Adult pluripotent stem cell specification during planarian embryogenesis

Division Of Basic Sciences - Nci

Investigators

Abstract

This project began as a team-driven effort led by NCI iCURE Postdoctoral Researcher Dr. Kayla Titialii-Torres, with the assistance of postbaccalaurate researcher Clover Stubbert and bioinformaticist Laura Paez Baena. With the departure of these three team members, I am now restructuring the project to accommodate a change in model species and personnel. Our working hypothesis is that cycling piwi-1+ cells in early embryos are the cellular antecedents of adult pluripotent stem cells (aPSCs). We posit that stage-dependent changes in gene expression correlate, and are potentially causative, in effecting the embryonic to adult pluripotency transition. We collected single cell RNA-Seq whole-embryo atlases for nine developmental stages encompassing this key cell fate transition and construction of the adult anatomy. In the future, we will characterize the changing lineage repertoire for the piwi-1+ cells during embryogenesis, and in performing trajectory analysis to generate testable hypothesis about key regulators of this process. In tandem, we have been developing functional assays that will answer key questions about piwi-1+ cell behavior during embryogenesis, including whether cells at different stages are clonogenic and multipotent, and whether pluripotency is an individual or collective property of piwi-1+ cells at different stages. These studies will also shed light on the contribution and regulation of nascent aPSCs to the establishment of livelong whole-body regenerative abilities late in embryogenesis.