Twist1 has been demonstrated to play critical roles in the early development of neural crest and mesodermally derived tissues including the limb. Twist2 has been less well characterised but its relatively late onset of expression suggests specific roles in the development of a number of organs. Expression of Twist2 within the developing limbs begins after formation of the limb bud and persists within the peripheral mesenchyme until digital rays condense.
View Article and Find Full Text PDFChemokines are small secreted signalling molecules best known for their roles as chemoattractants for cells of the immune system. CXCL12 and its receptor CXCR4 comprise one chemokine signalling pathway with essential functions in non-immune cell types during embryonic development. CXCL14, a chemokine-encoding gene related to CXCL12, is developmentally regulated in zebrafish and Xenopus embryos, but its role during embryogenesis remains unknown.
View Article and Find Full Text PDFDlx homeodomain transcription factors are expressed in neural crest-derived mesenchyme of the pharyngeal arches and are required for patterning of the craniofacial skeleton. However, the cellular and molecular mechanisms by which Dlx factors control skeletogenesis in the facial primordia are unclear. We have investigated the function of Dlx2 and Dlx5 by sustained misexpression in ovo.
View Article and Find Full Text PDFMidbrain, hindbrain and vagal neural crest (NC) produced abundant enteric nervous system (ENS) in co-grafted aneural hindgut and midgut, using chick-quail chorio-allantoic membrane grafts, forming complete myenteric and submucosal plexuses. This ability dropped suddenly in cervical and thoracic NC levels, furnishing an incomplete ENS in one or both plexuses. Typically, one plexus was favoured over the other.
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