title: Sox5 Is a DNA-binding cofactor for BMP R-Smads that directs target specificity during patterning of the early ectoderm.
abstract: The SoxD factor, Sox5, is expressed in ectodermal cells at times and places where BMP signaling is active, including the cells of the animal hemisphere at blastula stages and the neural plate border and neural crest at neurula stages. Sox5 is required for proper ectoderm development, and deficient embryos display patterning defects characteristic of perturbations of BMP signaling, including loss of neural crest and epidermis and expansion of the neural plate. We show that Sox5 is essential for activation of BMP target genes in embryos and explants, that it physically interacts with BMP R-Smads, and that it is essential for recruitment of Smad1/4 to BMP regulatory elements. Our findings identify Sox5 as the long-sought DNA-binding partner for BMP R-Smads essential to plasticity and pattern in the early ectoderm.
authors.affiliation: Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Kara
authors.initials: K
authors.lastname: Nordin
authors.affiliation: Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Evanston, IL 60208, USA. Electronic address: clabonne@northwestern.edu.
authors.forename: Carole
authors.initials: C
authors.lastname: LaBonne
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000235:genetics / Q000502:physiology*; D052004:Bone Morphogenetic Protein Receptors / Q000378:metabolism*; D004247:DNA / Q000235:genetics; D004475:Ectoderm / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D009432:Neural Crest / Q000166:cytology; D054258:Neural Plate / Q000166:cytology; D055755:SOXD Transcription Factors / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D051785:Smad Proteins / Q000378:metabolism*; D014981:Xenopus / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029867:Xenopus Proteins / Q000378:metabolism*
chemical_list: D055755:SOXD Transcription Factors; D051785:Smad Proteins; C490302:Sox5 protein, Xenopus; D029867:Xenopus Proteins; D004247:DNA; D052004:Bone Morphogenetic Protein Receptors