TY - JOUR
T1 - Multiple chromosomal populations of topoisomerase II detected in vivo by time-lapse, three-dimensional wide-field microscopy
AU - Swedlow, Jason R.
AU - Sedat, John W.
AU - Agard, David A.
N1 - Funding Information:
We would especially like to thank Dr. N. Osheroff for helpful discussions concerning the purification of topo II and for supplying samples of Drosophila topo II for activity standards. We are also indebted to H. Chen for writing the data collection (LAMBDA) and analysis (PRISM) software. We thank Dr. hf. Ft. Paddy for the use of BODIPY-histones and images of embryos injected with Cy5-histones. Finally, we thank the members of the Nuclear Structure Cooperative for helpful discussions and T. Hirano, S. Holloway, C. Shamu, A. Dernburg, and K. Kaplan for their thoughtful criticism of this manuscript. This work was supported by the Howard Hughes Medical Institute (J. W. S. and D. A. A.) and by grants from the National Institutes of Health to J. W. S. (GM-25101) and D. A. A. (GM-31627).
PY - 1993/4/9
Y1 - 1993/4/9
N2 - The localization of topoisomerase II (topo II) in vivo was studied by recording time-lapse, three-dimensional data sets of living Drosophila melanogaster embryos injected with rhodamine-labeled topo II. These images show that topo II is concentrated at specific sites within the interphase nucleus and that this localization is temporally regulated. The enzyme is not restricted to a central chromosome axis, but is distributed uniformly throughout the chromosome. During mitosis, the enzyme present in the early prophase chromosome is lost in two stages, following prophase and following anaphase. Overall, 70% of the enzyme leaves the nucleus and diffuses into the cytoplasm. The localization of the enzyme thus correlates with its role in chromosome condensation and segregation. Rather than being solely a structural protein, topo II appears to localize at the sites on the chromosome where it is required.
AB - The localization of topoisomerase II (topo II) in vivo was studied by recording time-lapse, three-dimensional data sets of living Drosophila melanogaster embryos injected with rhodamine-labeled topo II. These images show that topo II is concentrated at specific sites within the interphase nucleus and that this localization is temporally regulated. The enzyme is not restricted to a central chromosome axis, but is distributed uniformly throughout the chromosome. During mitosis, the enzyme present in the early prophase chromosome is lost in two stages, following prophase and following anaphase. Overall, 70% of the enzyme leaves the nucleus and diffuses into the cytoplasm. The localization of the enzyme thus correlates with its role in chromosome condensation and segregation. Rather than being solely a structural protein, topo II appears to localize at the sites on the chromosome where it is required.
UR - http://www.scopus.com/inward/record.url?scp=0027465101&partnerID=8YFLogxK
U2 - 10.1016/0092-8674(93)90163-K
DO - 10.1016/0092-8674(93)90163-K
M3 - Article
C2 - 8384932
AN - SCOPUS:0027465101
SN - 0092-8674
VL - 73
SP - 97
EP - 108
JO - Cell
JF - Cell
IS - 1
ER -