Components of wingless signalling in Drosophila.
The determination of specific cell fates and polarity within each segmental unit of the Drosophila embryo involves the products of the segment polarity genes. One of these, wingless (wg), encodes a secreted protein that is homologous to the mammalian proto-oncogene Wnt-1 (refs 4, 5). In the embryonic epidermis, wg is expressed in a single row of cells within each segmental unit, although its activity is required for the correct patterning of most of the epidermis. Initially Wg signals to adjacent posterior cells, maintaining engrailed (en) expression. Later during embryogenesis, wg specifies the differentiation of naked cuticle. Wg signalling functions by inactivating or antagonizing the activity of zestewhite 3 (zw3). We have investigated the requirement in the Wg signal transduction pathway for the three genes armadillo (arm), dishevelled (dsh) and porcupine (porc), all of which have embryonic mutant phenotypes similar to wg. Our results indicate that dsh and porc act upstream of zw3, and arm acts downstream of zw3.
Siegfried
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Department of Genetics, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115.
Wilder
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EL
Perrimon
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D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D051186:Armadillo Domain Proteins; D016764:Cell Polarity; D003433:Crosses, Genetic; D000072261:Dishevelled Proteins; D004330:Drosophila / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins; D005260:Female; D005786:Gene Expression Regulation; D005838:Genotype; D007301:Insect Hormones / Q000235:genetics / Q000378:metabolism; D007814:Larva; D008297:Male; D009154:Mutation; D010750:Phosphoproteins; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D015534:Trans-Activators; D014157:Transcription Factors; D051155:Wnt1 Protein
C495305:ARM protein, Drosophila; D048868:Adaptor Proteins, Signal Transducing; D051186:Armadillo Domain Proteins; D000072261:Dishevelled Proteins; D029721:Drosophila Proteins; D007301:Insect Hormones; D010750:Phosphoproteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D051155:Wnt1 Protein; C000606588:dsh protein, Drosophila; C074622:wg protein, Drosophila