Mechanisms of neuronal death during development--insights from chick motoneurons

During normal development, large numbers of cells undergo a temporally and spatially specific period of programmed cell death (PCD). The study of PCD is an area of intense research in many disciplines, including oncology, immunology and neurobiology. Understanding this process should provide keys to developing therapeutic strategies based on initiating cell death, a desire in cancer therapies, or preventing cell death in neurodegenerative diseases. This somewhat obvious notion pinpoints the purpose of this article. Cell death research blankets many fields contributing to an explosive acquisition of data from many sources. These data however, have not been universally consistent with information relevant to one area, such as mitotically active cancer cells versus that of another area, such as postmitotic neurons. This review article will outline some issues that we currently understand to underlie biochemical and molecular mechanisms mediating neuronal death in the developing CNS. Considering the amount of research currently directed toward understanding the pathways of cell death, we will attempt to identify components that appear to be common in all cell deaths as well as those possibly unique to neuronal death.