title: Cloning of the cDNA encoding Scg-SPRP, an unusual Ser-protease-related protein from vitellogenic female desert locusts (Schistocerca gregaria).
abstract: The cDNA coding for a Ser-protease-related protein (Scg-SPRP) was cloned from desert locust (Schistocerca gregaria) midgut. The derived amino acid sequence consists of 260 residues and shows strong sequence similarity to insect trypsin-like molecules. It is, however, likely that Scg-SPRP is not a proteolytically active enzyme and that it plays another physiologically relevant role, since two out of three residues which are indispensable for catalytic activity of Ser-proteases are replaced. Northern analysis revealed that the Scg-SPRP gene is expressed in midgut tissue and that this expression is strongly induced in adult female locusts. Moreover, the occurrence of the transcript (1.2 kb) fluctuates during the molting cycle and during the female reproductive cycle. Juvenile hormone (JH III) dependence of transcription was investigated by chemical allatectomy (precocene I) of adult females. This resulted in inhibition of vitellogenesis and in disappearance of the Scg-SPRP transcript. Expression of Scg-SPRP in precocene-treated locusts could be reinduced by additional treatment with JH III or with 20-OH-ecdysone.
authors.affiliation: Laboratory for Developmental Physiology and Molecular Biology, Zoological Institute K. U. Leuven, Leuven, Belgium.
authors.forename: S J
authors.initials: SJ
authors.lastname: Chiou
authors.forename: J
authors.initials: J
authors.lastname: Vanden Broeck
authors.forename: I
authors.initials: I
authors.lastname: Janssen
authors.forename: D
authors.initials: D
authors.lastname: Borovsky
authors.forename: F
authors.initials: F
authors.lastname: Vandenbussche
authors.forename: G
authors.initials: G
authors.lastname: Simonet
authors.forename: A
authors.initials: A
authors.lastname: De Loof
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001578:Benzopyrans / Q000494:pharmacology; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004064:Digestive System / Q000201:enzymology; D005260:Female; D006110:Grasshoppers / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D019476:Insect Proteins / Q000235:genetics*; D007605:Juvenile Hormones / Q000037:antagonists & inhibitors; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012098:Reproduction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000235:genetics*; D012717:Sesquiterpenes / Q000494:pharmacology; D014819:Vitellogenins / Q000096:biosynthesis*
chemical_list: D001578:Benzopyrans; D018076:DNA, Complementary; D019476:Insect Proteins; D007605:Juvenile Hormones; D012717:Sesquiterpenes; D014819:Vitellogenins; C019539:precocene I; C036585:juvenile hormone III; D012697:Serine Endopeptidases