Nuclear distribution of Drosophila DNA topoisomerase II is sensitive to both RNase and DNase

1995 ◽  
Vol 108 (4) ◽  
pp. 1651-1657 ◽  
Author(s):  
V.H. Meller ◽  
P.A. Fisher
Keyword(s):  
Topoisomerase Ii ◽  
Immunoblot Analysis ◽  
Dnase I ◽  
Rnase A ◽  
Drosophila Embryo ◽  
Micrococcal Nuclease ◽  
Cell Fractionation ◽  
Dna Topoisomerase Ii ◽  
Dna Topoisomerase ◽  
Nuclear Distribution

The nuclear distribution of Drosophila DNA topoisomerase II was determined by immunoblot analysis after nuclease digestion and cell fractionation. About 60% of DNA topoisomerase II could be removed from nuclei by RNase A, about 70% by DNase I, and about 90% by incubation with both enzymes together or with micrococcal nuclease. Nuclease treatment of nuclei did not affect the distribution of lamins Dm1 and Dm2 or other nuclear proteins similarly. Nuclease-mediated solubilization of DNA topoisomerase II from Drosophila nuclei was also dependent on NaCl concentration. Solubilization was not efficient below 100 mM NaCl. Sucrose velocity gradient ultracentrifugation demonstrated that DNA topoisomerase II solubilized from nuclei by either RNase A or DNase I migrated at about 9 S, as expected for the homodimer. Results of chemical crosslinking supported this observation. We conclude that DNA topoisomerase II has both RNA- and DNA-dependent anchorages in Drosophila embryo nuclei.

scholarly journals An RNase-sensitive particle containing Drosophila melanogaster DNA topoisomerase II.

1994 ◽  
Vol 126 (6) ◽  
pp. 1331-1340 ◽  
Author(s):  
V H Meller ◽  
M McConnell ◽  
P A Fisher
Keyword(s):  
Rna Polymerase Ii ◽  
Topoisomerase Ii ◽  
Sedimentation Coefficient ◽  
Rnase A ◽  
Micrococcal Nuclease ◽  
Nuclear Antigen ◽  
Nuclear Pore ◽  
Dna Topoisomerase Ii ◽  
Dna Topoisomerase ◽  
Topo Ii

Most DNA topoisomerase II (topo II) in cell-free extracts of 0-2-h old Drosophila embryos appears to be nonnuclear and remains in the supernatant after low-speed centrifugation (10,000 g). Virtually all of this apparently soluble topo II is particulate with a sedimentation coefficient of 67 S. Similar topo II-containing particles were detected in Drosophila Kc tissue culture cells, 16-19-h old embryos and extracts of progesterone-matured oocytes from Xenopus. Drosophila topo II-containing particles were insensitive to EDTA, Triton X-100 and DNase I, but could be disrupted by incubation with 0.3 M NaCl or RNase A. After either disruptive treatment, topo II sedimented at 9 S. topo II-containing particles were also sensitive to micrococcal nuclease. Results of chemical cross-linking corroborated those obtained by centrifugation. Immunoblot analyses demonstrated that topo II-containing particles lacked significant amounts of lamin, nuclear pore complex protein gp210, proliferating cell nuclear antigen, RNA polymerase II subunits, histones, coilin, and nucleolin. Northern blot analyses demonstrated that topo II-containing particles lacked U RNA. Thus, current data support the notion that nonnuclear Drosophila topo II-containing particles are composed largely of topo II and an unknown RNA molecule(s).

The in vivo distribution and dynamics of DNA topoisomerase II in Drosophila embryonic nuclei and chromosomes

1993 ◽  
Vol 51 ◽  
pp. 74-75
Author(s):  
Jason R. Swedlow ◽  
Neil Osheroff ◽  
Tim Karr ◽  
John W. Sedat ◽  
David A. Agard
Keyword(s):  
Topoisomerase Ii ◽  
Biochemical Characterization ◽  
Developmental Cycle ◽  
Dna Topoisomerase Ii ◽  
Chromosomal Distribution ◽  
Dna Topoisomerase ◽  
Ideal System ◽  
Dnase Treatment

DNA topoisomerase II is an ATP-dependent double-stranded DNA strand-passing enzyme that is necessary for full condensation of chromosomes and for complete segregation of sister chromatids at mitosis in vivo and in vitro. Biochemical characterization of chromosomes or nuclei after extraction with high-salt or detergents and DNAse treatment showed that topoisomerase II was a major component of this remnant, termed the chromosome scaffold. The scaffold has been hypothesized to be the structural backbone of the chromosome, so the localization of topoisomerase II to die scaffold suggested that the enzyme might play a structural role in the chromosome. However, topoisomerase II has not been studied in nuclei or chromosomes in vivo. We have monitored the chromosomal distribution of topoisomerase II in vivo during mitosis in the Drosophila embryo. This embryo forms a multi-nucleated syncytial blastoderm early in its developmental cycle. During this time, the embryonic nuclei synchronously progress through 13 mitotic cycles, so this is an ideal system to follow nuclear and chromosomal dynamics.

DNA Topoisomerase II Enzymes as Molecular Targets for Cancer Chemotherapy

2010 ◽  
Vol 999 (999) ◽  
pp. 1-14 ◽  
Author(s):  
K. Chikamori ◽  
A.G. Grozav ◽  
T. Kozuki ◽  
D. Grabowski ◽  
R. Ganapathi ◽  
...  
Keyword(s):  
Cancer Chemotherapy ◽  
Topoisomerase Ii ◽  
Molecular Targets ◽  
Dna Topoisomerase Ii ◽  
Dna Topoisomerase

scholarly journals Molecular cloning of partial cDNAs for rat DNA topoisomerase II isoforms and their differential expression in brain development.

1993 ◽  
Vol 268 (25) ◽  
pp. 19076-19083
Author(s):  
K. Tsutsui ◽  
K. Tsutsui ◽  
S. Okada ◽  
M. Watanabe ◽  
T. Shohmori ◽  
...  
Keyword(s):  
Brain Development ◽  
Molecular Cloning ◽  
Differential Expression ◽  
Topoisomerase Ii ◽  
Dna Topoisomerase Ii ◽  
Dna Topoisomerase

scholarly journals Multiple forms and cellular localization of Drosophila DNA topoisomerase II.

1986 ◽  
Vol 261 (17) ◽  
pp. 8063-8069
Author(s):  
R A Heller ◽  
E R Shelton ◽  
V Dietrich ◽  
S C Elgin ◽  
D L Brutlag
Keyword(s):  
Cellular Localization ◽  
Topoisomerase Ii ◽  
Dna Topoisomerase Ii ◽  
Multiple Forms ◽  
Dna Topoisomerase

scholarly journals Proteasomal inhibition potentiates drugs targeting DNA topoisomerase II

2016 ◽  
Vol 103 ◽  
pp. 29-39 ◽  
Author(s):  
Ka C. Lee ◽  
Rebecca L. Bramley ◽  
Ian G. Cowell ◽  
Graham H. Jackson ◽  
Caroline A. Austin
Keyword(s):  
Topoisomerase Ii ◽  
Dna Topoisomerase Ii ◽  
Dna Topoisomerase ◽  
Proteasomal Inhibition

4-Methyl-7-(tetradecanoyl)-2H-1-benzopyran-2-one: a novel DNA topoisomerase II inhibitor with adulticidal and embryostatic activity against sub-periodic Brugia malayi

2004 ◽  
Vol 92 (3) ◽  
pp. 177-182 ◽  
Author(s):  
Shailja Misra-Bhattacharya ◽  
Diksha Katiyar ◽  
Preeti Bajpai ◽  
R.P. Tripathi ◽  
J.K. Saxena
Keyword(s):  
Topoisomerase Ii ◽  
Brugia Malayi ◽  
Dna Topoisomerase Ii ◽  
Dna Topoisomerase ◽  
Topoisomerase Ii Inhibitor
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