High impact information on ogre

• The Drosophila melanogaster genes Passover and l(1)ogre and the Caenorhabditis elegans gene unc-7 define a gene family whose function is not known [1].
• We propose that Zpg-containing gap junctional hemichannels in the germ cell plasma membrane may connect with hemichannels made of other innexin isoforms on adjacent somatic cells [2].
• The molecular composition of innexin-containing gap junctions and the functional significance of innexin oligomerization for development are largely unknown [3].
• Examination of transcriptional pattern indicates that l(1)ogre is expressed in derivatives of the ectoderm, endoderm, and mesoderm (but not in the germ line) in two developmental contexts: (i) during and shortly after the proliferative phase and (ii) during histolysis of some larval tissues [4].
• Specificity of gene action during central nervous system development in Drosophila melanogaster: analysis of the lethal (1) optic ganglion reduced locus [5].

Biological context of ogre

• However, parts of the expression patterns overlap, especially for prp33 and ogre which may be expressed from the same transcriptional enhancers [6].
• The cDNA contains an open reading frame with extensive homology to another D. melanogaster gene, l(1)ogre [7].
• Few data exist about the developmental role of the eight innexin genes which have been found in the Drosophila genome [8].
• Immunohistochemical analysis using cell polarity markers indicates that Innexin 1 is predominantly localized to the baso-lateral domain of epithelial cells, basal to septate junctions [9].
• These results show that the time of l(1)ogre+ gene action overlaps the period during which growth and assembly of the imaginal CNS occurs and are consistent with the hypothesis that l(1)ogre may act specifically in the imaginal CNS during its morphogenesis [5].

Anatomical context of ogre

• Flies with mutations in the gap junction genes (innexins), shakingB, and ogre have normal photoreceptor potentials but a defective response of the postsynaptic cells in the optic lamina [10].
• The Innexin gene family forms gap junctions in invertebrates [6].
• Our findings suggest that the distribution of Innexin channel proteins to specific membrane domains of epithelial cells is regulated by tissue specific factors during the development of epithelia in the fly embryo [9].
• Previous genetic studies have shown that wild-type function of the l(1)ogre (lethal (1) optic ganglion reduced) locus is essential for the generation and/or maintenance of the postembryonic neuroblasts including those from which the optic lobe is descended [11].

Other interactions of ogre

• Each chimera rescued either shakB or ogre but never both [12].

Analytical, diagnostic and therapeutic context of ogre

• In situ hybridization experiments have shown that most of the eight known innexin genes in Drosophila are expressed in a complex and overlapping temporal and spatial profile, with several members showing high levels of expression in developing epithelia of the embryo [9].
• Molecular cloning and analysis of l(1)ogre, a locus of Drosophila melanogaster with prominent effects on the postembryonic development of the central nervous system [11].

References