Evaluation Summary:
This paper will be of great interest to scientists within the fields of developmental biology and evolution, as well as to researchers that generally use the sea urchin as a model system or those employing single-cell mRNA-sequencing technology. The work provides a comprehensive analysis of the cell state specification of a whole deuterostome organism and proof of principle of the use of single-cell sequencing to identity deep homologies of cell type.
(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1, #2, and #3 agreed to share their names with the authors.)