You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
DNA Synthesis and Mitosis in Meristems: Requirements for RNA and Protein Synthesis
P. L. Webster and J. Van't Hof
American Journal of Botany
Vol. 57, No. 2 (Feb., 1970), pp. 130-139
Published by: Botanical Society of America, Inc.
Stable URL: http://www.jstor.org/stable/2440504
Page Count: 10
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Following provision of sucrose to starved, stationary phase pea root meristems, G1 and G2 cells enter DNA synthesis and mitosis, respectively. Puromycin (450 μg/ml) and cycloheximide (5 μg/ml) completely prevent this initiation of progression through the cell cycle. Actinomycin D (10 μg/ml) has no effect on the initial entry of G1 and G2 cells into S and mitosis, although later entry is prevented. The resistance of the cells to actinomycin D is lost slowly with time in medium without sucrose, suggesting that an RNA required for the resumption of proliferative activity is being gradually lost. The effects of the inhibitors on transitional and proliferative phase meristem cells indicate that such dividing cells do indeed have sufficient of the requisite RNA for 8-12 hr progression through the cycle, but that protein synthesis is required continuously. It is suggested that this RNA is the one lost slowly during starvation, allowing starved cells to reinitiate progression through the cycle in the presence of actinomycin D.
American Journal of Botany © 1970 Botanical Society of America, Inc.