Christian Lehner

Cell cycle, cell divisions

An adult human is built from roughly 1013 cells. All of these cells are generated by cell divisions, starting from a single cell, the fertilized egg (zygote). During development, cell divisions have to be controlled in space and time so that sufficient cells are available at the stage when a particular structure or organ is formed. In replacement tissues (like skin, intestine, blood), carefully controlled cell proliferation continues during adult life in order to compensate for the decay of aged cells. Malfunction of the control mechanisms results in overproliferation of cells, the hallmark of cancer. Our research is focussed on the analysis of the molecular mechanisms which control cell divisions. In comparison to humans, the relatively simple fruit fly Drosophila melanogaster allows for more powerful genetic approaches. We address cell biological and developmental issues. Which mechanisms are crucial for the correct inheritance of the genetic information (chromosomes) to daughter cells during meiotic and mitotic divisions? How does the developmental control of rate-limiting cell cycle regulators (cyclins, cdk inhibitors) govern entry into and exit from the cell division cycle?