title: Wnt, Ptk7, and FGFRL expression gradients control trunk positional identity in planarian regeneration.
abstract: Mechanisms enabling positional identity re-establishment are likely critical for tissue regeneration. Planarians use Wnt/beta-catenin signaling to polarize the termini of their anteroposterior axis, but little is known about how regeneration signaling restores regionalization along body or organ axes. We identify three genes expressed constitutively in overlapping body-wide transcriptional gradients that control trunk-tail positional identity in regeneration. ptk7 encodes a trunk-expressed kinase-dead Wnt co-receptor, wntP-2 encodes a posterior-expressed Wnt ligand, and ndl-3 encodes an anterior-expressed homolog of conserved FGFRL/nou-darake decoy receptors. ptk7 and wntP-2 maintain and allow appropriate regeneration of trunk tissue position independently of canonical Wnt signaling and with suppression of ndl-3 expression in the posterior. These results suggest that restoration of regional identity in regeneration involves the interpretation and re-establishment of axis-wide transcriptional gradients of signaling molecules.
authors.affiliation: Department of Molecular Biosciences, Northwestern University, Evanston, United States.
authors.forename: Rachel
authors.initials: R
authors.lastname: Lander
authors.affiliation: Department of Molecular Biosciences, Northwestern University, Evanston, United States.|Robert Lurie Comprehensive Cancer Center, Northwestern University, Evanston, United States.
authors.forename: Christian P
authors.identifier: 0000-0001-7552-6865
authors.initials: CP
authors.lastname: Petersen
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000235:genetics*; D002454:Cell Differentiation; D005786:Gene Expression Regulation; D015801:Helminth Proteins / Q000235:genetics* / Q000378:metabolism; D010932:Planarians / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics* / Q000378:metabolism; D060490:Receptors, Wnt / Q000235:genetics / Q000378:metabolism; D012038:Regeneration / Q000235:genetics; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D014158:Transcription, Genetic; D051153:Wnt Proteins / Q000235:genetics* / Q000378:metabolism; D060449:Wnt Signaling Pathway; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism
chemical_list: D015801:Helminth Proteins; D017468:Receptors, Fibroblast Growth Factor; D060490:Receptors, Wnt; D051153:Wnt Proteins; D051176:beta Catenin; D020794:Receptor Protein-Tyrosine Kinases
keywords: S. mediterranea; Wnt; axis; developmental biology; pattern control; planaria; regeneration; stem cells