First published online January 27, 2005
Development 132, 401e (2005)
© The Company of Biologists Limited
Found: an elusive member of the Hh signalling pathway
Despite the remarkable conservation of the Hedgehog (Hh) signalling pathway
through evolution, Costal2 (Cos2), a vital component of this pathway in flies,
has escaped detection in vertebrates. But now, Tay et al. report the
identification of the first vertebrate homologue of Cos2, which they cloned
from zebrafish by virtue of its sequence similarity to fly Cos2 (see p.
625). In morpholino
knockdown experiments, the authors show that decreased cos2 levels
cause ectopic Hh signalling, as expected from its role in flies where this
kinesin-related protein is thought to assemble a protein complex, ultimately
leading to the Cubitus interruptus (Ci)-mediated repression of Hh target
genes. In vitro, zebrafish Cos2 can complex with Gli1, the fly homologue of
Ci. Together with the mouse and human Cos2-like sequences reported here, these
findings should shed new light on the mechanics of Hh signalling in
vertebrates.
Related articles in Development:
- A homologue of the Drosophila kinesin-like protein Costal2 regulates Hedgehog signal transduction in the vertebrate embryo
- Shang Yew Tay, Philip W. Ingham, and Sudipto Roy
Development 2005 132: 625-634.
[Abstract]
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