title: Planarian Epidermal Stem Cells Respond to Positional Cues to Promote Cell-Type Diversity.
abstract: Successful regeneration requires that progenitors of different lineages form the appropriate missing cell types. However, simply generating lineages is not enough. Cells produced by a particular lineage often have distinct functions depending on their position within the organism. How this occurs in regeneration is largely unexplored. In planarian regeneration, new cells arise from a proliferative cell population (neoblasts). We used the planarian epidermal lineage to study how the location of adult progenitor cells results in their acquisition of distinct functional identities. Single-cell RNA sequencing of epidermal progenitors revealed the emergence of distinct spatial identities as early in the lineage as the epidermal neoblasts, with further pre-patterning occurring in their post-mitotic migratory progeny. Establishment of dorsal-ventral epidermal identities and functions, in response to BMP signaling, required neoblasts. Our work identified positional signals that activate regionalized transcriptional programs in the stem cell population and subsequently promote cell-type diversity in the epidermis.
authors.affiliation: Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
authors.forename: Omri
authors.initials: O
authors.lastname: Wurtzel
authors.affiliation: Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
authors.forename: Isaac M
authors.initials: IM
authors.lastname: Oderberg
authors.affiliation: Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA. Electronic address: reddien@wi.mit.edu.
authors.forename: Peter W
authors.initials: PW
authors.lastname: Reddien
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D019521:Body Patterning / Q000235:genetics; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics; D019070:Cell Lineage; D000078404:Epidermal Cells; D004817:Epidermis / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D008938:Mitosis / Q000235:genetics; D008954:Models, Biological; D010932:Planarians / Q000166:cytology*; D034622:RNA Interference; D017423:Sequence Analysis, RNA; D015398:Signal Transduction / Q000235:genetics; D059010:Single-Cell Analysis; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D015415:Biomarkers; D019485:Bone Morphogenetic Proteins; D014157:Transcription Factors
keywords: BMP signaling; epidermis; neoblast; patterning; planaria; progenitors; regeneration; single-cell sequencing; stem cells