First published online March 1, 2007
Development 134, 602e (2007)
© The Company of Biologists Limited
A death sentence for neuroblasts
What causes Drosophila larval neuroblasts to self-renew with each
round of cell division? Insights into this are not only of interest to
neurobiologists but also to stem cell researchers. Polycomb group (PcG) genes
in mammals are known to regulate stem cell fate and proliferation. Now on
p. 1091 of this issue,
Bello et al. show that mutations in five of the Drosophila PcG genes
increase the expression of the posterior Hox genes abd-A and
Abd-B and subsequently induce neuroblast death. This phenotype is
rescued by blocking apoptosis. The segmental determination and lineage, but
not cell death, of abdominal secondary neuroblasts relies on posterior Hox
gene expression. Thus, PcG genes regulate neurogenesis differently in varying
developmental contexts. The contributions that other known PcG target genes,
such as cell cycle regulators, make in this setting remain to be determined.
Individual PcG genes regulate different processes both in mammals and flies;
however, the deregulation of Hox gene expression is a common feature of PcG
mutants.
Related articles in Development:
- Polycomb group genes are required for neural stem cell survival in postembryonic neurogenesis of Drosophila
- Bruno Bello, Niklaus Holbro, and Heinrich Reichert
Development 2007 134: 1091-1099.
[Abstract]
[Full Text]
