Developmentally regulated cell death plays an essential role during embryo development. It is required to remove unwanted and damaged cells. We have used time-lapse microscopy to study cell death in Drosophila embryos. Cell death in Drosophila embryos is patterned both in space and developmental time. Cell death is also required to correct developmental errors, such as: alterations in the embryo's fate map and increased cell density caused by ectopic cell division. We are using a proteomics approach to identify early protein changes during cell death induction. We have discovered a new key regulator that is required for cell death.

We are also studying cell engulfment, the final step in cell death. Using a novel, in-vivo engulfment reporter, we recently discovered that engulfment of dying cells is caspase independent. We are currently searching for regulators of cell engulfment.

Shown here is a time-lapse movie of the head region of a wild-tpye embryo injected with acridine orange to reveal dying cells-the fluorescent spots. Macrophages that have engulfed dying cells are seen as clusters of rapidly moving, fluorescent spots.