Disease relevance of ect

• (1) Notch lethals, Five Notch mutants were studied which have been reported to give similar abnormalities in whole embryos: the nervous system displays a three-fold hypertrophy as part of a shift in the pattern of differentiation within ectodermal derivatives, and mesodermal derivatives do not differentiate [1].

High impact information on ect

• Expression of crumbs confers apical character on plasma membrane domains of ectodermal epithelia of Drosophila [2].
• Our results suggest that crumbs plays a key role in specifying the apical plasma membrane domain of ectodermal epithelial cells of Drosophila [2].
• We infer that dpp acts as an extracellular morphogen and that the graded activity of dpp specifies the pattern of ectodermal cell fates in the Drosophila embryo [3].
• Local function of the Notch gene for embryonic ectodermal pathway choice in Drosophila [4].
• Inhibition of NF-kappaB activity results in disruption of the apical ectodermal ridge and aberrant limb morphogenesis [5].

Biological context of ect

• The ect gene is temporally regulated during Drosophila development, with a major peak of expression during the second half of Drosophila embryogenesis [6].
• The Drosophila gene ectodermal (ect, located at 67D8-10 on chromosome 3) is expressed for a short period at mid-embryogenesis in all ectodermally derived tissues except the nervous system [7].
• The predicted gene product is implicated in a cell interaction mechanism required to achieve this ectodermal differentiation [8].
• When ectopically expressed, Xpbx1b can synergize with Xmeis1b to promote posterior neural and neural crest gene expression in ectodermal explants [9].
• The cell-lineage analysis of COPs using the yeast flpase (flp/FRT) method indicated that each of the eight COPs originated from an individual undifferentiated ectodermal cell [10].

Anatomical context of ect

• Induction of visceral and cardiac mesoderm by ectodermal Dpp in the early Drosophila embryo [11].
• Expression of Radical fringe in limb-bud ectoderm regulates apical ectodermal ridge formation [12].
• The apical ectodermal ridge of the vertebrate limb bud lies at the junction of the dorsal and ventral ectoderm and directs patterning of the growing limb [12].
• In situ hybridization analysis of mouse embryos shows that the Hox-2.6 is expressed in ectodermal derivatives: spinal cord, hindbrain, dorsal root ganglia, and the Xth cranial ganglia [13].
• Dorsal-ventral patterning within the ectodermal and mesodermal germ layers of Drosophila and Xenopus embryos is specified by a system of genes that has been conserved over 500 million years of evolution [14].

Associations of ect with chemical compounds

• Both ectodermal and mesenchymal expression in limb bud were rapidly suppressed by local treatment of retinoic acid which can generate mirror-image duplication of digits [15].
• Gastrulae genetically depleted of serotonin or the 5-ht(2Dro) receptor do not extend their germband properly, and the ectodermal movements becomes asynchronous with the morphogenetic movements in the endoderm and mesoderm [16].
• Mucin GPs carrying Gal(beta 1,3)GalNAc disaccharide recognized by the MAbs were immunochemically localized in several Drosophila tissues of ectodermal, mesodermal and germ line origin, including epidermal and follicle cells capable of their secretion [17].

Regulatory relationships of ect

• Given the similarities between JING and the vertebrate CCAAT-binding protein AEBP2, we propose that jing regulates transcriptional mechanisms in Drosophila embryos and promotes cellular differentiation in ectodermal derivatives [18].
• In wild-type embryos, Tollo/Toll-8 is expressed by ectodermal cells that surround differentiating neurons and precedes HRP-epitope appearance [19].
• In Xenopus the activins and Vg1 are potent dorsal mesoderm inducers while members of the bone morphogenetic protein (BMP) subclass pattern ventral mesoderm and regulate ectodermal cell fates [20].
• Both the mesodermal and ectodermal defects are reminiscent of those induced by altered forms of Drac1 and suggest that mbc may function in the same pathway [21].
• The results suggest that sr activity induces a subset of ectodermal cells to develop into muscle attachment sites and to provide spatial cues necessary to orient myotubes along the basal surface of the epidermis to their targeted attachment cells [22].

Other interactions of ect

• The principal homology between ect and MuIFN alpha 2 involves A + T-rich sequences with short repeats, which are located within the untranslated 3' end of the transcribed region of each gene [6].
• Coexpression of Tsg with chordin leads to a more efficient inhibition of the BMP activity in ectodermal explants [23].
• However, following gastrulation and germ band extension, Ubx transcripts accumulate in most of the ectodermal and mesodermal derivatives of the body, including those of all 14 parasegments [24].
• We establish that the jing zinc-finger transcription factor plays an essential role in controlling CNS midline and tracheal cell differentiation. jing transcripts and protein accumulate from stage 9 in the CNS midline, trachea and in segmental ectodermal stripes [18].
• Within the ectodermal layer, its level is neither elevated (as in the case of AS-C genes) nor reduced (as in the case of emc product) in the proneural cluster [25].

Analytical, diagnostic and therapeutic context of ect

• The antibody staining pattern of the ect protein corresponds to the in situ hybridization pattern of the transcript [7].
• In order to verify the occurrence of regulatory signals and to test the neurogenic capabilities of cells from various regions of the ectoderm, we have carried out homotopic and heterotopic transplantations of single ectodermal cells [26].
• Complementation tests show that the gene is required not only for oogenesis and embryogenesis, but also for pupal viability, for the growth of certain imaginal discs and for the patterning of specific ectodermal derivatives of the imaginal discs [27].
• Apical ectodermal ridge induction by the transplantation of En-1-overexpressing ectoderm in chick limb bud [28].

References