title: Gastrulation defective, a complement factor C2/B-like protease, interprets a ventral prepattern in Drosophila.
abstract: gastrulation defective (gd) encodes a serine protease required for specification of dorsal-ventral cell fates during Drosophila embryogenesis. Using RNA microinjection, I show that wild-type gd RNA can restore ventrolateral pattern elements with correct polarity with respect to egg shape in embryos lacking gd function. While low RNA concentrations restore ventrolateral pattern elements, higher concentrations ventralize the embryo. Gastrulation defective concentration has a rate-limiting effect on the domain of high Dorsal concentration but little effect upon the slope of the gradient. In embryos from pipe-null females, much higher RNA concentrations generate an ectopic axis oriented with respect to the site of injection. The data suggest that the Dorsal gradient is not directly determined by asymmetric cues in the eggshell but arises de novo within the perivitelline space as a consequence of self-regulatory properties of the protease cascade. A homology to the mammalian complement factors C2 and B is also described.
authors.affiliation: Genetics Department, University of Copenhagen, Øster Farimagsgade 2A, DK-1353 Copenhagen K, Denmark. rdelotto@biobase.dk
authors.forename: R
authors.initials: R
authors.lastname: DeLotto
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019521:Body Patterning / Q000502:physiology*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics; D005260:Female; D017403:In Situ Hybridization; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008845:Microinjections; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012313:RNA / Q000008:administration & dosage / Q000378:metabolism; D012697:Serine Endopeptidases / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015238:Sulfotransferases / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism; D051879:Twist-Related Protein 1
chemical_list: D029721:Drosophila Proteins; D019476:Insect Proteins; D008565:Membrane Proteins; D009687:Nuclear Proteins; C081481:Rho protein, Drosophila; C472498:Stet protein, Drosophila; D014157:Transcription Factors; D051879:Twist-Related Protein 1; D012313:RNA; D015238:Sulfotransferases; C115847:pip protein, Drosophila; D012697:Serine Endopeptidases; C440488:gd protein, Drosophila