Geminin coordinates cell cycle and developmental control.
Growth and differentiation are two major themes in embryonic development. Numerous cell divisions have to be regulated on the path from a unicellular embryo, the zygote, to the multicellular structures of a mature being. Numerous functions, specializations and cellular identities have to be generated, in order to form a complex and mature animal. Numerous mechanisms have to control the correct assignment and acquisition of cellular fates, as well as the right timing and allocation of cells. Therefore, a strict coordination has to occur between embryonic patterning and the cell cycle. From this point of view, dual roles or mutual interactions of typical proliferation and developmental control genes are likely. Recently, new light was shed on these issues by identifying the nuclear protein Geminin as a molecular coordinator between the cell cycle and axial patterning. We summarize the role of Geminin in cell cycle, in the embryonic patterning controlled by Hox genes, providing insights into cell cycle regulators in embryonic development, and conversely, typical developmental control genes in cell cycle regulation.