rpm-1, a conserved neuronal gene that regulates targeting and synaptogenesis in C. elegans

Neuron. 2000 May;26(2):345-56. doi: 10.1016/s0896-6273(00)81168-x.


Little is known of mechanisms regulating presynaptic differentiation. We identified rpm-1 in a screen for mutants with defects in patterning of a presynaptic marker at certain interneuronal synapses. The predicted RPM-1 protein contains zinc binding, RCC1, and other conserved motifs. In rpm-1 mutants, mechanosensory neurons fail to accumulate tagged vesicles, retract synaptic branches, and ectopically extend axons. Some motor neurons branch and overgrow; others show altered synaptic organization. Expression of RPM-1 in the presynaptic mechanosensory neurons is sufficient to rescue phenotypes in these cells. Certain rpm-1 phenotypes are temperature sensitive, revealing that RPM-1 function can be bypassed by maintaining mutants at the permissive temperature at stages commensurate with synapse formation in wild-type animals. These results indicate that RPM-1 functions cell autonomously during synaptogenesis to regulate neuronal morphology.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / anatomy & histology
  • Caenorhabditis elegans / genetics*
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins*
  • Conserved Sequence / genetics
  • Gene Targeting*
  • Guanine Nucleotide Exchange Factors / genetics*
  • Guanine Nucleotide Exchange Factors / metabolism
  • Guanine Nucleotide Exchange Factors / physiology*
  • Mechanoreceptors / physiology
  • Molecular Sequence Data
  • Motor Neurons / ultrastructure
  • Mutation / physiology
  • Neurons / metabolism
  • Neurons / physiology*
  • Synapses / physiology*
  • Synapses / ultrastructure
  • Synaptic Vesicles / ultrastructure
  • Temperature


  • Caenorhabditis elegans Proteins
  • Guanine Nucleotide Exchange Factors
  • RPM-1 protein, C elegans

Associated data

  • GENBANK/AC024696
  • GENBANK/AC027664
  • GENBANK/AF257062
  • GENBANK/U53146