Xbp1 and Brachyury establish an evolutionarily conserved subcircuit of the notochord gene regulatory network
- New York University, United States
Abstract
Gene regulatory networks coordinate the formation of organs and structures that compose the evolving body plans of different organisms. We are using a simple chordate model, the Ciona embryo, to investigate the essential gene regulatory network that orchestrates morphogenesis of the notochord, a structure necessary for the proper development of all chordate embryos. Although numerous transcription factors expressed in the notochord have been identified in different chordates, several of them remain to be positioned within a regulatory framework. Here we focus on Xbp1, a transcription factor expressed during notochord formation in Ciona and other chordates. Through the identification of Xbp1-downstream notochord genes in Ciona, we found evidence of the early co-option of genes involved in the unfolded protein response to the notochord developmental program. We report the regulatory interplay between Xbp1 and Brachyury, and by extending these results to Xenopus, we show that Brachyury and Xbp1 form a cross-regulatory subcircuit of the notochord gene regulatory network that has been consolidated during chordate evolution.
Data availability
The complete dataset has been deposited into the NCBI Gene Expression Omnibus, under accession number GSE46751
Article and author information
Author details
Jean-Pierre Saint-Jeannet
Funding
National Institutes of Health (R03HD098395)
- Yushi Wu
- Arun Devotta
- Diana S José-Edwards
- Jamie E Kugler
- Lenny J Negrón-Piñeiro
- Karina Braslavskaya
- Jermyn Addy
- Anna Di Gregorio
National Institutes of Health (graduate student training grant,T32HD007520)
- Lenny J Negrón-Piñeiro
National Institutes of Health (graduate student training grant,T32GM008539)
- Diana S José-Edwards
National Institutes of Health (Administrative supplement R03HD098395-02S1)
- Lenny J Negrón-Piñeiro
New York University Center for Skeletal and Craniofacial Biology (Pilot grant)
- Yushi Wu
- Arun Devotta
- Diana S José-Edwards
- Jamie E Kugler
- Lenny J Negrón-Piñeiro
- Karina Braslavskaya
- Jermyn Addy
- Jean-Pierre Saint-Jeannet
- Anna Di Gregorio
National Institutes of Health (Center Core Grant for the NYU CSCB 1P30DE020754)
- Jean-Pierre Saint-Jeannet
National Institutes of Health (Center Grant for NYU Langone Health DART Microscopy Laboratory P30CA016087)
- Yushi Wu
- Anna Di Gregorio
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Procedure minimizing discomfort and pain - only applicable to XenopusThe collection of eggs from females primed with chorionic gonadotropin hormone requires minimum procedures occasioning virtually no pain or suffering. Surgical dissection of the testes is performed on euthanized males (see below), preventing discomfort.Methods of euthanasiaMale frogs will be euthanized during the procedure, in a two-step process. They will be initially anesthetized by immersion into a solution of ethyl amino benzoate (tricaine/MS222) and then a pithing procedure of the brain and the spinal cord will be used to terminate the animal. After pithing, respiration ceases signaling death. Female frogs will be euthanized in a similar manner when no longer producing viable eggs or appear ill.
Copyright
© 2022, Wu 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.
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Xbp1 and Brachyury establish an evolutionarily conserved subcircuit of the notochord gene regulatory network
eLife 11:e73992.
https://doi.org/10.7554/eLife.73992
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