Abstract
The degree of synchrony in the course of the interphase periods G1, S and G2 and in the initiation of mitosis in the several nuclei of each cell of a polynucleate population induced by treatment with 0.1% caffeine, in root meristems of Allium cepa, through inhibition of cytokinesis in two successive cell divisions is analysed by means of labelling with 3H-thymidine.—The S period is initiated simultaneously in all the nuclei of each polynucleate cell, which supports the hypothesis of a factor present in the cytoplasm that is responsible for inducing DNA synthesis.—However, all the nuclei in a polynucleate cell do not pass from the S period to the G2 period simultaneously, those surrounded by the greatest amount of cytoplasm, generally the outer nuclei, being the first to complete the S period (“early nuclei”) and beginning the prophase before their fellow-nuclei in the same cell (“late nuclei”).—From the metaphase onwards, however, all the nuclei in a polynucleate cell continue to develop synchronously. The synchronizing mechanism has a twofold aspect: the shortening of the G2 period in the “late nuclei” and the lengthening of it in the “early ones” and, on the other hand, an arrest of prophase in the “early nuclei” until the “late ones” have caught up, which suggests the existence of an inhibiting factor produced by the “late nuclei” capable of acting upon the early ones through the cytoplasm.
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References
Baserga, R.: Biochemistry of the cell cycle:a review. Cell Tiss. Kinet. 1, 167–191 (1968).
Braun, R., Mittermayer, C., Rusch, H. P.: Sequential temporal replication of DNA in Physarum polycephalum. Proc. nat. Acad. Sci. (Wash.) 53, 924–931. (1965).
De Terra, N.: A study of nucleo-cytoplasmic interactions during cell division in Stentor coeruleus. Exp. Cell. Res. 21, 41–48 (1960).
—: Macronucleolar DNA synthesis in Stentor: regulation by a cytoplasmic initiator. Proc. nat. Acad. Sci. (Wash.) 57, 607–614 (1967).
Fernández-Gómez, M. E.: Rate of DNA synthesis in binucleate cells. Histochemie 12, 302–306 (1968).
Giménez-Martín, G., González-Fernández, A., López-Sáez, J. F.: A new method of labeling cells. J. Cell Biol. 26, 305–309 (1965a).
—, López-Sáez, J. F., Moreno, P., González-Fernández, A.: On the triggering of mitosis and the division cycle of polynucleate cells. Chromosoma (Berl.) 25, 282–296 (1968).
—, Risueno, M. C., López-Sáez, J. F.: Nuclear fusion in somatic cells. Observations with the electron microscope. Fiton 22, 173–175 (1965b).
González-Fernández, A., Giménez-Martín, G., de la Torre, C.: The duration of the interphase periods at different temperatures in root tip cells. Cytobiologie 3, 367–371 (1971).
—, López-Sáez, J. F., Giménez-Martín, G.: Inhibition of cytokinesis, bimitosis and polymitosis. Fiton 21, 157–165 (1964).
Gurdon, J. B.: On the origin and persistence of a cytoplasmic state inducing nuclear DNA synthesis in frogs eggs. Proc. nat. Acad. Sci. (Wash.) 58, 545–552 (1967).
Harris, H.: Behaviour of differentiated nuclei in heterokaryons of animal cells from different species. Nature (Lond.) 206, 583–588 (1965).
—: The reactivation of the red cell nucleus. J. Cell Sci. 2, 23–32 (1967).
—: Nucleus and cytoplasm. Oxford: Clarendon Press (1968).
Heneen, W. K.: In situ analysis of cultured Potorous cells. I. DNA synthesis and mitotic dynamics in bi- and multinucleate cells. Hereditas (Lund) 67, 221–250 (1971).
Howard, A., Pelc, S. R.: Synthesis of desoxyribonucleic acid in normal and irradiated cells and its relation to chromosome breakage. Heredity (Suppl.) 6, 261–274 (1953).
Jacobson, C. O.: Reactivation of DNA synthesis in mammalian neuron nuclei after fusion with cells of an undifferentiated fibroblast line. Exp. Cell Res. 53, 316–318 (1968).
Johnson, R. T., Harris, H.: DNA synthesis and mitosis in fused cells I. HeLa homokaryons. J. Cell Sci. 5, 603–624 (1969).
—: DNA synthesis and mitosis in fused cells. II. HeLa chick erythrocyte heterokaryons. J. Cell Sci. 5, 625–643 (1969).
—: DNA synthesis and mitosis in fused cells. III. HeLa-Ehrlich heterokaryons. J. Cell Sci. 5, 645–697 (1969).
—, Rao, P. N.: Nucleo-cytoplasmic interactions in the achievement of nuclear synchrony in DNA synthesis and mitosis in multinucleate cells. Biol. Rev. 46, 97–155 (1971).
Kihlman, B., Levan, A.: The cytological effect of caffeine. Hereditas (Lund) 35, 109–111 (1949).
Krishan,A., Ray-Chaudhuri, R.: Asynchrony of nuclear development in cytochalasin induced multinucleate cells. J. Cell Biol. 43, 618–621 (1969).
López-Sáez, J. F., Giménez-Martín, G., González-Fernández, A.: Nuclear fusion in somatic cells — a new mechanism of polyploidization. Fiton 22, 1–5 (1965).
Oftebro, R., Wolf, I.: Mitosis of bi- and multinueleate HeLa cells. Exp. Cell Res. 48, 39–52 (1967).
Rao, P. N., Johnson, R. T.: Mammalian cell fusion: Studies on the regulation of DNA synthesis and mitosis. Nature (Lond.) 225, 159–164 (1970).
Sandbery, A. A., Sofuni, T., Takagi, N., Moore, G. E.: Chronology and pattern of human chromosome replication, IV. Autoradiographic studies of binucleate cells. Proc. nat. Acad. Sci. (Wash.) 56, 105–110 (1966).
Thompson, L. R., McCarthy, B. J.: Stimulation of nuclear DNA and RNA synthesis by cytoplasmic extracts in vitro. Biochem. biophys. Res. Commun. 30, 166–172 (1968).
Tjio, J., Levan, A.: The use of oxiquinoline in chromosome analysis. Ann. Estac. Aula Dei 2, 21–64 (1950).
Yamanaka, T., Okada, Y.: Cultivation of fused cells resulting from treatment of cells HVJ. I. Synchronization of the stages of DNA synthesis of nuclei involved in fused multinucleate cells. Biken's J. 2, 159–175 (1966).
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González-Fernández, A., Giménez-Martín, G., Díez, J.L. et al. Interphase development and beginning of mitosis in the different nuclei of polynucleate homokaryotic cells. Chromosoma 36, 100–111 (1971). https://doi.org/10.1007/BF00326425
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DOI: https://doi.org/10.1007/BF00326425