Drosophila adult muscle precursor cells contribute to motor axon pathfinding and proper innervation of embryonic muscles

Development. 2020 Feb 17;147(4):dev183004. doi: 10.1242/dev.183004.


Despites several decades of studies on the neuromuscular system, the relationship between muscle stem cells and motor neurons remains elusive. Using the Drosophila model, we provide evidence that adult muscle precursors (AMPs), the Drosophila muscle stem cells, interact with the motor axons during embryogenesis. AMPs not only hold the capacity to attract the navigating intersegmental (ISN) and segmental a (SNa) nerve branches, but are also mandatory to the innervation of muscles in the lateral field. This so-far-ignored AMP role involves their filopodia-based interactions with nerve growth cones. In parallel, we report the previously undetected expression of the guidance molecule-encoding genes sidestep and side IV in AMPs. Altogether, our data support the view that Drosophila muscle stem cells represent spatial landmarks for navigating motor neurons and reveal that their positioning is crucial for the muscles innervation in the lateral region. Furthermore, AMPs and motor axons are interdependent, as the genetic ablation of SNa leads to a specific loss of SNa-associated lateral AMPs.

Keywords: Adult muscle precursors (AMPs); Drosophila; Guidance; Motor axon; Side.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Axon Guidance
  • Axons / physiology*
  • Cell Movement
  • Drosophila Proteins / physiology
  • Drosophila melanogaster / embryology
  • Genotype
  • Green Fluorescent Proteins
  • Growth Cones / physiology
  • Immunohistochemistry
  • In Situ Hybridization
  • Membrane Proteins / physiology
  • Microscopy, Fluorescence
  • Motor Neurons / physiology*
  • Muscles / embryology*
  • Muscles / innervation*
  • Myoblasts / physiology*
  • Pseudopodia / physiology
  • Signal Transduction
  • Stem Cells / cytology


  • Drosophila Proteins
  • Membrane Proteins
  • side IV protein, Drosophila
  • side protein, Drosophila
  • Green Fluorescent Proteins