title: Purification and characterization of an insulin-related peptide in the desert locust, Schistocerca gregaria: immunolocalization, cDNA cloning, transcript profiling and interaction with neuroparsin.
abstract: Members of the insulin superfamily are not restricted to vertebrates, but have also been identified in invertebrate species. In the current report, we present the characterization of Scg-insulin-related peptide (IRP), an insulin-related peptide in the desert locust, Schistocerca gregaria. This peptide was isolated from corpora cardiaca (CC) extracts by means of a high-performance liquid chromatography (HPLC)-based purification strategy. Subsequent cloning and sequencing of the corresponding cDNA revealed that the encoded Scg-IRP precursor displays the structural organization that is typical for members of the insulin superfamily. Moreover, immunocytochemistry on brain tissue sections demonstrated the presence of Scg-IRP in median neurosecretory cells of the pars intercerebralis and their projections towards the storage part of the CC. Quantitative real-time RT-PCR studies revealed the presence of Scg-IRP transcripts in a variety of tissues, including nervous tissue and fat body. Furthermore, these transcripts showed a tissue- and phase-dependent, temporal regulation during the reproductive cycle of adult males and females. Finally, we demonstrated that Scg-IRP interacts in vitro with a recombinant neuroparsin, a locust protein displaying sequence similarity with vertebrate IGF binding proteins.
authors.affiliation: Department of Animal Physiology and Neurobiology, Zoological Institute K U Leuven, Naamsestraat 59, PO Box 02465, B-3000 Leuven, Belgium.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Badisco
authors.forename: Ilse
authors.initials: I
authors.lastname: Claeys
authors.forename: Matthias
authors.initials: M
authors.lastname: Van Hiel
authors.forename: Elke
authors.initials: E
authors.lastname: Clynen
authors.forename: Jurgen
authors.initials: J
authors.lastname: Huybrechts
authors.forename: Tim
authors.initials: T
authors.lastname: Vandersmissen
authors.forename: Sofie
authors.initials: S
authors.lastname: Van Soest
authors.forename: Luc
authors.initials: L
authors.lastname: Vanden Bosch
authors.forename: Gert
authors.initials: G
authors.lastname: Simonet
authors.forename: Jozef
authors.initials: J
authors.lastname: Vanden Broeck
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006110:Grasshoppers / Q000378:metabolism*; D007301:Insect Hormones / Q000235:genetics / Q000378:metabolism*; D019476:Insect Proteins / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity; D010455:Peptides / Q000235:genetics / Q000378:metabolism*
chemical_list: D018076:DNA, Complementary; D007301:Insect Hormones; D019476:Insect Proteins; D007328:Insulin; D009419:Nerve Tissue Proteins; D010455:Peptides