ReviewDevelopmental biology2017
John Saunders' ZPA, Sonic hedgehog and digit identity - How does it really all work?
Review in Developmental biology, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
13 citing papers in PubMed.
- Evolution of limb and digit identity genes since the tetrapod ancestor.Nature communications · 2026Article
- Inherited non-syndromic polydactyly in a Berber and Arabian-Berber horse family.Equine veterinary journal · 2025Article
- Dual Bmp-negative feedback loops modulate function of both AER and ZPA to buffer and constrain postaxial digit number.Proceedings of the National Academy of Sciences of the United States of America · 2025Article
- G Protein-Coupled Receptor Signal Intersection at the Primary Cilium.BioEssays : news and reviews in molecular, cellular and developmental biology · 2025Review
- Emerging mechanistic understanding of cilia function in cellular signalling.Nature reviews. Molecular cell biology · 2024Review
- Paralog-specific TTC30 regulation of Sonic hedgehog signaling.Frontiers in molecular biosciences · 2023Article
- Evolutionary genetics of flipper forelimb and hindlimb loss from limb development-related genes in cetaceans.BMC genomics · 2022Article
- Sonic hedgehog is not a limb morphogen but acts as a trigger to specify all digits in mice.Developmental cell · 2022Article
- Downregulation of Grem1 expression in the distal limb mesoderm is a necessary precondition for phalanx development.Developmental dynamics : an official publication of the American Association of Anatomists · 2022Article
- Reconstruction of the Global Polarity of an Early Spider Embryo by Single-Cell and Single-Nucleus Transcriptome Analysis.Frontiers in cell and developmental biology · 2022Article
- Evidence against tetrapod-wide digit identities and for a limited frame shift in bird wings.Nature communications · 2019Article
- Pattern of fin rays along the antero-posterior axis based on their connection to distal radials.Zoological letters · 2019Article
- Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors.
Funding
Abstract
Among John Saunders' many seminal contributions to developmental biology, his discovery of the limb 'zone of polarizing activity' (ZPA) is arguably one of the most memorable and ground-breaking. This discovery introduced the limb as a premier model for understanding developmental patterning and promoted the concept of patterning by a morphogen gradient. In the 50 years since the discovery of the ZPA, Sonic hedgehog (Shh) has been identified as the ZPA factor and the basic components of the signaling pathway and many aspects of its regulation have been elucidated. Although much has also been learned about how it regulates growth, the mechanism by which Shh patterns the limb, how it acts to instruct digit 'identity', nevertheless remains an enigma. This review focuses on what has been learned about Shh function in the limb and the outstanding puzzles that remain to be solved.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.