Title: | DNA combing reveals intrinsic temporal disorder in the replication of yeast chromosome VI |
Author(s): | Czajkowsky DM; Liu J; Hamlin JL; Shao Z; |
Address: | "Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA" |
DOI: | 10.1016/j.jmb.2007.10.046 |
ISSN/ISBN: | 1089-8638 (Electronic) 0022-2836 (Print) 0022-2836 (Linking) |
Abstract: | "It is generally believed that DNA replication in most eukaryotes proceeds according to a precise program in which there is a defined temporal order by which each chromosomal region is duplicated. However, the regularity of this program at the level of individual chromosomes, in terms of both the relative timing and the size of the DNA domain, has not been addressed. Here, the replication of chromosome VI from synchronized budding yeast was studied at a resolution of approximately 1 kb with DNA combing and fluorescence microscopy. Contrary to what would be expected from cells following a rigorous temporal program, no two molecules exhibited the same replication pattern. Moreover, a direct evaluation of the extent to which the replication of distant chromosomal segments was coordinated indicates that the overwhelming majority of these segments were replicated independently. Importantly, averaging the patterns of all the fibers examined recapitulates the ensemble-averaged patterns obtained from population studies of the replication of chromosome VI. Thus, rather than an absolutely defined temporal order of replication, replication timing appears to be essentially probabilistic within individual cells, exhibiting only temporal tendencies within extended domains" |
Keywords: | "Bromodeoxyuridine/metabolism *Chromosomes, Fungal DNA Replication/*physiology DNA, Fungal/*analysis/chemistry/*genetics G1 Phase/drug effects Gene Dosage Genes, Fungal Mating Factor Peptides/metabolism/pharmacology Promoter Regions, Genetic S Phase Saccha;" |
Notes: | "MedlineCzajkowsky, Daniel M Liu, Jie Hamlin, Joyce L Shao, Zhifeng eng R01 GM068729/GM/NIGMS NIH HHS/ R21 HG003702-01/HG/NHGRI NIH HHS/ HG003702/HG/NHGRI NIH HHS/ R01 GM068729-02/GM/NIGMS NIH HHS/ R01 GM068729-01A1/GM/NIGMS NIH HHS/ R01 GM068729-03/GM/NIGMS NIH HHS/ R21 HG003702/HG/NHGRI NIH HHS/ GM026108/GM/NIGMS NIH HHS/ GM068729/GM/NIGMS NIH HHS/ R01 GM026108-28/GM/NIGMS NIH HHS/ R01 GM026108/GM/NIGMS NIH HHS/ R21 HG003702-02/HG/NHGRI NIH HHS/ Research Support, N.I.H., Extramural Review Netherlands 2007/11/15 J Mol Biol. 2008 Jan 4; 375(1):12-9. doi: 10.1016/j.jmb.2007.10.046. Epub 2007 Oct 23" |