Embryonic expression and characterization of a Ptx1 homolog in Drosophila

Mech Dev. 1997 Nov;68(1-2):139-47. doi: 10.1016/s0925-4773(97)00139-1.


We describe the molecular characterization of the paired-type homeobox gene D-Ptx1 of Drosophila, a close homolog of the mouse pituitary homeobox gene Ptx1 and the unc-30 gene of C. elegans, characterized by a lysine residue at position 9 of the third alpha-helix of the homeodomain. D-Ptx1 is expressed at various restricted locations throughout embryogenesis. Initial expression of D-Ptx1 in the posterior-most region of the blastoderm embryo is controlled by fork head activity in response to the activated Ras/Raf signaling pathway. During later stages of embryonic development. D-Ptx1 transcripts and protein accumulate in the posterior portion of the midgut, in the developing Malpighian tubules, in a subset of ventral somatic muscles, and in neural cells. Phenotypic analysis of gain-of-function and lack-of-function mutant embryos show that the D-Ptx1 gene is not involved in morphologically apparent differentiation processes. We conclude that D-Ptx1 is more likely to control physiological cell functions than pattern formation during Drosophila embryogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Animals, Genetically Modified
  • Blastoderm
  • Body Patterning / genetics
  • Drosophila / embryology*
  • Drosophila / genetics*
  • Drosophila Proteins*
  • Embryo, Nonmammalian
  • Forkhead Transcription Factors
  • Gene Expression Regulation, Developmental*
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / metabolism
  • Molecular Sequence Data
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Paired Box Transcription Factors
  • Phenotype
  • Sequence Homology, Amino Acid
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Transcription, Genetic


  • Drosophila Proteins
  • Forkhead Transcription Factors
  • Homeodomain Proteins
  • Nuclear Proteins
  • Paired Box Transcription Factors
  • Ptx1 protein, Drosophila
  • Transcription Factors
  • homeobox protein PITX1

Associated data

  • GENBANK/AJ001519