Heatshock otd / OTX2

The homeobox genes of the orthodenticle (otd)/Otx family play conserved roles in embryogenesis of the head and brain. Gene replacement experiments show that the Drosophila otd gene and orthologous mammalian Otx genes are functionally equivalent, in that overexpression of either gene in null mutants of Drosophila or mouse can restore defects in cephalic and brain development. This suggests that otd and Otx genes can control a comparable subset of downstream target genes in either organism. Here we use quantitative transcript imaging to analyze this equivalence of Drosophila otd and human Otx gene action at a genomic level. In this study, transgenic fly strains carrying the otd coding sequence or the human Otx2 coding sequence under control of the heat inducible Hsp70 promoter were used [Leuzinger et al.: Equivalence of the fly orthodenticle gene and the human OTX genes in embryonic brain development of Drosophila. Development 1998; 125:1703-1710.]. Stage 10-17 embryos were given a 25-min heat pulse in order to overexpress the otd or Otx2 genes and allowed to recover for 25 min. Keywords = Drosophila melanogaster, embryo, brain, development, otd, OTX, heatshock Keywords: ordered