Observations on chromosome duplication in cultured human leucocytes

Bader, Saul; Miller, Orlando J.; Mukherjee, Barid B.

doi:10.1016/0014-4827(63)90159-9

Cited by 43 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, the metasynchronous theory of replication of the DNA of homologous chromosomes postulates a time differential between homologous DNA, this time differential varying from locus to locus, from chromosome to chromosome and from time to time in the S period. The conflicting data in the literature may be related, then, to varying times of exposure of the cells to labeled compounds, i.e.y 3H-thymidine, very short exposure leading to spurious evidence for antisynchrony, long exposure to synchrony (German, 1962(German, ,1964aBader et a!., 1963;BianchiandDe Bianchi, 1965;Stubblefield, 1965;Gilbert et al, 1966;M arshall Graves, 1967).…”

Section: Discussionmentioning

confidence: 99%

Chronology and pattern of human chromosome replication

Aa¹,

Takagi²,

Ml³

et al. 1968

Cytogenet Genome Res

View full text Add to dashboard Cite

The chronology of DNA synthesis in homologous chromosomes was investigated autoradiographically and statistically. The statistical approach addressed itself toward establishing rigorously the occurrence of synchrony or antisynchrony in the autosomal pairs of groups A and E. In order to evaluate DNA synthesis more intimately, chromosome No. 2, whose short and long arms can be readily identified morphologically, was divided into five arbitrarily defined segments, and the autoradiographic behavior of these was determined. Neither consistent synchrony nor antisynchrony was found to characterize the group A homologs and the segments of No. 2. In contrast to the above findings, chromosomal pair 16 apparently replicated much of its DNA antisynchronously, and a suggestion of similar behavior was obtained for pairs 17 and 18. Nevertheless, exceptions for certain chromosomes at certain times in the S period were found, indicating synchrony or antisynchrony to be present under the conditions of the experiments. Even though no one simple and universal explanation appears to be compatible with the complex data presented, the results are compatible with metasynchronous replication of DNA in homologous chromosomes. This method of replication postulates a time gap of varying length between two homologous DNA loci on chromosomes, this time gap varying from locus to locus, from chromosome to chromosome and from time to time in the S period. Thus, the time length of exposure of cells to labeled thymidine plays a crucial and all-important factor in the type of data obtained autoradiographically and accounts for the diverse statements made in the literature regarding homolog replication.

show abstract

Section: Discussionmentioning

confidence: 99%

Chronology and pattern of human chromosome replication

Aa¹,

Takagi²,

Ml³

et al. 1968

Cytogenet Genome Res

View full text Add to dashboard Cite

show abstract

“…Many studies have indicated that the DNA of mammalian cells is replicated in a specific temporal order (Bader et al, 1963;Braun and Wili 1969;Burke and Fangman, 1975;Kikuchi and Sandberg, 1964;Mueller and Kajiwara, 1966;Mukherjee et al, 1968;Taylor, 1960;Taylor et al, 1971). Furthermore, the period in S phase during which an individual gene is replicated appears to be identical and heritable from one cell generation to the next (Aebersold and Burki, 1976;Amaldi et al, 1969;Balazs et al, 1973;Giacomoni and Finkel, 1972;Hamper et al, 1974;Kasupski and Mukherjee, 1977;Kee and Haber, 1975;Orkin and Littlefield, 1971;Stambrook, 1974;Taylor, 1974).…”

mentioning

confidence: 99%

Dependence of lethality induced by a direct DNA perturbation of synchronized human diploid fibroblasts on different periods of the DNA synthetic period (S Phase)

Tsutsui

Ohmori

Suzuki

et al. 1984

Journal Cellular Physiology

View full text Add to dashboard Cite

The cytotoxic effect of a direct perturbation of DNA during various portions of the DNA synthetic period (S phase) of cultured human diploid fibroblasts was examined. The cells were synchronized by a period of growth in low serum with a subsequent blockage of the cells at the G1/S boundary by hydroxyurea. This method resulted in over 90% synchrony, although approximately 20% of the cells were noncycling. Synchronized cells were treated for each of four 2-hour periods during the S phase with 5-bromodeoxyuridine (0.1-10 microM), followed by irradiation with near-UV (5-10 min). The 5-bromodeoxyuridine-plus-irradiation treatment was cytotoxic, while treatment with 5-bromodeoxyuridine alone or irradiation alone was not cytotoxic. The cytotoxicity was dependent upon the periods of S phase during which treatment was administered. The highest lethality was observed for treatment in early to middle S phase, particularly in the first 2 hours of S phase, whereas scarce lethality was observed in late S phase. The extent of substitution of 5-bromodeoxyuridine for thymidine in newly synthesized DNA was similar in every period of the S phase. Furthermore, no specific period during S phase was significantly more sensitive to treatment with respect to DNA damage, as determined by an induction of unscheduled DNA synthesis. These results suggest that a certain region or regions in the DNA of human diploid fibroblasts, as designated by their specific temporal relationship in the S phase, may be more sensitive to the DNA perturbation by 5-bromodeoxyuridine treatment plus near-UV irradiation for cell survival.

show abstract

“…Following the definition of the XO sex chromosomal abnormality in many pa¬ tients with the features of Turner's syn¬ drome by Ford et (F) Al [1][2][3][4][5][6][7][8][9][10][11][12] (F) (M) (F) Bl …”

mentioning

confidence: 99%