You are not currently logged in.
Access your personal account or get JSTOR access 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.
A Change in the Rate of Transcription of a Eukaryotic Gene in Response to Cyclic AMP
J. G. Williams, A. S. Tsang and H. Mahbubani
Proceedings of the National Academy of Sciences of the United States of America
Vol. 77, No. 12, [Part 2: Biological Sciences] (Dec., 1980), pp. 7171-7175
Published by: National Academy of Sciences
Stable URL: http://www.jstor.org/stable/9724
Page Count: 5
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
The plasmid pDd812 contains the DNA copy of an mRNA sequence from Dictyostelium discoideum that undergoes first an increase and then a decrease in concentration during the first few hours of differentiation. We have recently shown that the mRNA sequence complementary to pDd812 encodes discoidin I, a developmentally regulated lectin that may play a role in cellular cohesion. By using pDd812 as a hybridization probe, we found that addition of cyclic AMP during the first few hours of development inhibited the accumulation of discoidin I mRNA. By measuring the rate of transcription in isolated nuclei, we showed that, at least in part, this inhibition results from a rapid and specific reduction in the rate of transcription of the discoidin I gene. Addition of high external concentrations of cAMP is known to increase the intracellular concentration to a level normally found later in development. This natural increase in cAMP concentration occurs at the time during development when transcription of the discoidin I gene ceases. We suggest, therefore, that changes in the intracellular concentration of cAMP act at the level of transcription to control gene expression during development. This hypothesis is supported by our observation that several poly(A)+RNA sequences that normally accumulate after transcription of the discoidin I gene has ceased are synthesized prematurely in cells exposed to exogenous cAMP.
Proceedings of the National Academy of Sciences of the United States of America © 1980 National Academy of Sciences