Specification of motor neuron identity by the MNR2 homeodomain protein

Cell. 1998 Oct 2;95(1):67-80. doi: 10.1016/s0092-8674(00)81783-3.


Sonic hedgehog signaling controls the differentiation of motor neurons in the ventral neural tube, but the intervening steps are poorly understood. A differential screen of a cDNA library derived from a single Shh-induced motor neuron has identified a novel homeobox gene, MNR2, expressed by motor neuron progenitors and transiently by postmitotic motor neurons. The ectopic expression of MNR2 in neural cells initiates a program of somatic motor neuron differentiation characterized by the expression of homeodomain proteins, by neurotransmitter phenotype, and by axonal trajectory. Our results suggest that the Shh-mediated induction of a single transcription factor, MNR2, is sufficient to direct somatic motor neuron differentiation.

Publication types

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

MeSH terms

  • Animals
  • Cell Differentiation
  • Chick Embryo
  • Gene Expression Regulation
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • Homeostasis
  • Motor Neurons / cytology*
  • Motor Neurons / metabolism
  • Muscle Proteins / genetics
  • Nerve Tissue Proteins / genetics
  • PAX7 Transcription Factor
  • Stem Cells
  • Transcription Factors / genetics


  • Homeodomain Proteins
  • MNR2 protein, vertebrate
  • Muscle Proteins
  • Nerve Tissue Proteins
  • PAX7 Transcription Factor
  • Transcription Factors

Associated data

  • GENBANK/AF066860
  • GENBANK/AF066861