Abstract
ENDO-REDUPLICATION as defined by Levan and Hauschka1 consists of a microscopically non-visible duplication of the chromosomes within the cell nucleus leading to the formation of so-called ‘diplochromosomes’ in the following mitosis. Endo-reduplication, has been reported to occur regularly, although rarely, in human tissues in vitro2,3. In a previous paper3, we showed that in cultured human fibroblasts diplochromosomes originate by two separate and successive chromosome duplications. Diplochromosomes of endo-reduplicated cells which took up tritiated thymidine during the second chromosome replication show all four chromatids labelled in the following metaphase, whereas when tritiated thymidine was given during the first chromosome replication the label was restricted to but one chromatid of each of the two chromosomes forming a diplochromosome. These observations lead to the conclusion that the chromatids of diplochromosomes are, like chromatids of ordinary human chromosomes4, composed of two sub-units which are distributed in a semi-conservative mode during chromosome duplications. The duration of one endo-reduplication cycle is in the range of two cycles of a diploid cell.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Levan, A., and Hauschka, T. S., J. Nat. Cancer Inst., 14, 1 (1953).
Fraccaro, M., Kaijser, K., and Lindsten, J., Ann. Hum. Genet., 24, 45 (1960).
Schwarzacher, H. G., and Schnedl, W., Cytogenetics, 4, 1 (1965).
Prescott, D. M., and Bender, M., Exp. Cell. Res., 29, 430 (1963).
Jackson, J. F., Exp. Cell. Res., 31, 194 (1963).
Moorhead, P. S., Nowell, P. C., Mellman, J. W., Batipps, D. M., and Hungerford, D. A., Exp. Cell Res., 20, 613 (1960).
Bloch, D., Proc. U.S. Nat. Acad. Sci., 41, 1058 (1955).
Taylor, J. H., in Molecular Genetics, 1, 65 (1963).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
SCHWARZACHER, H., SCHNEDL, W. Position of Labelled Chromatids in Diplochromosomes of Endo-reduplicated Cells after Uptake of Tritiated Thymidine. Nature 209, 107–108 (1966). https://doi.org/10.1038/209107a0
Issue Date:
DOI: https://doi.org/10.1038/209107a0
This article is cited by
-
Unbiased segregation of fission yeast chromosome 2 strands to daughter cells
Chromosome Research (2013)
-
The diplochromosome of endoreduplicated cells: A new approach to highlight the mechanism of sister chromatid exchange
Chromosoma (1996)
-
Chemical induction of quadruple and octuple chromosomes in Chinese hamster CHO-K1 cells and relationship between their three-dimensional structure and spatial distribution of BrdU-labeled chromatids
Chromosoma (1994)
-
Significance of polyploidy in megakaryocytes and other cells in health and tumor disease
Klinische Wochenschrift (1987)
-
Induction of endoreduplication by hydrazine in Chinese hamster V 79 cells and reduced incidence of sister chromatid exchanges in endoreduplicated mitoses
Chromosoma (1984)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.