title: The two Xenopus Gbx2 genes exhibit similar, but not identical expression patterns and can affect head formation.
abstract: Gbx2 homeobox genes are important for formation and function of the midbrain/hindbrain boundary, namely the isthmic organizer. Two Gbx2 genes were identified in Xenopus laevis, differing in 13 amino acids, including a change in the homeodomain. Xgbx2a is activated earlier during gastrulation and reaches higher levels of expression while Xgbx2b is expressed later, at lower levels and has an additional domain in the ventral blood islands. Their overexpression results in microcephalic embryos with shortened axes and defects in brain and notochord formation. Both genes encode functionally homologous proteins, which differ primarily in their temporal and spatial expression patterns.
authors.affiliation: Department of Cellular Biochemistry and Human Genetics, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
authors.forename: E
authors.initials: E
authors.lastname: Tour
authors.forename: G
authors.initials: G
authors.lastname: Pillemer
authors.forename: Y
authors.initials: Y
authors.lastname: Gruenbaum
authors.forename: A
authors.initials: A
authors.lastname: Fainsod
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D015870:Gene Expression; D020869:Gene Expression Profiling; D006257:Head / Q000196:embryology*; D018398:Homeodomain Proteins / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D009024:Morphogenesis; D020033:Protein Isoforms / Q000235:genetics / Q000502:physiology; D029867:Xenopus Proteins; D014982:Xenopus laevis / Q000196:embryology / Q000235:genetics
chemical_list: C513180:Gbx2 protein, Xenopus; D018398:Homeodomain Proteins; D020033:Protein Isoforms; D029867:Xenopus Proteins