Heparan sulphate proteoglycans (HSPGs) – extracellular molecules that bind key secreted morphogens, including Wingless (Wg) and Hedgehog (Hh)– are crucial for normal metazoan development. But pinning down their roles in different signalling pathways can be extremely difficult. For example, it has been recently debated (see Development 131, 2509), whether the fly HSPGs,Dally and Dally-like protein (Dlp), function in both Hh and Wg, or just in Hh,signalling. Now, Franch-Marro et al., on p. 659, conclusively answer this question. By generating dally and dlp null mutant flies, they show that neither Dally nor Dlp is essentially required for embryonic Wg signalling. If wg expression is sustained in double mutant embryos, Wg pathway activation still occurs. By contrast, Dlp has a crucial role in regulating the range of Wg signalling in the wing imaginal discs of developing larvae. The authors report that in the absence of Dlp,short-range Wg signalling in this tissue increases at the expense of long-range signalling. To explain this, they propose that here Dlp functions by passing bound Wg onto neighbouring cells rather than to signalling receptors on the same cell, but how this actually occurs requires more investigation. Dally appears to act as a non-essential co-receptor that binds and presents Wg to signalling receptors on the same cell. On p. 667, Han et al. also shed light on Dally and Dlp functions in wing development. They report that it is predominantly the combined actions of Dally and Dlp that shape the Wg gradient in the developing fly wing by a restricted diffusion mechanism. Contradicting previous findings, they also report that the Wg receptor Fz2 appears to have only a modest role in this process.
Dally and Dally-like functions: some questions answered
Dally and Dally-like functions: some questions answered. Development 15 February 2005; 132 (4): e404. doi:
Download citation file:
Advertisement
Cited by
Call for papers: Uncovering Developmental Diversity
Development invites you to submit your latest research to our upcoming special issue: Uncovering Developmental Diversity. This issue will be coordinated by our academic Editor Cassandra Extavour (Harvard University, USA) alongside two Guest Editors: Liam Dolan (Gregor Mendel Institute of Molecular Plant Biology, Austria) and Karen Sears (University of California Los Angeles, USA).
Choose Development in 2024
In this Editorial, Development Editor-in-Chief James Briscoe and Executive Editor Katherine Brown explain how you support your community by publishing in Development and how the journal champions serious science, community connections and progressive publishing.
Journal Meeting: From Stem Cells to Human Development
Register now for the 2024 Development Journal Meeting From Stem Cells to Human Development. Early-bird registration deadline: 3 May. Abstract submission deadline: 21 June.
Pluripotency of a founding field: rebranding developmental biology
This collaborative Perspective, the result of a workshop held in 2023, proposes a set of community actions to increase the visibility of the developmental biology field. The authors make recommendations for new funding streams, frameworks for collaborations and mechanisms by which members of the community can promote themselves and their research.
Read & Publish Open Access publishing: what authors say
We have had great feedback from authors who have benefitted from our Read & Publish agreement with their institution and have been able to publish Open Access with us without paying an APC. Read what they had to say.