title: The sidekick gene, a member of the immunoglobulin superfamily, is required for pattern formation in the Drosophila eye.
abstract: In the Drosophila eye imaginal disc the photoreceptor cells (R cells) differentiate according to a precise spatial and temporal order. The sidekick (sdk) gene is necessary to prevent extra R cells from differentiating during eye disc development. The extra cell appears between R3 and R4 early in R cell clusters and is most likely the result of the mystery cell inappropriately differentiating as an R cell. Mosaic analysis shows that sdk is required neither in the R cells nor in the extra cell, suggesting that sdk is necessary in the surrounding undifferentiated cells. The sdk gene codes for a protein that is a member of the immunoglobulin superfamily, having six immunoglobulin domains, thirteen fibronectin repeats and a transmembrane domain. The protein structure is consistent with its participation in cell-cell interaction during eye development.
authors.affiliation: Albert Einstein College of Medicine, Department of Developmental and Molecular Biology, Bronx, NY 10461, USA.
authors.forename: D N
authors.initials: DN
authors.lastname: Nguyen
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.forename: M L
authors.initials: ML
authors.lastname: Litsky
authors.forename: R
authors.initials: R
authors.lastname: Reinke
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D029721:Drosophila Proteins; D005123:Eye / Q000254:growth & development* / Q000378:metabolism; D005124:Eye Abnormalities / Q000235:genetics / Q000473:pathology; D005136:Eye Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D017344:Genes, Insect; D007136:Immunoglobulins / Q000235:genetics; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D009154:Mutation; D019006:Neural Cell Adhesion Molecules; D010641:Phenotype; D010786:Photoreceptor Cells / Q000166:cytology / Q000254:growth & development / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D029721:Drosophila Proteins; D005136:Eye Proteins; D007136:Immunoglobulins; D019476:Insect Proteins; D008565:Membrane Proteins; D019006:Neural Cell Adhesion Molecules; C108528:sdk protein, Drosophila