Programmed cell death AS A MECHANISM OF NEURAL DEVELOPMENT

THE SWITCH FROM DIVISION TO APOPTOSIS OCCURS AT A DEFINED TIME POINT: new EVIDENCE in Drosophila

The original research paper (Bello B.C., et al. A pulse of the Drosophila Hox protein Abdominal-A schedules the end of neural proliferation via neuroblast apoptosis Neuron 37, 209-219, 2003) shows new evidence for the role of apoptosis, or programmed cell death, in regulating neural development by a process linked to axial patterning in Drosophila. The change from proliferation to death doesn’t seem related to a defined phase of the cell cycle, but it exactly occurs at one point in time during larval development. Apoptosis was observed in abdominal neuroblasts, while their thoracic counterpart didn’t undergo the same destiny. This regional difference seems to depend on the control of the cell numbers linked to axial patterning mechanisms. The authors studied through deletion and ectopic expression the abdominal A (abdA) gene, one among Hox family of homeobox transcription factors, concluding that abdA is probably a factor that signals immature neurons to stop dividing.

Apoptotic control of the neuroblast proliferation might be a widespread strategy of development in other species.

BM&L-March 2003