Cloning and Expression of Three Zebrafish Roundabout Homologs Suggest Roles in Axon Guidance and Cell Migration

Dev Dyn. 2001 Jun;221(2):216-30. doi: 10.1002/dvdy.1136.


We report the cloning and expression patterns of three novel zebrafish Roundabout homologs. The Roundabout (robo) gene encodes a transmembrane receptor that is essential for axon guidance in Drosophila and Robo family members have been implicated in cell migration. Analysis of extracellular domains and conserved cytoplasmic motifs shows that zebrafish Robo1 and Robo2 are orthologs of mammalian Robo1 and Robo2, respectively, while zebrafish Robo3 is likely to be an ortholog of mouse Rig-1. The three zebrafish robos are expressed in distinct but overlapping patterns during embryogenesis. They are highly expressed in the developing nervous system, including the olfactory system, visual system, hindbrain, cranial ganglia, spinal cord, and posterior lateral line primordium. They are also expressed in several nonneuronal tissues, including somites and fin buds. The timing and patterns of expression suggest roles for zebrafish robos in axon guidance and cell migration. Wiley-Liss, Inc.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Axons / metabolism*
  • Axons / physiology*
  • Cell Membrane / metabolism
  • Cell Movement
  • Cloning, Molecular
  • Cytoplasm / metabolism
  • DNA, Complementary / metabolism
  • Drosophila
  • Eye / embryology
  • Ganglia / embryology
  • Gene Expression Regulation, Developmental*
  • In Situ Hybridization
  • Models, Genetic
  • Molecular Sequence Data
  • Nerve Tissue Proteins
  • Protein Structure, Tertiary
  • Receptors, Immunologic / biosynthesis*
  • Receptors, Immunologic / genetics*
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • Spinal Cord / embryology
  • Time Factors
  • Tissue Distribution
  • Zebrafish


  • DNA, Complementary
  • Nerve Tissue Proteins
  • Receptors, Immunologic
  • roundabout protein