Identification of the vertebrate Iroquois homeobox gene family with overlapping expression during early development of the nervous system

Mech Dev. 1997 Dec;69(1-2):169-81. doi: 10.1016/s0925-4773(97)00165-2.


In Drosophila the decision processes between the neural and epidermal fate for equipotent ectodermal cells depend on the activity of proneural genes. Members of the Drosophila Iroquois-Complex (Iro-C) positively regulate the activity of certain proneural AS-C genes during the formation of external sensory organs. We have identified and characterized three mouse Iroquois-related genes: Irx1, -2 and -3, which have a homeodomain very similar to that of the Drosophila Iro-C genes. The sequence similarity implies that these three genes represent a separate homeobox family. All three genes are expressed with distinct spatio/temporal patterns during early mouse embryogenesis. These patterns implicate them in a number of embryonic developmental processes: the A/P and D/V patterning of specific regions of the central nervous system (CNS), and regionalization of the otic vesicle, branchial epithelium and limbs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Blotting, Northern
  • Conserved Sequence
  • Drosophila / embryology
  • Drosophila / genetics
  • Ear / embryology
  • Extremities / embryology
  • Gene Expression Regulation, Developmental*
  • Homeodomain Proteins / genetics*
  • In Situ Hybridization
  • Mice
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Nervous System / embryology*
  • Sequence Homology, Amino Acid
  • Tissue Distribution
  • Transcription Factors / genetics*
  • Transcription, Genetic
  • Vertebrates / genetics


  • Homeodomain Proteins
  • Irx1 protein, mouse
  • Transcription Factors

Associated data

  • GENBANK/Y15000
  • GENBANK/Y15001
  • GENBANK/Y15002