Abstract
Higher plants are constructed from billions of cells that have variable sizes and shapes. What controls these important cellular features are not well understood, but one aspect that influences the final size of cells is the total amount of nuclear DNA, or ploidy. In Arabidopsis, an increase in nuclear DNA content is mediated by a process called endoreduplication, an alternative cell cycle in which cells continue to replicate their chromosomal DNA without undergoing cell division. Previous studies suggest that phytohormones can affect ploidy levels, however the molecular mechanisms underlying this process is largely unknown. To gain new insights into the regulation of endoreduplication, we analyzed physiological effect of auxin, a phytohormone known to control the mitotic cell cycle. Our current hypothesis is that auxin is involved in some pathways that regulate the endoreduplication.
