Retroactive, a membrane-anchored extracellular protein related to vertebrate snake neurotoxin-like proteins, is required for cuticle organization in the larva of Drosophila melanogaster.
Mutations in the rtv gene cause disarrangement of chitin fibers in the cuticle of the Drosophila larva, and occasionally the cuticle detaches from the epidermis. We have identified the rtv gene, and using the new HHpred homology detection method, we show that the Rtv protein defines a new family of disulfide-rich proteins in insects that are related to vertebrate snake neurotoxin-like proteins, including CD59 and transforming growth factor-beta type II receptors. Rtv is an extracellular membrane-anchored protein exposing six aromatic residues that may mediate binding to chitin. We propose that this binding function of Rtv may assist the organization of chitin fibers at the epidermal cell surface during cuticle assembly.
Moussian
Bernard
B
Department of Genetics, Max-Planck Institute for Developmental Biology, Tübingen, Germany. bernard.moussian@tuebingen.mpg.de
Söding
Johannes
J
Schwarz
Heinz
H
Nüsslein-Volhard
Christiane
C
D000595:Amino Acid Sequence; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D004817:Epidermis / Q000196:embryology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006257:Head / Q000196:embryology; D034582:Integumentary System / Q000254:growth & development*; D007814:Larva / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009498:Neurotoxins / Q000737:chemistry*; D010641:Phenotype; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D012910:Snake Venoms / Q000737:chemistry*; D014132:Trachea / Q000196:embryology / Q000378:metabolism
D029721:Drosophila Proteins; D008565:Membrane Proteins; D009498:Neurotoxins; D012910:Snake Venoms; C504913:rtv protein, Drosophila