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  • strongly
  • New small molecules having modified acceptor strength and π-conjugation length and containing dicyanovinylene (DCV) and tricyanovinylene (TCV) as a strongly electron-accepting unit with indacenodithiophene, IDT(DCV)2, IDT(TCV)2, and IDTT(TCV. (korea.ac.kr)
  • cells
  • Accumulated breaks in DNA prevent cells from entering into the mitotic phase of the cell cycle, and lead to cell death. (drugbank.ca)
  • Teniposide is a phase-specific cytotoxic drug, acting in the late S or early G 2 phase of the cell cycle, thus preventing cells from entering mitosis. (drugbank.ca)
  • The cytotoxic effects of teniposide are related to the relative number of double-stranded DNA breaks produced in cells, which are a reflection of the stabilization of a topoisomerase II-DNA intermediate. (drugbank.ca)
  • protein
  • We transfected HeLa cells with small interfering RNAs (siRNAs) targeted against either topo IIα or IIβ, and succeeded in knocking down the expression of the corresponding protein. (biologists.org)
  • p>This indicates the type of evidence that supports the existence of the protein. (uniprot.org)
  • The capsid has 2, 3 and 5 fold axis of symmetry with 20 equilateral triangle faces composing of protein subunits. (wikipedia.org)
  • A large part of DNA (more than 98% for humans) is non-coding, meaning that these sections do not serve as patterns for protein sequences. (wikipedia.org)
  • cleavage
  • The complex promotes relaxation of negative and positive supercoiled DNA and DNA decatenation through cleavage and ligation cycles. (genecards.org)
  • The Top1-DNA intermediates, known as cleavage complexes, are transient and at low levels under normal circumstances. (wikipedia.org)
  • Prokaryotes have the ATPase domain and the Toprim fold on one polypeptide, while the DNA cleavage core and the CTD lies on a second polypeptide. (wikipedia.org)
  • Gene
  • DNA topoisomerase 2-alpha is an enzyme that in humans is encoded by the TOP2A gene. (wikipedia.org)
  • Two forms of this enzyme exist as likely products of a gene duplication event. (wikipedia.org)
  • Supercoiling is important in a number of biological processes, such as compacting DNA, and by regulating access to the genetic code, DNA supercoiling strongly affects DNA metabolism and possibly gene expression. (wikipedia.org)
  • DNA supercoiling is important for DNA packaging within all cells, and seems to also play a role in gene expression. (wikipedia.org)
  • knotted DNA molecules
  • Using numerical simulations, we compare properties of knotted DNA molecules that are either torsionally relaxed or supercoiled. (epfl.ch)
  • negatively supercoiled
  • A negatively supercoiled DNA molecule will produce either a one-start left-handed helix, the toroid, or a two-start right-handed helix with terminal loops, the plectoneme. (wikipedia.org)
  • Topoisomerase IV can unknot right-handed knots and decatenate right-handed catenanes without acting on right-handed plectonemes in negatively supercoiled DNA molecules, based on geometrical specificity of juxtapositions. (wikipedia.org)
  • molecules
  • We observe that DNA supercoiling tightens knotted portions of DNA molecules and accentuates the difference in curvature between knotted and unknotted regions. (epfl.ch)
  • The supercoiling-induced tightening of DNA knots observed here shows that torsional tension in DNA may serve to expose DNA knots to the unknotting action of type IIA topoisomerases, and thus explains how these topoisomerases could maintain a low knotting equilibrium in vivo, even for long DNA molecules. (epfl.ch)
  • Based on the properties of intercalating molecules i.e., fluorescing upon binding to DNA and unwinding of DNA base-pairs, recently a single-molecule technique has been introduced to directly visualize individual plectonemes along supercoiled DNA which would further allow to study the interactions of DNA processing proteins with supercoiled DNA. (wikipedia.org)
  • In that study, Sytox Orange (an intercalating dye), has been used to induce supercoiling on surface tethered DNA molecules. (wikipedia.org)
  • Reactions involving the increase in supercoiling require two molecules of ATP. (wikipedia.org)
  • Although each individual nucleotide repeating unit is very small, DNA polymers can be very large molecules containing millions to hundreds of millions of nucleotides. (wikipedia.org)
  • binds
  • This could occur through an active process, where an enzyme binds to the DNA and then facilitates rotation of the base, or a passive process, where the base rotates out spontaneously, and this state is recognized and bound by an enzyme. (wikipedia.org)
  • complexes
  • Crystal structures of human topoisomerase I in covalent and noncovalent complexes with DNA. (ebi.ac.uk)
  • However, treatment with Top1 inhibitors, such as the camptothecins, stabilize the cleavable complexes, prevent DNA religation and induce lethal DNA strand breaks. (wikipedia.org)
  • In contrast to the camptothecins, the indenoisoquinolines are: 1) chemically stable in blood, 2) inhibitors of Top1 cleavable complexes at distinct sites, 3) not substrates of membrane transporters, and 4) more effective as anti-tumor agents in animal models. (wikipedia.org)
  • citation needed] Indenoisoquinolines (green) form a ternary complexes of Top1 (brown) and DNA (blue) (Pommier et al. (wikipedia.org)
  • In absence of the antitoxin, the CcdB poison traps DNA-gyrase cleavable complexes, inducing breaks into DNA and cell death. (wikipedia.org)
  • circular
  • Type IA topoisomerases change the linking number of a circular DNA strand by units of strictly 1. (wikipedia.org)
  • If a DNA segment under twist strain were closed into a circle by joining its two ends and then allowed to move freely, the circular DNA would contort into a new shape, such as a simple figure-eight. (wikipedia.org)
  • The simple figure eight is the simplest supercoil, and is the shape a circular DNA assumes to accommodate one too many or one too few helical twists. (wikipedia.org)
  • Lobal contortions of a circular DNA, such as the rotation of the figure-eight lobes above, are referred to as writhe. (wikipedia.org)
  • The EhV-86 coccolithovirus is suggested to have both linear and circular genomes at different phases during DNA packaging. (wikipedia.org)
  • strand
  • Top1 generates DNA single-strand breaks that allow rotation of the cleaved strand around the double helix axis. (wikipedia.org)
  • Top1 also religates the cleaved strand to reestablish intact duplex DNA. (wikipedia.org)
  • The break is then separated, using domain II as a hinge, and a second duplex or strand of DNA is passed through. (wikipedia.org)
  • DNA supercoiling refers to the over- or under-winding of a DNA strand, and is an expression of the strain on that strand. (wikipedia.org)
  • Like gyrase, topoisomerase IV is able to pass one double-strand of DNA through another double-strand of DNA, thereby changing the linking number of DNA by two in each enzymatic step. (wikipedia.org)
  • DNA can have mutations that cause a base in the DNA strand to be damaged. (wikipedia.org)
  • The uracil base is flipped out into the glycosylase active pocket where it is removed from the DNA strand. (wikipedia.org)
  • It can be thought of as a hand that grips the DNA single strand template. (wikipedia.org)
  • encodes
  • The ccd system (control of cell death) of the F plasmid encodes two proteins, the CcdB toxin (101 amino acids) and the CcdA antidote (72 amino acids). (wikipedia.org)
  • Overlapping
  • Thirty-nine contigs, overlapping DNA fragments, greater in size than 200 base pairs were observed in strain VK. (wikipedia.org)
  • nuclear
  • DNA packaging is greatly increased during nuclear division events such as mitosis or meiosis, where DNA must be compacted and segregated to daughter cells. (wikipedia.org)
  • reaction
  • Additionally it catalyzes both the pyrophosphorolysis of DNA, a reaction which is the reverse of polymerization, and pyrophosphate exchange which represents a repetitive sequence of nucleotide addition and pyrophosphorolysis. (thefreedictionary.com)
  • Base flipping was first observed in 1994 when researchers Klimasauskas, Kumar, Roberts, and Cheng used X-ray crystallography to view an intermediate step in the chemical reaction of a methyltransferase bound to DNA. (wikipedia.org)
  • polymerases
  • This was subsequently confirmed by analysis of their B-family DNA polymerases, which indicated that members of the Phycodnaviridae are more closely related to one another, in comparison to other dsDNA viruses, forming a monophyletic group. (wikipedia.org)
  • proteins
  • The degree of compaction results from the level of DNA-supercoiling and the presence of nucleoid-binding proteins. (frontiersin.org)
  • Transcriptomic studies on the human pathogen Streptococcus pneumoniae , which has a relatively small genome (∼2 Mb) and few nucleoid-binding proteins, have been performed under conditions of local and global changes in supercoiling. (frontiersin.org)
  • alongside proteins, lipids and complex carbohydrates (polysaccharides), they are one of the four major types of macromolecules that are essential for all known forms of life. (wikipedia.org)
  • Reactions
  • There continues to be considerable debate as to whether or not this DNA damage is to be considered one of the mechanisms of action concerning the severe adverse reactions experienced by some patients following fluoroquinolone therapy. (wikipedia.org)
  • molecular
  • DNA is used by researchers as a molecular tool to explore physical laws and theories, such as the ergodic theorem and the theory of elasticity. (wikipedia.org)
  • 1994
  • It was first observed in 1994 using X-ray crystallography in a methyltransferase enzyme catalyzing methylation of a cytosine base in DNA. (wikipedia.org)
  • mitosis
  • Following chromosome segregation at mitosis, the sister cells express two different and complementary mating‐type alleles ( Arcangioli and Thon, 2003 ). (embopress.org)
  • There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis. (wikipedia.org)
  • Higher animals have three distinct forms of such cell divisions: Meiosis I and meiosis II are specialized forms of cell division occurring during generation of gametes (eggs and sperm) for sexual reproduction, mitosis is the form of cell division used by all other cells of the body. (wikipedia.org)
  • Similar to the segregation events of mitosis, the pairs of sister chromatids resulting from the separation of bivalents in meiosis I are further separated in anaphase of meiosis II. (wikipedia.org)
  • Meiosis II-nondisjunction may also result in aneuploidy syndromes, but only to a much smaller extent than do segregation failures in meiosis I. Division of somatic cells through mitosis is preceded by replication of the genetic material in S phase. (wikipedia.org)
  • Chromosome nondisjunction in mitosis can be atrributed to the inactivation of topoisomerase II, condensin, or separase. (wikipedia.org)
  • DNA packaging is greatly increased during nuclear division events such as mitosis or meiosis, where DNA must be compacted and segregated to daughter cells. (wikipedia.org)
  • sequence
  • DNA ATLAS is a free plasmid mapping tool to show features such as promoters, markers, restriction sites and open reading frames in any DNA vector sequence. (wikipedia.org)
  • The TATA box is considered a non-coding DNA sequence (also known as a cis-regulatory element). (wikipedia.org)
  • Classical views have attributed phenotypic variation to differences in primary DNA structure, be it through aberrant mutation or an inherited sequence allele. (wikipedia.org)
  • Genomic modifications that alter gene expression that cannot be attributed to modification of the primary DNA sequence and that are heritable mitotically and meiotically are classified as epigenetic modifications. (wikipedia.org)
  • Daughter cells that inherit these wrong bases carry mutations from which the original DNA sequence is unrecoverable (except in the rare case of a back mutation, for example, through gene conversion). (wikipedia.org)
  • Every base substitution was performed on each of the thirteen nucleotides within the FRT site (example G to A, T, and C). First, the authors showed that most mutations within the FRT sequence cause minimal effects if present within only one of the two sites. (wikipedia.org)
  • synthesis
  • Catalyzes the condensation reaction of fatty acid synthesis by the addition to an acyl acceptor of two carbons from malonyl-ACP. (string-db.org)
  • Ribonucleotide reductases (RNR) catalyze the last step of deoxyribonucleotide synthesis, and are therefore essential to DNA-based life. (ibecbarcelona.eu)
  • Thereby, we show that the two-component system AlgZR, which is crucial for bacterial conversion to the mucoid phenotype associated with chronic disease, controls the RNR network and directs how the DNA synthesis pathway is modulated in mucoid and non-mucoid biofilms, allowing it to respond to oxidative stress. (ibecbarcelona.eu)
  • This hydrolysis drives DNA synthesis to completion. (wikipedia.org)
  • It is thus involved in maintaining cellular guanine deoxy- and ribonucleotide pools needed for DNA and RNA synthesis. (wikipedia.org)
  • molecule
  • Many of these lesions cause structural damage to the DNA molecule and can alter or eliminate the cell's ability to transcribe the gene that the affected DNA encodes. (wikipedia.org)
  • Like other large molecules and biopolymers, DNA often exists in multiple stable geometries (that is, it exhibits conformational isomerism) and configurational, quantum states which are close to each other in energy on the potential energy surface of the DNA molecule. (wikipedia.org)
  • A negatively supercoiled DNA molecule will produce either a one-start left-handed helix, the toroid, or a two-start right-handed helix with terminal loops, the plectoneme. (wikipedia.org)
  • Based on the properties of intercalating molecules i.e., fluorescing upon binding to DNA and unwinding of DNA base-pairs, recently a single-molecule technique has been introduced to directly visualize individual plectonemes along supercoiled DNA which would further allow to study the interactions of DNA processing proteins with supercoiled DNA. (wikipedia.org)
  • plasmid
  • It is analogous to Cre-lox recombination but involves the recombination of sequences between short flippase recognition target (FRT) sites by the recombinase flippase(Flp)derived from the 2 µm plasmid of baker's yeast Saccharomyces cerevisiae. (wikipedia.org)
  • In prokaryotes RecQ is necessary for plasmid recombination and DNA repair from UV-light, free radicals, and alkylating agents. (wikipedia.org)
  • metabolism
  • Folic acid, a vitamin crucial for DNA metabolism (he did not know the significance of DNA at that time), had been discovered by Lucy Wills, when she was working in India, in 1937. (wikipedia.org)
  • Supercoiling is important in a number of biological processes, such as compacting DNA, and by regulating access to the genetic code, DNA supercoiling strongly affects DNA metabolism and possibly gene expression. (wikipedia.org)
  • ligase
  • DNA2.0 developed the Electra Vector System, a universal cloning system that utilizes the type IIS restriction enzyme SapI and T4 DNA ligase in a single-tube reaction. (wikipedia.org)
  • WRN also physically interacts with the major NHEJ factor X4L4 (XRCC4-DNA ligase 4 complex). (wikipedia.org)
  • 1998
  • F. Xuqing and L. Dewei, "Enhancement of shikonin production in cell suspension cultures of Arnebia euchroma employing two-liquid-phase systems," Chinese Journal of Chemical Engineering , vol. 6, no. 1, pp. 86-90, 1998. (hindawi.com)
  • guanine
  • Note that there are three hydrogen bonds between guanine and cytosine, and only two bonds between thymine and adenine. (wikibooks.org)
  • eukaryotic
  • Epigenomic maintenance is a continuous process and plays an important role in stability of eukaryotic genomes by taking part in crucial biological mechanisms like DNA repair. (wikipedia.org)
  • patterns
  • As we've shown, PFGE is Delphinidin chloride normally a good method to anticipate PFGE protocols creates complicated DNA patterns with an increase of than 40 fragments . (scienceofgreathealth.com)
  • The first high quality X-ray diffraction patterns of A-DNA were reported by Rosalind Franklin and Raymond Gosling in 1953. (wikipedia.org)
  • Structural information is generated from X-ray diffraction studies of oriented DNA fibers with the help of molecular models of DNA that are combined with crystallographic and mathematical analysis of the X-ray patterns. (wikipedia.org)
  • That same year, Maurice F. Wilkins, A. Stokes and H.R. Wilson, reported the first X-ray patterns of in vivo B-DNA in partially oriented salmon sperm heads. (wikipedia.org)
  • cell
  • Extensive pedigree analysis at the single‐cell level demonstrated that two consecutive divisions are required to produce one switched cell among four related cousins. (embopress.org)
  • Cell, 120 (2). (cshl.edu)
  • Y. Fujita, Y. Hara, T. Ogino, and C. Suga, "Production of shikonin derivatives by cell suspension cultures of Lithospermum erythrorhizon I. Effects of nitrogen sources on the production of shikonin derivatives," Plant Cell Reports , vol. 1, no. 2, pp. 59-60, 1981. (hindawi.com)
  • We demonstrated the importance of class II and III RNR for proper cell division in biofilm development and maturation. (ibecbarcelona.eu)
  • For this reason, and the fact that much of the research on DNA replication has be carried out on E Coli, we will be looking briefly at cell division in prokaryocytes. (wikibooks.org)
  • The human Diploid cell has 22 matching chromosomes and 2 sex chromosomes (Fig.4). (wikibooks.org)
  • The total length of the DNA in a cell is about 2 meters. (wikibooks.org)
  • The traditional central dogma of biology states that the DNA of a cell is transcribed to RNA, which is translated to proteins, which perform cellular processes and functions. (wikipedia.org)
  • The rate of DNA repair is dependent on many factors, including the cell type, the age of the cell, and the extracellular environment. (wikipedia.org)
  • DNA damage, due to environmental factors and normal metabolic processes inside the cell, occurs at a rate of 10,000 to 1,000,000 molecular lesions per cell per day. (wikipedia.org)
  • The cellular spindle apparatus includes the spindle microtubules, associated proteins, which include kinesin and dynein molecular motors, condensed chromosomes, and any centrosomes or asters that may be present at the spindle poles depending on the cell type. (wikipedia.org)
  • Cell Rep. 18 (2): 432-442. (wikipedia.org)
  • The emerging picture clearly is that RecQ helicases in concert with Top 3 are involved in maintaining genomic stability and integrity by controlling recombination events, and repairing DNA damage in the G2-phase of the cell cycle. (wikipedia.org)
  • allele
  • Reactions also included detrimental template handles to calculate CT beliefs above history as well as HPV-type particular DNA and allele particular primer expansion (ASPE) positive handles to demonstrate general assay achievement. (world-of-links.com)
  • double helix
  • The first reports of a double helix molecular model of B-DNA structure were made by James Watson and Francis Crick in 1953. (wikipedia.org)
  • The twist is the number of helical turns in the DNA and the writhe is the number of times the double helix crosses over on itself (these are the supercoils). (wikipedia.org)
  • Reaction
  • They function through catalyzing the reaction ATP + H2O → ADP + P and thus driving the unwinding of paired DNA and translocating in the 3' to 5' direction. (wikipedia.org)
  • bacterial
  • In 2008, the company supplied some of the DNA stretches used to create a synthetic bacterial genome. (wikipedia.org)
  • vivo
  • Computer molecular models also allow animations and molecular dynamics simulations that are very important for understanding how DNA functions in vivo. (wikipedia.org)
  • Computer molecular modeling allows both animations and molecular dynamics simulations that are very important to understand how DNA functions in vivo. (wikipedia.org)
  • Epigenetic transformation studies of DNA in vivo were however much slower to develop despite their importance for embryology, morphogenesis and cancer research. (wikipedia.org)
  • epigenetic
  • These modifications were termed epigenetic, from epi "on top of" the genetic material "DNA" (Epigenetics 1). (wikipedia.org)
  • triggers
  • Ovulated eggs become arrested in metaphase II until fertilization triggers the second meiotic division. (wikipedia.org)
  • hydrogen
  • In addition, dsDNA (double stranded DNA) in the active site has a wider major groove and shallower minor groove that permits the formation of hydrogen bonds with the third nitrogen of purine bases and the second oxygen of pyrimidine bases. (wikipedia.org)
  • Finally, the active site makes extensive hydrogen bonds with the DNA backbone. (wikipedia.org)
  • The more advanced, computer-based molecular models of DNA involve molecular dynamics simulations and quantum mechanics computations of vibro-rotations, delocalized molecular orbitals (MOs), electric dipole moments, hydrogen-bonding, and so on. (wikipedia.org)
  • consists
  • The etymology of scl-70 consists of an abbreviation of scleroderma and a 70 kD extractable immunoreactive fragment that can be obtained from the otherwise larger (100-105 kD) target topoisomerase antigen (called the SCL-70 Antigen) of the antibodies. (wikipedia.org)