First published online November 24, 2004
Development 131, 2401e (2004)
© The Company of Biologists Limited
Hox-mediated neuronal patterning: death to pioneers
Apoptosis helps to control cell numbers throughout development. In the
developing nervous system of vertebrate embryos, neurons apoptose after
differentiating and extending their axons; in invertebrate embryos, apoptosis
typically occurs immediately after neuron generation. On p.
6093, Miguel-Aliaga
and Thor provide the first example of the apoptosis of differentiated neurons
in the Drosophila embryo. They show that Drosophila dMP2 and
MP1 pioneer neurons undergo apoptosis in anterior segments at late embryonic
stages, after they have fulfilled their duties as pioneer neurons. Apoptosis
in posterior segments is prevented by the Hox gene Abdominal B, which
represses the death activators reaper and grim in a
cell-autonomous manner. These results reveal a new mechanism – selective
elimination of mature neurons – by which Hox positional information
controls neuronal architecture along the anteroposterior axis. A similar
mechanism could act in vertebrate embryos, suggest the researchers.
Related articles in Development:
- Segment-specific prevention of pioneer neuron apoptosis by cell-autonomous, postmitotic Hox gene activity
- Irene Miguel-Aliaga and Stefan Thor
Development 2004 131: 6093-6105.
[Abstract]
[Full Text]
