First published online December 21, 2007
Development 135, 203e (2008)
© The Company of Biologists Limited
Heads down with Hox
Conserved Hox transcription factors direct the formation of distinct
structures along the anteroposterior axis of bilaterian animals. Given that
Hox genes probably all derive from a single unique gene by duplication, might
they also share a common function? On
p. 291, Coiffier and
co-workers propose that this is the case by showing that all
Drosophila central and posterior (CP) Hox genes repress head
formation in the fly's trunk, in addition to their well-known roles in segment
identity. Hox genes of many species fall into CP and anterior classes based on
their expression pattern and sequence similarities. The researchers report
that, in Drosophila, the central Hox proteins (including Antennapedia
and Ultrabithorax) and the posterior Hox protein Abdominal B prevent the
expression of the head-specific gene optix in the trunk. Furthermore,
several non-Hox genes, including Teashirt and Wingless/Wnt,
contribute to this repression. The researchers propose, therefore, that an
early function of Hox genes was to repress the head and that novel Hox
functions that specialise the trunk appeared later.
Related articles in Development:
- Common functions of central and posterior Hox genes for the repression of head in the trunk of Drosophila
- Delphine Coiffier, Bernard Charroux, and Stephen Kerridge
Development 2008 135: 291-300.
[Abstract]
[Full Text]