scholarly journals DNA cleavage induced by glycation of Cu, Zn-superoxide dismutase

1994 ◽  
Vol 304 (1) ◽  
pp. 219-225 ◽  
Author(s):  
H Kaneto ◽  
J Fujii ◽  
K Suzuki ◽  
H Kasai ◽  
R Kawamori ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Dna Cleavage ◽  
Fenton Reaction ◽  
Reducing Sugars ◽  
Nuclear Dna ◽  
Dna Fragments ◽  
Radical Scavengers ◽  
Isolated Nuclei ◽  
Hydroxy Radical ◽  
Chelating Reagents

Human Cu,Zn-superoxide dismutase (Cu,Zn-SOD) undergoes site-specific and random fragmentation by non-enzymic glycosylation (glycation). Released Cu2+ from the glycated Cu,Zn-SOD probably facilitates a Fenton reaction to convert H2O2 into hydroxy radical, which then participates in the non-specific fragmentation [Ookawara et al. (1992) J. Biol. Chem. 267, 18505-18510]. In the present study, we investigated the effects of glycated Cu,Zn-SOD on cloned DNA fragments and nuclear DNA and analysed the formation of 8-hydroxydeoxyguanosine (8-OH-dG). Incubation of cloned DNA fragments with Cu,Zn-SOD and reducing sugars resulted in cleavage of the DNA. The extent of the cleavage corresponded to the reducing capacity of the sugar. Metal-chelating reagents, EDTA and bathocuproine, and an H2O2 scavenger, catalase, inhibited the DNA cleavage. Hydroxy radical scavengers and aminoguanidine, an inhibitor of glycation, also inhibited the reaction. Moreover, the glycation of Cu,Zn-SOD caused the substantial formation of 8-OH-dG in DNA. When isolated nuclei were incubated with CuCl2 plus H2O2, nuclear DNA cleavage was observed. Incubation of isolated nuclei with Cu,Zn-SOD that had been pre-incubated with glucose also resulted in nuclear DNA cleavage. These results suggest that hydroxy radical is produced through a Fenton reaction by Cu2+ and H2O2 released from the glycated Cu,Zn-SOD, and participates in nuclear DNA cleavage. This mechanism may partly explain the deterioration of organs under diabetic conditions.

scholarly journals Structural domains of plant nuclear DNA as a constitutive component of the topoisomerase II/DNA complex.

1995 ◽  
Vol 42 (2) ◽  
pp. 201-204 ◽  
Author(s):  
V T Solovyan ◽  
I O Andreyev
Keyword(s):  
Dna Fragmentation ◽  
Dna Cleavage ◽  
Topoisomerase Ii ◽  
Nuclear Dna ◽  
Main Property ◽  
Reverse Reaction ◽  
Dna Fragments ◽  
Structural Domains ◽  
Chromatin Folding ◽  
Dna Complex

The treatment of agarose embedded plant nuclei by strong protein denaturants was demonstrated to result in discrete self-fragmentation of intact nuclear DNA. The set of resultant DNA cleavage products involves two main types of DNA fragments sized about 50-100 kb and 300-500 kb, being of the same type in various eukaryotic representatives. The pattern of ordered DNA fragmentation has been shown to be similar both in intact nuclei and in histone-depleted ones thus suggesting that the observed DNA fragments represent preexisting DNA structural domains, corresponding to the higher levels of chromatin folding. The topoisomerase II-specific poison teniposide (VM-26) has been shown to increase the ordered DNA cleavage while the conditions stimulating the topoisomerase II-mediated reverse reaction lead to the reassociation of the cleaved DNA domains. The data presented suggest that the nuclear DNA structural domains are involved in functioning of the topoisomerase II/DNA complex, the main property of which is its ability to mediate the cleavage/reassociation reactions.

Detection of cell death in human skin wounds of various ages by an in situ end labeling of nuclear DNA fragments

1997 ◽  
Vol 110 (5) ◽  
pp. 240-243 ◽  
Author(s):  
R. Hausmann ◽  
A. Nerlich ◽  
J. T�bel ◽  
P. Betz ◽  
I. Wiest
Keyword(s):  
Cell Death ◽  
Human Skin ◽  
Nuclear Dna ◽  
Skin Wounds ◽  
Dna Fragments

scholarly journals Evidence for production of oxidizing radicals by the particulate O-2- forming system from human neutrophils

Blood ◽  
1979 ◽  
Vol 53 (4) ◽  
pp. 666-676
Author(s):  
AI Tauber ◽  
TG Gabig ◽  
BM Babior
Keyword(s):  
Hydrogen Peroxide ◽  
Superoxide Dismutase ◽  
Ethylene Production ◽  
Human Neutrophils ◽  
Peroxy Acid ◽  
Radical Scavengers ◽  
Alkyl Peroxide ◽  
Acyl Peroxide

The particulate O-2-forming system from human neutrophils was found to oxidize methional and 2-keto-4-methylthiobutyric acid (KMB) to ethylene, indicating the formation by this system of strongly oxidizing radicals. Conforming this interpretation was the observation that ethylene production was inhibited by the radical scavengers benzoate, ethanol, and mannitol. Ethylene production was also sharply reduced by superoxide dismutase, implicatin O-2 as a precursor of oxidizing radicals. In our system catalase only partially inhibited ethylene generation from either methional or KMB, suggesting that oxidizing radicals are generated at least in part by the reacton of O-2 with compounds other than H2O2. We propose that in neutrophils oxidizing radicals are formed in a reaction between O-2 and a peroxide according to the following equation: O-2 + ROOH leads to RO . + OH- + O2, in which ROOH may be hydrogen peroxide, an alkyl peroxide, or an acyl peroxide (i.e., a peroxy acid).

Extra Copper-mediated Enhancement of the DNA Cleavage Activity Supported with Wild-type Cu, Zn Superoxide Dismutase

2008 ◽  
Vol 26 (3) ◽  
pp. 564-570 ◽  
Author(s):  
Ruo-Yu ZHOU ◽  
Wei JIANG ◽  
Li-Na ZHANG ◽  
Li WANG ◽  
Chang-Lin LIU
Keyword(s):  
Superoxide Dismutase ◽  
Dna Cleavage ◽  
Wild Type ◽  
Cleavage Activity ◽  
Dna Cleavage Activity

scholarly journals Molecular analysis of N6-methyladenine patterns in Tetrahymena thermophila nuclear DNA.

1989 ◽  
Vol 9 (6) ◽  
pp. 2598-2605 ◽  
Author(s):  
E E Capowski ◽  
J M Wells ◽  
G S Harrison ◽  
K M Karrer
Keyword(s):  
Molecular Analysis ◽  
Vegetative Growth ◽  
Nuclear Dna ◽  
Tetrahymena Thermophila ◽  
Somatic Growth ◽  
Methylation Pattern ◽  
Molecular Probes ◽  
Dna Fragments ◽  
Methylation Patterns ◽  
Partially Methylated

We have cloned two DNA fragments containing 5'-GATC-3' sites at which the adenine is methylated in the macronucleus of the ciliate Tetrahymena thermophila. Using these cloned fragments as molecular probes, we analyzed the maintenance of methylation patterns at two partially and two uniformly methylated sites. Our results suggest that a semiconservative copying model for maintenance of methylation is not sufficient to account for the methylation patterns we found during somatic growth of Tetrahymena. Although we detected hemimethylated molecules in macronuclear DNA, they were present in both replicating and nonreplicating DNA. In addition, we observed that a complex methylation pattern including partially methylated sites was maintained during vegetative growth. This required the activity of a methylase capable of recognizing and modifying sites specified by something other than hemimethylation. We suggest that a eucaryotic maintenance methylase may be capable of discriminating between potential methylation sites to ensure the inheritance of methylation patterns.

scholarly journals CHROMATIN STRUCTURE AND THE CELL DIVISION CYCLE

1972 ◽  
Vol 55 (2) ◽  
pp. 322-327 ◽  
Author(s):  
Thoru Pederson ◽  
Elliott Robbins
Keyword(s):  
Nuclear Dna ◽  
Binding Capacity ◽  
Nuclear Dna Content ◽  
Living Cells ◽  
S Phase ◽  
Minimal Level ◽  
Binding Profile ◽  
Chromosomal Proteins ◽  
Isolated Nuclei ◽  
Degree Of Association

Measurements of actinomycin-3H binding in synchronized HeLa cells reveal that the binding capacity of chromatin decreases progressively during the S phase despite a doubling of nuclear DNA content, reaches a minimal level during G2 and mitosis, and then increases gradually throughout the subsequent G1 interval. Since this pattern was evident in experiments with living cells, ethanol-fixed cells, and isolated nuclei, but not with purified DNA, the actinomycin binding profile may reflect changes in the degree of association between DNA and chromosomal proteins at different stages of the cell cycle.

The effects of preservatives and temperatures on arachnid DNA

2005 ◽  
Vol 19 (2) ◽  
pp. 99 ◽  
Author(s):  
Cor J. Vink ◽  
Steven M. Thomas ◽  
Pierre Paquin ◽  
Cheryl Y. Hayashi ◽  
Marshal Hedin
Keyword(s):  
Propylene Glycol ◽  
Nuclear Dna ◽  
Pcr Amplification ◽  
The Other ◽  
Dna Fragments ◽  
Cytochrome Oxidase Subunit ◽  
High Quality ◽  
C Storage ◽  
Time Period ◽  
Better Than

We tested the effects of different preservatives and temperatures on the yield of spider and scorpion DNA useable for PCR amplification. Our experiment was designed to simulate conditions in the field and laboratory over a six-week time period, testing the preservatives RNAlater®, propylene glycol, and various ethanol concentrations. Three replicates of each preservation treatment were stored at five different temperature treatments; –80°C, –20°C, 2–4°C, 19–24°C, and 40°C. DNA was extracted and quality was assessed by electrophoresis on mini-gels, and by PCR amplification of high copy mitochondrial DNA fragments (cytochrome oxidase subunit I) and low copy nuclear DNA fragments (actin). Results show that RNAlater® and propylene glycol are significantly better than the other preservatives for high quality DNA preservation and that tissue is best stored at –80°C or –20°C. Storage in 95% ethanol is appropriate if specimens are stored at –20°C or –80°C. We believe our results can help guide biologists in choosing preservatives and temperatures for DNA-based research on arachnids, other arthropods and invertebrates in general.

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