title: Robo2-Slit1 dependent cell-cell interactions mediate assembly of the trigeminal ganglion.
abstract: Vertebrate cranial sensory ganglia, responsible for sensation of touch, taste and pain in the face and viscera, are composed of both ectodermal placode and neural crest cells. The cellular and molecular interactions allowing generation of complex ganglia remain unknown. Here, we show that proper formation of the trigeminal ganglion, the largest of the cranial ganglia, relies on reciprocal interactions between placode and neural crest cells in chick, as removal of either population resulted in severe defects. We demonstrate that ingressing placode cells express the Robo2 receptor and early migrating cranial neural crest cells express its cognate ligand Slit1. Perturbation of this receptor-ligand interaction by blocking Robo2 function or depleting either Robo2 or Slit1 using RNA interference disrupted proper ganglion formation. The resultant disorganization mimics the effects of neural crest ablation. Thus, our data reveal a novel and essential role for Robo2-Slit1 signaling in mediating neural crest-placode interactions during trigeminal gangliogenesis.
authors.affiliation: Division of Biology 139-74, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: Celia E
authors.initials: CE
authors.lastname: Shiau
authors.forename: Peter Y
authors.initials: PY
authors.lastname: Lwigale
authors.forename: Raman M
authors.initials: RM
authors.lastname: Das
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Wilson
authors.forename: Marianne
authors.initials: M
authors.lastname: Bronner-Fraser
mesh_terms: D000818:Animals; D002450:Cell Communication / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D002465:Cell Movement / Q000235:genetics*; D002642:Chick Embryo; D002645:Chickens; D003370:Coturnix; D015536:Down-Regulation / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009432:Neural Crest / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D034622:RNA Interference; D011971:Receptors, Immunologic / Q000235:genetics / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D012668:Trigeminal Ganglion / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D000097905:Roundabout Proteins
chemical_list: D029721:Drosophila Proteins; D006023:Glycoproteins; D009419:Nerve Tissue Proteins; D011971:Receptors, Immunologic; D000097905:Roundabout Proteins; C421243:Robo2 protein, Drosophila; C120566:slit protein, vertebrate