Endoreduplication in higher plants

Cell polyploidisation can be achieved by endoreduplication, which consists of one or several rounds of DNA synthesis in the absence of mitosis. As a c onsequence, chromosomes with 2(n) chromatids are produced without change in the chromosome number. Endoreduplication is the most common mode of polypl oidisation in plants and can be found in many cell types, especially in tho se undergoing differentiation and expansion. Although accumulating data rev eal that this process is developmentally regulated, it is still poorly unde rstood in plants. At the molecular level, the increasing knowledge on plant cell cycle regulators allows the acquisition of new tools and clues to und erstand the basis of endoreduplication control and, in particular, the swit ch between cell proliferation and cell differentiation.