title: Homeotic transformation of rhombomere identity after localized Hoxb1 misexpression.
abstract: Segmentation of the hindbrain and branchial region is a conserved feature of head development, involving the nested expression of Hox genes. Although it is presumed that vertebrate Hox genes function as segment identifiers, responsible for mediating registration between elements of diverse embryonic origin, this assumption has remained untested. To assess this, retroviral misexpression was combined with orthotopic grafting in chick embryos to generate a mismatch in Hox coding between a specific rhombomere and its corresponding branchial arch. Rhombomere-restricted misexpression of a single gene, Hoxb1, resulted in the homeotic transformation of the rhombomere, revealed by reorganization of motor axon projections.
authors.affiliation: Department of Developmental Neurobiology, King's College London, Guy's Hospital, London SE1 9RT, UK.
authors.forename: E
authors.initials: E
authors.lastname: Bell
authors.forename: R J
authors.initials: RJ
authors.lastname: Wingate
authors.forename: A
authors.initials: A
authors.lastname: Lumsden
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology; D001934:Branchial Region / Q000196:embryology* / Q000294:innervation / Q000378:metabolism; D002454:Cell Differentiation; D002465:Cell Movement; D002642:Chick Embryo; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics; D050989:GATA2 Transcription Factor; D018507:Gene Expression Regulation, Developmental; D005801:Genes, Homeobox; D005822:Genetic Vectors; D018398:Homeodomain Proteins / Q000235:genetics* / Q000502:physiology; D008562:Membrane Glycoproteins / Q000235:genetics; D009046:Motor Neurons / Q000166:cytology / Q000502:physiology; D012249:Rhombencephalon / Q000196:embryology* / Q000378:metabolism / Q000637:transplantation; D014157:Transcription Factors / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D050989:GATA2 Transcription Factor; C101121:HOXB1 homeodomain protein; D018398:Homeodomain Proteins; D008562:Membrane Glycoproteins; D014157:Transcription Factors