The structure of human S-phase chromosome fibres |
| |
Authors: | Maria Svetlova Ljudmila Solovjeva Grigory Stein Claude Chamberland Baldev Vig Nikolai Tomilin |
| |
Affiliation: | (1) Institute of Cytology, The Russian Academy of Sciences, 194064 St. Petersburg, Russia;(2) Hotel-Dieu Hospital, Laval University Research Centre, G1R 2J6, Quebec, Canada;(3) Department of Biology, University of Nevada, 89557-0015 Reno, NV, USA |
| |
Abstract: | Recentin situ hybridization studies suggested that within the range of 0.1–1.0 Mb, human interphase chromosomes follow a random walk model (i.e. they behave as flexible polymers without major constraints). However, chromosome structure may differ in the G1, S, and G2 phases, and phase-specific constraints may be masked if the chromosome analysis does not discriminate between the phases. Therefore, using confocal microscopy, we examined the structure of S-phase chromosomes labelled with 5-iododeoxyuridine after prolonged treatment with 5-fluorodeoxyuridine. In the S-phase, labelled 0.32 µ chromosome fibres mostly appear as semi-circles with an average diameter of 0.83 ±0.03 µ. These semi-circles are joined together to form different 3D structures, and two semicircles frequently adopt s- or-like conformations involving about 2.5 µ of the chromosome contour length (L). Morphometric analysis of the S-phase fibres suggests that our data fit both the random flexible polymer model and also a model in which two constrained semi-circles are attached to each other by a flexible joint, thus eliminating constraints at long distances (L more than 2 µ). |
| |
Keywords: | chromosome confocal microscopy conformation FISH human chromosomes replicative label |
本文献已被 SpringerLink 等数据库收录! |
|