damage is a natural biological occurrence that happens every time cells divide and multiply. (redorbit.com)
  • The biological repair machinery seems to take advantage of this propensity by 'testing' DNA to determine whether it can be bent easily. (redorbit.com)
  • occurs
  • DNA damage occurs frequently and if you couldn't repair your DNA, then you won't live for very long. (redorbit.com)
  • The therapeutic benefit of temozolomide depends on its ability to alkylate/methylate DNA, which most often occurs at the N-7 or O-6 positions of guanine residues. (wikipedia.org)