title: The extracellular matrix molecule tenascin C modulates expression levels and territories of key patterning genes during spinal cord astrocyte specification.
abstract: The generation of astrocytes during the development of the mammalian spinal cord is poorly understood. Here, we demonstrate for the first time that the extracellular matrix glycoprotein tenascin C regulates the expression of key patterning genes during late embryonic spinal cord development, leading to a timely maturation of gliogenic neural precursor cells. We first show that tenascin C is expressed by gliogenic neural precursor cells during late embryonic development. The loss of tenascin C leads to a sustained generation and delayed migration of Fgfr3-expressing immature astrocytes in vivo. Consistent with an increased generation of astroglial cells, we documented an increased number of GFAP-positive astrocytes at later stages. Mechanistically, we could demonstrate an upregulation and domain shift of the patterning genes Nkx6.1 and Nkx2.2 in vivo. In addition, sulfatase 1, a known downstream target of Nkx2.2 in the ventral spinal cord, was also upregulated. Sulfatase 1 regulates growth factor signalling by cleaving sulphate residues from heparan sulphate proteoglycans. Consistent with this function, we observed changes in both FGF2 and EGF responsiveness of spinal cord neural precursor cells. Taken together, our data implicate Tnc in the regulation of proliferation and lineage progression of astroglial progenitors in specific domains of the developing spinal cord.
authors: Department for Cell Morphology and Molecular Neurobiology, Ruhr-University Bochum, Universitätsstrasse 150, Bochum, Germany.
authors: Michael
authors: M
authors: Karus
authors: Bernd
authors: B
authors: Denecke
authors: Charles
authors: C
authors: ffrench-Constant
authors: Stefan
authors: S
authors: Wiese
authors: Andreas
authors: A
authors: Faissner
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology*; D019521:Body Patterning / Q000235:genetics*; D002465:Cell Movement; D002478:Cells, Cultured; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D019812:Heparan Sulfate Proteoglycans / Q000378:metabolism; D000090322:Homeobox Protein Nkx-2.2; D018398:Homeodomain Proteins / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D058953:Neural Stem Cells / Q000378:metabolism; D055495:Neurogenesis / Q000235:genetics*; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000378:metabolism; D013116:Spinal Cord / Q000254:growth & development*; D015238:Sulfotransferases / Q000378:metabolism; D019063:Tenascin / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D015854:Up-Regulation; D029961:Zebrafish Proteins
chemical_list: D019812:Heparan Sulfate Proteoglycans; D000090322:Homeobox Protein Nkx-2.2; D018398:Homeodomain Proteins; C000715627:Nkx2-2 protein, mouse; C491328:Nkx6-1 protein, mouse; D019063:Tenascin; D014157:Transcription Factors; D029961:Zebrafish Proteins; C000715630:nkx2.2b protein, zebrafish; D016222:Fibroblast Growth Factor 2; C496366:Fgfr3 protein, mouse; D051498:Receptor, Fibroblast Growth Factor, Type 3; C486773:Sulf1 protein, mouse; D015238:Sulfotransferases