Meeting Abstract

S3.3-2  Saturday, Jan. 4 14:00  Heterogeneity in planarian neoblasts by single cell analysis VAN WOLFSWINKEL, JC*; WAGNER, DE; REDDIEN, PW; Whitehead Institute for Biomedical Research – MIT, Cambridge; Whitehead Institute for Biomedical Research – MIT, Cambridge; Whitehead Institute for Biomedical Research – MIT, Cambridge josien@wi.mit.edu

Planarians have a legendary capacity for adult regeneration that is mediated by a class of cells referred to as neoblasts. Neoblasts have been historically described based on their morphology, their radiation sensitivity and their capacity to divide. Recently it was found that at least part of the neoblast population is made up of pluripotent stem cells. Gene expression analysis by in situ hybridization has shown that all neoblasts share the expression of numerous genes, among which homologs of several known stem cell markers. However several other genes are expressed only in subsets of the neoblasts. It is currently unclear whether these differences in gene expression reflect the presence of several functional subclasses, or whether all neoblasts are part of one more or less homogeneous population. To address this question we used single cell transcriptional profiling to obtain “gene expression fingerprints” of several hundreds of cells from the neoblast population. These fingerprints suggest that multiple different classes of cells are present within the neoblast population, an observation central for defining the molecular basis for both cellular pluripotency and stem cell differentiation in planarian regeneration. We will discuss key molecular and cellular attributes of defined neoblast classes, including their localization, their potency, and their responses to wounds.