caa a22 4500 477089178 CHVBK 20180405111511.0 cr unu---uuuuu 170330e19960101xx s 000 0 eng 10.1007/BF02254938 doi (NATIONALLICENCE)springer-10.1007/BF02254938 Sumner A. MRC Human Genetics Unit, Western General Hospital, Crewe Road, EH4 2XU, Edinburgh, UK aut The distribution of topoisomerase II on mammalian chromosomes [Elektronische Daten] [A. Sumner] The distribution of topoisomerase II (Topo II) has been studied using immunofluorescence on cytocentrifuged preparations of mammalian chromosomes. Immunolabelling of Topo II is affected by choice of fixative, by barriers to accessibility and by the lability of the enzyme. Chromosomes still embedded in cytoplasm remain unlabelled, while in contrast Topo II can easily be lost from some sites in chromosomes free of cytoplasm. The definitive distribution of Topo II consists of a line along the centre of each chromatid, corresponding to the chromosome core or scaffold, and quantities of Topo II elsewhere in the chromosomes which vary during the course of mitosis. A strong reaction for Topo II can be seen throughout prophase chromosomes, consistent with a role in condensation and/or segregation of the chromosome arms at this stage. At metaphase, Topo II is restricted to the centromeric regions, the only parts of the chromosomes that still have to be separated at this stage, while in anaphase, after segregation has occurred, this centromeric concentration of Topo II is lost. The distribution and quantity of Topo II in mammalian chromosomes is thus wholly consistent with the known functions of this enzyme in chromosome condensation and segregation. Rapid Science Publishers, 1996 chromosomes nationallicence mitosis nationallicence topoisomerase II nationallicence Chromosome Research Kluwer Academic Publishers 4/1(1996-01-01), 5-14 0967-3849 4:1<5 1996 4 10577 https://doi.org/10.1007/BF02254938 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02254938 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Sumner A. MRC Human Genetics Unit, Western General Hospital, Crewe Road, EH4 2XU, Edinburgh, UK aut NATIONALLICENCE 773 0- Chromosome Research Kluwer Academic Publishers 4/1(1996-01-01), 5-14 0967-3849 4:1<5 1996 4 10577 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer