Purification and characterization of an insulin-related peptide in the desert locust, Schistocerca gregaria: immunolocalization, cDNA cloning, transcript profiling and interaction with neuroparsin.
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.
Badisco
Liesbeth
L
Department of Animal Physiology and Neurobiology, Zoological Institute K U Leuven, Naamsestraat 59, PO Box 02465, B-3000 Leuven, Belgium.
Claeys
Ilse
I
Van Hiel
Matthias
M
Clynen
Elke
E
Huybrechts
Jurgen
J
Vandersmissen
Tim
T
Van Soest
Sofie
S
Vanden Bosch
Luc
L
Simonet
Gert
G
Vanden Broeck
Jozef
J
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*
D018076:DNA, Complementary; D007301:Insect Hormones; D019476:Insect Proteins; D007328:Insulin; D009419:Nerve Tissue Proteins; D010455:Peptides