title: Fibroblast growth factor receptor-3 regulates Paneth cell lineage allocation and accrual of epithelial stem cells during murine intestinal development.
abstract: Fibroblast growth factor receptor 3 (FGFR-3) is expressed in the lower crypt epithelium, where stem cells of the intestine reside. The role of FGFR-3 signaling in regulating features of intestinal morphogenesis was examined in FGFR-3-null (FGFR-3(-/-)) mice. FGFR-3(-/-) mice had only about half the number of intestinal crypts and a marked decrease in the number of functional clonogenic stem cells, as assessed by an in vivo microcolony-forming assay, compared with wild-type littermates. A marked deficit in allocation of progenitor cells to Paneth cell differentiation was noted, although all the principal epithelial lineages were represented in FGFR-3(-/-) mice. The total cellular content and nuclear localization of beta-catenin protein were reduced in FGFR-3(-/-) mice, as was expression of cyclin D1 and matrix metalloproteinase-7, major downstream targets of beta-catenin/T cell factor-4 (Tcf-4) signaling. Activation of FGFR-3 in Caco-2 cells, an intestinal epithelial cell line, abrogated the fall in beta-catenin/Tcf-4 signaling activity that is normally observed in these cells as cultures become progressively more confluent. These findings are consistent with the hypothesis that, during intestinal development, FGFR-3 signaling regulates crypt epithelial stem cell expansion and crypt morphogenesis, as well as Paneth cell lineage specification, through beta-catenin/Tcf-4-dependent and -independent pathways.
authors.affiliation: Digestive Health Center of Excellence, University of Virginia Health System, Charlottesville, VA 22908, USA.
authors.forename: Alda
authors.initials: A
authors.lastname: Vidrich
authors.forename: Jenny M
authors.initials: JM
authors.lastname: Buzan
authors.forename: Brooks
authors.initials: B
authors.lastname: Brodrick
authors.forename: Chibuzo
authors.initials: C
authors.lastname: Ilo
authors.forename: Leigh
authors.initials: L
authors.lastname: Bradley
authors.forename: Kirstin Skaar
authors.initials: KS
authors.lastname: Fendig
authors.forename: Thomas
authors.initials: T
authors.lastname: Sturgill
authors.forename: Steven M
authors.initials: SM
authors.lastname: Cohn
mesh_terms: D000367:Age Factors; D000375:Aging / Q000378:metabolism; D000818:Animals; D018938:Caco-2 Cells; D002454:Cell Differentiation; D019070:Cell Lineage; D002465:Cell Movement; D049109:Cell Proliferation; D019938:Cyclin D1 / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000254:growth & development; D020783:Matrix Metalloproteinase 7 / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D019879:Paneth Cells / Q000378:metabolism*; D010641:Phenotype; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013234:Stem Cells / Q000378:metabolism*; D051820:TCF Transcription Factors / Q000378:metabolism; D058118:Transcription Factor 7-Like 2 Protein; D051176:beta Catenin / Q000378:metabolism
chemical_list: C495270:CTNNB1 protein, human; C495267:CTNNB1 protein, mouse; C530105:Ccnd1 protein, mouse; D051820:TCF Transcription Factors; C544894:TCF7L2 protein, human; C544895:Tcf7l2 protein, mouse; D058118:Transcription Factor 7-Like 2 Protein; D051176:beta Catenin; D019938:Cyclin D1; C496365:FGFR3 protein, human; C496366:Fgfr3 protein, mouse; D051498:Receptor, Fibroblast Growth Factor, Type 3; D020783:Matrix Metalloproteinase 7