Randomness: Identical Cells, Different Decisions
Increasing crop yields will become a larger priority as the population grows and the amount of farmland decreases. Adrienne H.K. Roeder, Weill Institute for Cell and Molecular Biology/School of Integrative Plant Science is studying a natural mechanism that, with enhancements, may help increase that yield. The cells in the edible parts of corn, beans, rice, wheat, and peas undergo a specialized process called endoreduplication, where cells replicate their DNA many times. But when geneticists try to increase endoreduplication, they find that the response of seemingly identical cells is somewhat random: some cells respond strongly, some moderately, and some not at all—in the same proportions from plant to plant. This observation raises one of the biggest questions in developmental biology: how do identical cells make different decisions? With this CAREER award, Roeder will investigate how random molecular differences affect cells’ endoreduplication—and how randomness, surprisingly, may be necessary for reproducible development.
Roeder and her team will use sepals of the flower Arabidopsis thaliana, which have accessible epidermal cells for live imaging of endoreduplication, and will investigate the role of a transcription factor, Arabidopsis thaliana MERISTEM LAYER1 (ATML1), in driving endoreduplication. Specific goals include uncovering the molecular mechanism through which ATML1 induces endoreduplication as well as how ATML1 feedback loops amplify ATML1 expression. Students at Cornell, as well as local middle school students, will receive training in image analysis and computational skills.