Abstract

Somitogenesis is regulated by a molecular oscillator which drives dynamic gene expression within the PSM with a periodicity tightly coupled to somite formation. Previous mathematical models that invoke the mechanism of delayed negative feedback predict the oscillation period depends on the sum of delays in negative-feedback loops and the inhibitor half-lives. We develop a model to explore the possibility positive feedback also plays a role. The model predicts increasing the half-life of the positive regulator, Notch intracellular domain (NICD), can lead to elevated NICD levels and an increase in the oscillation period. To test this, we investigate a phenotype induced by various small molecule inhibitors in which the clock is slowed. We observe elevated levels and prolonged half-life of NICD. Reducing NICD production rescues these effects. These data provide the first indication tight control of the turnover of positive as well as negative regulators of the clock determines its periodicity.

Article and author information

Author details

  1. Guy Wiedermann

    Division of Cell and Developmental Biology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Robert Alexander Bone

    Division of Cell and Developmental Biology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Joana Clara Silva

    Division of Cell and Developmental Biology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Mia Bjorklund

    Division of Cell and Developmental Biology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Philip Murray

    Division of Mathematics, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. J Kim Dale

    Division of Cell and Developmental Biology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
    For correspondence
    j.k.dale@dundee.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Janet Rossant, University of Toronto, Canada

Ethics

Animal experimentation: This study was performed under a home office license issued to Dr Kim Dale and under the regulations of the home office Animal Welfare ACT. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols of the University of Dundee. The protocol was approved by the ethical committee of the University of Dundee. Every effort was made to minimize suffering.

Version history

  1. Received: December 8, 2014
  2. Accepted: September 2, 2015
  3. Accepted Manuscript published: September 10, 2015 (version 1)
  4. Version of Record published: October 13, 2015 (version 2)

Copyright

© 2015, Wiedermann et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 2,301
    views
  • 493
    downloads
  • 26
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Guy Wiedermann
  2. Robert Alexander Bone
  3. Joana Clara Silva
  4. Mia Bjorklund
  5. Philip Murray
  6. J Kim Dale
(2015)
A balance of positive and negative regulators determines the pace of the segmentation clock
eLife 4:e05842.
https://doi.org/10.7554/eLife.05842

Share this article

https://doi.org/10.7554/eLife.05842

Further reading

    1. Computational and Systems Biology
    2. Developmental Biology
    Gang Xue, Xiaoyi Zhang ... Zhiyuan Li
    Research Article

    Organisms utilize gene regulatory networks (GRN) to make fate decisions, but the regulatory mechanisms of transcription factors (TF) in GRNs are exceedingly intricate. A longstanding question in this field is how these tangled interactions synergistically contribute to decision-making procedures. To comprehensively understand the role of regulatory logic in cell fate decisions, we constructed a logic-incorporated GRN model and examined its behavior under two distinct driving forces (noise-driven and signal-driven). Under the noise-driven mode, we distilled the relationship among fate bias, regulatory logic, and noise profile. Under the signal-driven mode, we bridged regulatory logic and progression-accuracy trade-off, and uncovered distinctive trajectories of reprogramming influenced by logic motifs. In differentiation, we characterized a special logic-dependent priming stage by the solution landscape. Finally, we applied our findings to decipher three biological instances: hematopoiesis, embryogenesis, and trans-differentiation. Orthogonal to the classical analysis of expression profile, we harnessed noise patterns to construct the GRN corresponding to fate transition. Our work presents a generalizable framework for top-down fate-decision studies and a practical approach to the taxonomy of cell fate decisions.

    1. Computational and Systems Biology
    2. Genetics and Genomics
    Weichen Song, Yongyong Shi, Guan Ning Lin
    Tools and Resources

    We propose a new framework for human genetic association studies: at each locus, a deep learning model (in this study, Sei) is used to calculate the functional genomic activity score for two haplotypes per individual. This score, defined as the Haplotype Function Score (HFS), replaces the original genotype in association studies. Applying the HFS framework to 14 complex traits in the UK Biobank, we identified 3619 independent HFS–trait associations with a significance of p < 5 × 10−8. Fine-mapping revealed 2699 causal associations, corresponding to a median increase of 63 causal findings per trait compared with single-nucleotide polymorphism (SNP)-based analysis. HFS-based enrichment analysis uncovered 727 pathway–trait associations and 153 tissue–trait associations with strong biological interpretability, including ‘circadian pathway-chronotype’ and ‘arachidonic acid-intelligence’. Lastly, we applied least absolute shrinkage and selection operator (LASSO) regression to integrate HFS prediction score with SNP-based polygenic risk scores, which showed an improvement of 16.1–39.8% in cross-ancestry polygenic prediction. We concluded that HFS is a promising strategy for understanding the genetic basis of human complex traits.