The Drosophila beaten path gene encodes a novel secreted protein that regulates defasciculation at motor axon choice points

Cell. 1996 Dec 13;87(6):1049-58. doi: 10.1016/s0092-8674(00)81799-7.

Abstract

In the Drosophila embryo, at specific choice points along the major motor nerves, subsets of motor axons defasciculate and then steer into their muscle target regions. Here we describe the analysis of beaten path (beat), a gene required for the selective defasciculation of motor axons at these choice points. In beat mutant embryos, motor axons fail to defasciculate and bypass their targets. This phenotype is suppressed by mutations in FasII and conn, two genes encoding cell adhesion molecules expressed on motor axons, suggesting that beat provides an antiadhesive function. beat encodes a novel secreted protein that is expressed by motoneurons during outgrowth. Rescue and ectopic expression experiments support the model that Beat protein is secreted by motor axons where it functions to regulate their selective defasciculation at specific choice points.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Axons / chemistry
  • Axons / metabolism
  • Axons / physiology*
  • Cell Adhesion / physiology
  • Cell Adhesion Molecules, Neuronal / genetics
  • Cell Adhesion Molecules, Neuronal / metabolism
  • Chromosome Mapping
  • Cloning, Molecular
  • Connectin
  • Drosophila / genetics*
  • Drosophila Proteins*
  • Gene Expression Regulation, Developmental / physiology
  • Genes, Insect / physiology
  • Membrane Proteins / genetics
  • Molecular Sequence Data
  • Motor Neurons / chemistry
  • Motor Neurons / physiology*
  • Motor Neurons / ultrastructure
  • Muscle Proteins / genetics
  • Muscle Proteins / metabolism
  • Muscles / chemistry
  • Muscles / innervation
  • Muscles / physiology
  • Mutagenesis / physiology
  • Nerve Tissue Proteins / genetics*
  • Nerve Tissue Proteins / metabolism
  • Neurites / chemistry
  • Neurites / metabolism
  • Neurites / physiology
  • Phenotype
  • Protein Kinases / genetics
  • Protein Kinases / metabolism
  • RNA, Messenger / metabolism

Substances

  • Cell Adhesion Molecules, Neuronal
  • Connectin
  • Drosophila Proteins
  • Membrane Proteins
  • Muscle Proteins
  • Nerve Tissue Proteins
  • RNA, Messenger
  • beat-Ia protein, Drosophila
  • fasciclin II
  • Protein Kinases