Itai Yanai, Ph.D.
Director, Institute for Computational Medicine
Professor, Biochemistry and Molecular Pharmacology
The New York University School of Medicine

“Studying development and evolution using single-cell RNA-Seq” 

Evolution and development are two inherently intertwined processes. As the embryo develops it does so in ways that both reflect past constraints and bias the future evolution of the species. While research exploiting this insight typically studies individual genes, transcriptomic analyses have sparked a new wave of discoveries. In this opinion piece, I review the evidence arising from transcriptomics on the topics of the evolution of germ layers, the phylotypic stage, and developmental constraints. The spatiotemporal pattern of gene expression across germ layers provides evidence that the endoderm was the first germ layer to evolve. Comparing transcriptome dynamics throughout developmental time across distant species reveals a mid-developmental transition under strong developmental constraints. These studies highlight the efficiency of exploratory data analysis using computational tools and comparative approaches for discovery.

Reading material:

1. Michal Levin, Leon Anavy, Itai Yanai, et al.  The mid-developmental transition and the evolution of animal body plans.  Nature 531, 637-641 (31 March 2016).
2. Itai Yanai.  Development and Evolution through the Lens of Global Gene Regulation.  Trends in Genetics, Volume 34, Issue 1, January 2018, pp 11-20.