Cilia are present on most cells of the body and their formation depends on intraflagellar transport (IFT). Mutations that affect IFT lead to altered sonic hedgehog (Shh) signalling, and consequently to limb and neural tube patterning defects in mice. Now, on p. 307, Bradley Yoder and co-workers reveal for the first time that IFT and therefore cilia are also required for normal Indian hedgehog (Ihh) signalling. They made their discovery using a conditional allele of an IFT protein, IFT88/polaris, to disrupt cilia and to investigate the effects on mouse limb development. Although cilia disruption in the ectoderm produces no phenotype, disruption in the mesenchyme results in polydactyly, a loss of anteroposterior digit patterning and a shortening of the proximodistal axis of the limb. Their results show that the digit-patterning phenotypes are associated with disrupted Shh activity. The limb outgrowth defects, however, are due to abrogated Ihh signalling during endochondral bone formation, the first evidence that IFT and normal cilia functioning are required for Ihh signalling.
Indian hedgehog signalling given a lIFT
Indian hedgehog signalling given a lIFT. Development 15 January 2007; 134 (2): e202. doi:
Download citation file:
Advertisement
Cited by
Biologists @ 100 - join us in Liverpool in March 2025

We are excited to invite you to a unique scientific conference, celebrating the 100-year anniversary of The Company of Biologists, and bringing together our different communities. The conference will incorporate the Spring Meetings of the BSCB and the BSDB, the JEB Symposium Sensory Perception in a Changing World and a DMM programme on antimicrobial resistance. Find out more and register by 28 February 2025 to join us in March 2025 in Liverpool, UK.
Call for papers – Lifelong Development: the Maintenance, Regeneration and Plasticity of Tissues

Development invites you to submit your latest research to our upcoming special issue – Lifelong Development: the Maintenance, Regeneration and Plasticity of Tissues. This issue will be coordinated by Guest Editors Meritxell Huch (Max Planck Institute of Molecular Cell Biology and Genetics, Germany) and Mansi Srivastava (Harvard University and Museum of Comparative Zoology, USA), working alongside our team of academic Editors. Submit your articles by 15 May 2025.
A case for broadening our view of mechanism in developmental biology

In this Perspective, B. Duygu Özpolat and colleagues survey researchers on their views on what it takes to infer mechanism in developmental biology. They examine what factors shape our idea of what we mean by ‘mechanism’ and suggest a path forward that embraces a broad outlook on the diversity of studies that advance knowledge in our field.
In preprints
Did you know that Development publishes perspectives on recent preprints? These articles help our readers navigate the ever-growing preprint literature. We welcome proposals for ‘In preprints’ articles, so please do get in touch if you’d like to contribute.