scRNA-sequencing in chick suggests a probabilistic model for cell fate allocation at the neural plate border
- King's College London, United Kingdom
- The Francis Crick Institute, United Kingdom
Abstract
The vertebrate 'neural plate border' is a transient territory located at the edge of the neural plate containing precursors for all ectodermal derivatives: the neural plate, neural crest, placodes and epidermis. Elegant functional experiments in a range of vertebrate models have provided an in-depth understanding of gene regulatory interactions within the ectoderm. However, these experiments conducted at tissue level raise seemingly contradictory models for fate allocation of individual cells. Here, we carry out single cell RNA sequencing of chick ectoderm from primitive streak to neurulation stage, to explore cell state diversity and heterogeneity. We characterise the dynamics of gene modules, allowing us to model the order of molecular events which take place as ectodermal fates segregate. Furthermore, we find that genes previously classified as neural plate border 'specifiers' typically exhibit dynamic expression patterns and are enriched in either neural, neural crest or placodal fates, revealing that the neural plate border should be seen as a heterogeneous ectodermal territory and not a discrete transitional transcriptional state. Analysis of neural, neural crest and placodal markers reveals that individual NPB cells co-express competing transcriptional programmes suggesting that their ultimate identify is not yet fixed. This population of 'border located undecided progenitors' (BLUPs) gradually diminishes as cell fate decisions take place. Considering our findings, we propose a probabilistic model for cell fate choice at the neural plate border. Our data suggest that the probability of a progenitor's daughters to contribute to a given ectodermal derivative is related to the balance of competing transcriptional programmes, which in turn are regulated by the spatiotemporal position of a progenitor.
Data availability
10x single cell RNAseq was carried out in two batches and is available under two separate accession numbers (ArrayExpress: E-MTAB-10408 and E-MTAB-1144). Our NGS alignments and downstream analysis have been wrapped into custom Nextflow pipelines allowing for full reproducibility. For the code used in this analysis, including links to our Docker containers, see our GitHub repository at https://github.com/alexthiery/10x_neural_plate_border. Finally, we have developed a user friendly ShinyApp to allow public exploration of our single cell RNAseq data at https://shiny.crick.ac.uk/thiery_neural_plate_border/.
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/S005536/1)
- Alexandre P Thiery
- Ailin Leticia Buzzi
- Andrea Streit
Biotechnology and Biological Sciences Research Council (BB/R006342/1)
- Alexandre P Thiery
- Ailin Leticia Buzzi
- Andrea Streit
Wellcome Trust (108874/B/15/Z)
- Nicholas M Luscombe
Wellcome Trust (FC001051)
- Chris Cheshire
- Nicholas M Luscombe
- James Briscoe
Cancer Research UK (FC001051)
- Chris Cheshire
- Nicholas M Luscombe
- James Briscoe
Medical Research Council (FC001051)
- Chris Cheshire
- Nicholas M Luscombe
- James Briscoe
Wellcome Trust (108874/Z/15/Z)
- Eva Hamrud
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Thiery 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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scRNA-sequencing in chick suggests a probabilistic model for cell fate allocation at the neural plate border
eLife 12:e82717.
https://doi.org/10.7554/eLife.82717
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