title: Expression of truncated Sek-1 receptor tyrosine kinase disrupts the segmental restriction of gene expression in the Xenopus and zebrafish hindbrain.
abstract: During development of the vertebrate hindbrain regulatory gene expression is confined to precise segmental domains. Studies of cell lineage and gene expression suggest that establishment of these domains may involve a dynamic regulation of cell identity and restriction of cell movement between segments. We have taken a dominant negative approach to interfere with the function of Sek-1, a member of the Eph-related receptor tyrosine kinase family expressed in rhombomeres r3 and r5. In Xenopus and zebrafish embryos expressing truncated Sek-1, lacking kinase sequences, expression of r3/r5 markers occurs in adjacent even-numbered rhombomeres, in domains contiguous with r3 or r5. This disruption is rescued by full-length Sek-1, indicating a requirement for the kinase domain in the segmental restriction of gene expression. These data suggest that Sek-1, perhaps with other Eph-related receptors, is required for interactions that regulate the segmental identity or movement of cells.
authors.affiliation: Developmental Biology Research Centre, Randall Institute, Kings College, London, UK.
authors.forename: Q
authors.initials: Q
authors.lastname: Xu
authors.forename: G
authors.initials: G
authors.lastname: Alldus
authors.forename: N
authors.initials: N
authors.lastname: Holder
authors.forename: D G
authors.initials: DG
authors.lastname: Wilkinson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002450:Cell Communication; D003001:Cloning, Molecular; D004627:Embryonic Induction; D005326:Fetal Proteins / Q000235:genetics*; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D036122:Receptor, EphA4; D012249:Rhombencephalon / Q000196:embryology*; D014981:Xenopus / Q000196:embryology* / Q000235:genetics; D015027:Zebrafish / Q000196:embryology / Q000235:genetics
chemical_list: D005326:Fetal Proteins; D009419:Nerve Tissue Proteins; D020794:Receptor Protein-Tyrosine Kinases; D036122:Receptor, EphA4