title: BMP4-dependent expression of Xenopus Grainyhead-like 1 is essential for epidermal differentiation.
abstract: Morphogen-dependent epidermal-specific transacting factors have not been defined in vertebrates. We demonstrate that a member of the grainyhead transcription factor family, Grainyhead-like 1 (XGrhl1) is essential for ectodermal ontogeny in Xenopus laevis. Expression of this factor is restricted to epidermal cells. Moreover, XGrhl1 is regulated by the BMP4 signaling cascade. Disruption of XGrhl1 activity in vivo results in a severe defect in terminal epidermal differentiation, with inhibition of XK81A1 epidermal keratin gene expression, a key target of BMP4 signaling. Furthermore, transcription of the XK81A1 gene is modulated directly by binding of XGRHL1 to a promoter-localized binding motif that is essential for high-level expression. These results establish a novel developmental role for XGrhl1 as a crucial tissue-specific regulator of vertebrate epidermal differentiation.
authors.affiliation: Department of Hematology/Oncology, St Jude Children's Research Hospital, Memphis, TN 38105, USA.
authors.forename: Jianning
authors.initials: J
authors.lastname: Tao
authors.forename: Emin
authors.initials: E
authors.lastname: Kuliyev
authors.forename: Xi
authors.initials: X
authors.lastname: Wang
authors.forename: Xiuling
authors.initials: X
authors.lastname: Li
authors.forename: Tomasz
authors.initials: T
authors.lastname: Wilanowski
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Jane
authors.forename: Paul E
authors.initials: PE
authors.lastname: Mead
authors.forename: John M
authors.initials: JM
authors.lastname: Cunningham
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D001665:Binding Sites; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000378:metabolism*; D002454:Cell Differentiation; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D004475:Ectoderm / Q000378:metabolism; D004817:Epidermis / Q000196:embryology / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D005982:Glutathione Transferase / Q000378:metabolism; D007633:Keratins / Q000096:biosynthesis / Q000378:metabolism; D008156:Luciferases / Q000378:metabolism; D008954:Models, Biological; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D013997:Time Factors; D015533:Transcriptional Activation; D029867:Xenopus Proteins / Q000096:biosynthesis* / Q000502:physiology; D014982:Xenopus laevis / Q000196:embryology*
chemical_list: D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D017931:DNA Primers; C500131:GRHL1 protein, Xenopus; D029867:Xenopus Proteins; C525812:bmp4 protein, Xenopus; D007633:Keratins; D008156:Luciferases; D005982:Glutathione Transferase