Plexin-induced collapse assay in COS cells

Methods Enzymol. 2006;406:665-76. doi: 10.1016/S0076-6879(06)06052-6.


Semaphorins are a family of growth cone guidance molecules. When associated with their receptors and coreceptors, plexins and neuropilins, they act as chemorepellents for an extensive range of neuronal populations. The prototypic semaphorin, Sema3A, has a potent inhibitory effect on sensory axons emanating from dorsal root ganglia. This has formed the basis of the most famous assay for semaphorin activity, the chick dorsal root ganglia collapse assay. Recently, a heterologous, highly tractable assay has been used to investigate semaphorin signaling. In this system, the binding of recombinant semaphorins to COS cells expressing plexins and neuropilins induces a morphological collapse that may correlate with growth cone collapse. This chapter describes the optimization of this assay and outlines the subtle differences required to enable Sema3A-Fc and Sema4D-Fc to induce identical collapse phenotypes in COS cells expressing Plexin-A1 and neuropilin-1, or Plexin-B1, respectively.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, CD / biosynthesis
  • COS Cells / drug effects
  • COS Cells / ultrastructure
  • Cell Adhesion Molecules / pharmacology*
  • Chlorocebus aethiops
  • Cytoskeleton / drug effects
  • Humans
  • Nerve Tissue Proteins / metabolism
  • Nerve Tissue Proteins / pharmacology*
  • Neuropilin-1 / physiology
  • Receptors, Cell Surface / metabolism
  • Semaphorin-3A / biosynthesis
  • Semaphorins / biosynthesis


  • Antigens, CD
  • CD100 antigen
  • Cell Adhesion Molecules
  • Nerve Tissue Proteins
  • PLXNA1 protein, human
  • PLXNB1 protein, human
  • Receptors, Cell Surface
  • Semaphorin-3A
  • Semaphorins
  • plexin
  • Neuropilin-1