Molecular profile of the D. melanogaster mutant genotype w1118 in the presence of variable amount of deuterium (D)

Mapping Intimacies ◽

10.53040/gppb7.2021.31 ◽

2021 ◽

Author(s):

Gallia Butnaru ◽

◽

Sorina Popescu ◽

Keyword(s):

Drosophila Melanogaster ◽

Dna Synthesis ◽

Nuclear Dna ◽

Culture Media ◽

Mutant Line ◽

Molecular Profile ◽

Variable Amount ◽

Mutant Genotype ◽

Very High

The Drosophila melanogaster w1118 mutant line was used to identify the effect of deuterium (D) on DNA synthesis. D concentrations ranged from 30ppm to 96.89% (low and very high amount respec-tively). Five generations of flies were bred on culture media prepared with 6 concentrations of D. For each generation the DNA was analyzed, and its variability was established. The results showed a small involvement of D in the successive synthesis of nuclear DNA.

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Continuous DNA replication in the nucleus of the dinoflagellate Prorocentrum micans (Ehrenberg)

Journal of Cell Science ◽

10.1242/jcs.27.1.81 ◽

1977 ◽

Vol 27 (1) ◽

pp. 81-90

Author(s):

S.A. Filfilan ◽

D.C. Sigee

Keyword(s):

Electron Microscope ◽

Dna Synthesis ◽

Nuclear Dna ◽

Continuous Process ◽

Prorocentrum Micans ◽

Interphase Nuclei ◽

Electron Microscope Autoradiography ◽

Dividing Cells ◽

High Degree ◽

Very High

The uptake of tritiated thymine into cells of a heterogeneous population of Prorocentrum micans was investigated using light-microscope and electron-microscope autoradiography. Specificity of thymine uptake into DNA was demonstrated by the specific removal of label from wax-embedded material using DNase and by the high degree of localization of nuclear label to chromosomes in the electron-microscope autoradiographs. All nuclei, including both dividing and non-dividing cells, showed a substantial uptake of label, indicating that nuclear DNA synthesis in Prorocentrum micans is a continuous process. The level of DNA synthesis does show considerable variation, however, with very high levels in some interphase nuclei. The continuous replication of nuclear DNA provides further evidence of dinoflagellate affinity to the prokaryotes, and indicates that Prorocentrum micans is a very primitive eukaryote cell.

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MUTAGENESIS IN OOCYTES OF DROSOPHILA MELANOGASTER. I. SCHEDULED SYNTHESIS OF NUCLEAR AND MITOCHONDRIAL DNA AND UNSCHEDULED DNA SYNTHESIS

Genetics ◽

10.1093/genetics/104.2.279 ◽

1983 ◽

Vol 104 (2) ◽

pp. 279-299

Author(s):

Mark R Kelley ◽

William R Lee

Keyword(s):

Dna Repair ◽

Mitochondrial Dna ◽

Drosophila Melanogaster ◽

Dna Synthesis ◽

Nuclear Dna ◽

Germ Line ◽

Mutation Induction ◽

Time Interval ◽

Unscheduled Dna Synthesis ◽

Female Germ Line

ABSTRACT As a model system for studying mutagenesis, the oocyte of Drosophila melanogaster has exhibited considerable complexity. Very few experiments have been conducted on the effect of exposing oocytes to chemical mutagens, presumably due to their lower mutational response relative to sperm and spermatids. This lower response may be due either to a change in probability of mutation induction per adduct due to a change in the type of DNA repair or to a lower dose of the mutagen to the female germ line. To study molecular dosimetry and DNA repair in the oocyte, the large number of intracellular constituents (mtDNA, RNA, nucleic acid precursors and large quantities of proteins and lipids) must be separated from nuclear DNA. In this paper we present results showing reliable separation of such molecules enabling us to detect scheduled nuclear and mitochondrial DNA synthesis. We also, by understanding the precise timing of such events, can detect unscheduled DNA synthesis (UDS) as a measure of DNA repair. Furthermore, by comparing the UDS results in a repair competent (Ore-R) vs. a repair deficient (mei-9L1) strain, we have shown the oocyte capable of DNA repair after treatment with ethyl methanesulfonate (EMS). We conclude that the important determinant of mutation induction in oocytes after treatment with EMS is the time interval between DNA alkylation and DNA synthesis after fertilization, i.e., the interruption of continuous DNA repair.

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CHROMOSOMAL DNA SYNTHESIS IN DROSOPHILA MELANOGASTER

The Journal of Cell Biology ◽

10.1083/jcb.39.2.415 ◽

1968 ◽

Vol 39 (2) ◽

pp. 415-429 ◽

Cited By ~ 29

Author(s):

E. F. Howard ◽

W. Plaut

Keyword(s):

Drosophila Melanogaster ◽

Dna Synthesis ◽

Chromosome Region ◽

Chromosomal Dna ◽

Ordered Arrays ◽

Intermediate Time ◽

High Degree ◽

Chromosome Segments ◽

Very High ◽

Chromosome Regions

Analysis of labeling patterns in three chromosome segments of Drosophila melanogaster has shown that the replicative activity within chromosomes is temporally ordered. Moreover, specific labeling patterns on one chromosome occur with specific patterns on another chromosome with a very high degree of correlation. This circumstance leads to the conclusion that DNA synthesis among all the regions in the three chromosome segments studied is coordinated. The various labeling patterns observed in any one chromosome and the combinations of labeling patterns observed in all three chromosome segments can be arranged in ordered arrays, if one assumes that the DNA synthesis in each chromosome region will go to completion without stopping once it has started. Such arrays can serve as models for the temporal order of DNA synthesis among chromosome regions. They predict that in any one chromosome DNA replication begins and ends at very few loci and that synthesis at a larger number of points occurs at an intermediate time.

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Multi-Locus Selection and the Structure of Variation at the white Gene of Drosophila melanogaster

Genetics ◽

10.1093/genetics/144.2.635 ◽

1996 ◽

Vol 144 (2) ◽

pp. 635-645 ◽

Cited By ~ 3

Author(s):

David A Kirby ◽

Wolfgang Stephan

Keyword(s):

Drosophila Melanogaster ◽

White Gene ◽

Transcriptional Unit ◽

North American Population ◽

Evolutionary Mechanisms ◽

Locus Selection ◽

Neutral Equilibrium ◽

History Of ◽

High Degree ◽

Very High

Abstract We surveyed sequence variation and divergence for the entire 5972-bp transcriptional unit of the white gene in 15 lines of Drosophila melanogaster and one line of D. simulans. We found a very high degree of haplotypic structuring for the polymorphisms in the 3′ half of the gene, as opposed to the polymorphisms in the 5′ half. To determine the evolutionary mechanisms responsible for this pattern, we sequenced a 1612-bp segment of the white gene from an additional 33 lines of D. melanogaster from a European and a North American population. This 1612-bp segment encompasses an 834bp region of the white gene in which the polymorphisms form high frequency haplotypes that cannot be explained by a neutral equilibrium model of molecular evolution. The small number of recombinants in the 834bp region suggests epistatic selection as the cause of the haplotypic structuring, while an investigation of nucleotide diversity supports a directional selection hypothesis. A multi-locus selection model that combines features from both-hypotheses and takes the recent history of D. melanogaster into account may be the best explanation for these data.

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Involvement of deoxyribonucleic acid polymerase β in nuclear deoxyribonucleic acid synthesis

Biochemical Journal ◽

10.1042/bj1730309 ◽

1978 ◽

Vol 173 (1) ◽

pp. 309-314 ◽

Cited By ~ 12

Author(s):

T R Butt ◽

W M Wood ◽

E L McKay ◽

R L P Adams

Keyword(s):

Dna Synthesis ◽

Dna Polymerase ◽

Deoxyribonucleic Acid ◽

Nuclear Dna ◽

Dna Polymerase Beta ◽

Cell Nuclei ◽

High Molecular Weight Dna ◽

Dna Polymerase Alpha ◽

Polymerase Beta

The effects on DNA synthesis in vitro in mouse L929-cell nuclei of differential extraction of DNA polymerases alpha and beta were studied. Removal of all measurable DNA polymerase alpha and 20% of DNA polymerase beta leads to a 40% fall in the replicative DNA synthesis. Removal of 70% of DNA polymerase beta inhibits replicative synthesis by 80%. In all cases the nuclear DNA synthesis is sensitive to N-ethylmaleimide and aCTP (arabinosylcytosine triphosphate), though less so than DNA polymerase alpha. Addition of deoxyribonuclease I to the nuclear incubation leads to synthesis of high-molecular-weight DNA in a repair reaction. This occurs equally in nuclei from non-growing or S-phase cells. The former nuclei lack DNA polymerase alpha and the reaction reflects the sensitivity of DNA polymerase beta to inhibiton by N-ethylmaleimide and aCTP.

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Stimulation of Nuclear DNA Synthesis in Perfused Rat Liver by a Specific Hepatopoietic Factor

Hormone and Metabolic Research ◽

10.1055/s-2007-1019342 ◽

1981 ◽

Vol 13 (10) ◽

pp. 584-585 ◽

Cited By ~ 1

Author(s):

S. Silz ◽

G. Ruhenstroth-Bauer

Keyword(s):

Dna Synthesis ◽

Rat Liver ◽

Nuclear Dna ◽

Perfused Rat Liver ◽

Stimulation Of

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CYTOPLASMIC DNA SYNTHESIS IN AMOEBA PROTEUS

The Journal of Cell Biology ◽

10.1083/jcb.15.3.525 ◽

1962 ◽

Vol 15 (3) ◽

pp. 525-534 ◽

Cited By ~ 39

Author(s):

M. Rabinovitch ◽

W. Plaut

Keyword(s):

Dna Synthesis ◽

Tritiated Thymidine ◽

Amoeba Proteus ◽

Living Cells ◽

Large Numbers ◽

Cytoplasmic Dna ◽

Basic Dyes ◽

Nuclease Digestion ◽

High Degree ◽

Very High

The incorporation of tritiated thymidine in Amoeba proteus was reinvestigated in order to see if it could be associated with microscopically detectable structures. Staining experiments with basic dyes, including the fluorochrome acridine orange, revealed the presence of large numbers of 0.3 to 0.5 µ particles in the cytoplasm of all cells studied. The effect of nuclease digestion on the dye affinity of the particles suggests that they contain DNA as well as RNA. Centrifugation of living cells at 10,000 g leads to the sedimentation of the particles in the centrifugal third of the ameba near the nucleus. Analysis of centrifuged cells which had been incubated with H3-thymidine showed a very high degree of correlation between the location of the nucleic acid-containing granules and that of acid-insoluble, deoxyribonuclease-sensitive labeled molecules and leads to the conclusion that cytoplasmic DNA synthesis in Amoeba proteus occurs in association with these particles.

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Meiotic DNA synthesis during mouse spermatogenesis.

The Journal of Cell Biology ◽

10.1083/jcb.64.1.211 ◽

1975 ◽

Vol 64 (1) ◽

pp. 211-222 ◽

Cited By ~ 37

Author(s):

M L Meistrich ◽

B O Reid ◽

W J Barcellona

Keyword(s):

Dna Synthesis ◽

Nuclear Dna ◽

Sodium Dodecyl ◽

Phenol Extraction ◽

Sperm Dna ◽

Sperm Nuclei ◽

Cauda Epididymidis ◽

Contamination Levels ◽

Triton X ◽

Mechanical Shearing

The incorporation of radioactivity into various cells in the sequence of spermatogenesis was measured by preparing highly purified spermatozoan nuclei from the cauda epididymidis of mice at daily intervals after injection of (3H)thymidine. The stages of differentiation of these sperm at the time of thymidine administration were calculated from the kinetics of spermatogenesis. The procedure for purification of sperm nuclei included sonication, mechanical shearing, and treatment with trypsin, DNase, Triton X-100, 2M NaC1, and sodium dodecyl sulfate. DNA was isolated from these nuclei by treatment with dithiothreitol and pronase, followed by phenol extraction and ethanol precipitation. The levels of radioactivity in the epididymal sperm head preparations were low (less than 13 dpm/mouse) for 27 days after injection, and then rose dramatically to over 4 times 104 dpm/mouse. Further experiments demonstrated that the 11 dpm of 3H radioactivity contained in sperm heads at 21 or 26 days after injection of (3H)TdR was significantly above background and contamination levels from other cells or other sources. Most of the radioactivity was in the sperm DNA and represented incorporation of tritium from (3H)TdR into the nuclear DNA of meiotic cells at 0.002 percent of the rate of incorporation into S-phase cells. Little, if any, (3H)TdR was incorporation into the DNA of spermatids. The levels of DNA synthesis during the meiotic prophase in the mouse appear to be much lower than those reported for other organisms.

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