Abstract
Chromosomal DNA fiber autoradiography was used to examine the replicon properties of root-tip meristem cells of Helianthus annuus intact seedlings grown at temperatures from 10 to 38° C and those of root-tip cells grown in vitro at 23°. The average replicon size was approximately 22 μm and it did not change with temperature nor when the roots were grown in culture. The average fork rate was 6 μm/h at 10° and it rose gradually to 12 μm/h at 38°. The responses of replication fork movement and of the duration of S to temperature were of three types: those in which change in fork rate was primarily (more than 90%) responsible for change in the duration of S, those in which the fork rate remained constant while S increased nearly twofold, and those in which the duration of S increased even though the replication forks were moving faster. The first type of response listed was observed at temperatures from 20 to 35°, the second type listed was observed at 10 to 15°, and the third, was produced at 38°.
Similar content being viewed by others
References
Burholt, D.R., Van't Hof, J.: Quantitative thermal-induced changes in growth and cell population kinetics of Helianthus roots. Amer. J. Bot. 58, 386–393 (1971)
Conger, A.D.: A simple liquid culture method for growing plants. Proc. Fla. State Hort. Soc. 77, 536–537 (1964)
Edenberg, H.J., Huberman, J.A.: Eukaryotic chromosome replication. Ann. Rev. Genet. 9, 245–284 (1975)
Huberman, J.A., Riggs, A.D.: On the mechanism of DNA replication in mammalian chromosomes. J. molec. Biol. 32, 327–341 (1968)
Huberman, J.A., Tsai, A.: Direction of DNA replication in mammalian cells. J. molec. Biol. 75, 5–12 (1973)
Planck, S.R., Mueller, G.C.: Deoxyribonucleic acid chain growth and organization of replicating units in HeLa cells. Biochemistry (Wash.) 16, 1808–1813 (1977)
Prescott, D.M.: Replication of eukaryotic cells. New York: Academic Press 1976
Quastler, H., Sherman, F.G.: Cell population kinetics in the intestinal epithelium of the mouse. Exp. Cell Res. 17, 420–438 (1959)
Rost, T.L., Van't Hof, J.: Radiosensitivity, RNA, and protein metabolism of “leaky” and arrested cells in sunflower root meristems (Helianthus annuus) Amer. J. Bot. 60, 172–181 (1973)
Van't Hof, J.: Replicon size and rate of fork movement in early S of higher plant cells (Pisum sativum). Exp. Cell Res. 103, 395–403 (1976a)
Van't Hof, J.: DNA fiber replication of chromosomes of pea root cells terminating S. Exp. Cell Res. 99, 47–56 (1976b)
Van't Hof, J., Bjerknes, C.A., Clinton, J.H.: Replication of chromosomal DNA fibers of root meristem cells of higher plants. In: Molecular biology of plants (I. Rubenstein and R.L. Phillips, eds.). New York: Academic Press (in press, 1978)
Van't Hof, J., Rost, T.L.: Cell proliferation in complex tissue: the control of the mitotic cycle of cell populations in the cultured root meristem of sunflower (Helianthus). Amer. J. Bot. 59, 769–774 (1972)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Van't Hof, J., Bjerknes, C.A. & Clinton, J.H. Replicon properties of chromosomal DNA fibers and the duration of DNA synthesis of sunflower root-tip meristem cells at different temperatures. Chromosoma 66, 161–171 (1978). https://doi.org/10.1007/BF00295137
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00295137