Otx/otd homeobox genes specify distinct sensory neuron identities in C. elegans

Dev Cell. 2003 Oct;5(4):621-33. doi: 10.1016/s1534-5807(03)00293-4.


The mechanisms by which the diverse functional identities of neurons are generated are poorly understood. C. elegans responds to thermal and chemical stimuli using 12 types of sensory neurons. The Otx/otd homolog ttx-1 specifies the identities of the AFD thermosensory neurons. We show here that ceh-36 and ceh-37, the remaining two Otx-like genes in the C. elegans genome, specify the identities of AWC, ASE, and AWB chemosensory neurons, defining a role for this gene family in sensory neuron specification. All C. elegans Otx genes and rat Otx1 can substitute for ceh-37 and ceh-36, but only ceh-37 functionally substitutes for ttx-1. Functional substitution in the AWB neurons is mediated by activation of the same downstream target lim-4 by different Otx genes. Misexpression experiments indicate that although the specific identity adopted upon expression of an Otx gene may be constrained by the cellular context, individual Otx genes preferentially promote distinct neuronal identities.

Publication types

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

MeSH terms

  • Alleles
  • Animals
  • Animals, Genetically Modified
  • Behavior, Animal
  • Caenorhabditis elegans / genetics*
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism
  • Drosophila Proteins
  • Escape Reaction / drug effects
  • Gene Expression Regulation
  • Genes, Helminth
  • Genes, Homeobox / genetics
  • Genes, Homeobox / physiology*
  • Genetic Markers
  • Genetic Structures
  • Genotype
  • Helminth Proteins / chemistry
  • Helminth Proteins / genetics
  • Helminth Proteins / physiology
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / metabolism
  • Immunohistochemistry
  • Ketones / pharmacology
  • Molecular Sequence Data
  • Mutation
  • Neurons, Afferent / classification
  • Neurons, Afferent / drug effects
  • Neurons, Afferent / metabolism*
  • Neurons, Afferent / physiology
  • Odorants
  • Otx Transcription Factors
  • Sequence Alignment


  • CEH-37 protein, C elegans
  • Caenorhabditis elegans Proteins
  • Drosophila Proteins
  • Genetic Markers
  • Helminth Proteins
  • Homeodomain Proteins
  • Ketones
  • Otx Transcription Factors
  • oc protein, Drosophila
  • 2-nonanone