The role of hemocytes, serine protease inhibitors and pathogen-associated patterns in prophenoloxidase activation in the desert locust, Schistocerca gregaria.
The prophenoloxidase-activating system is an important component of the innate immune response of insects, involved in wound healing and melanotic encapsulation. In this paper we show that in the desert locust, Schistocerca gregaria, hemocytes, challenged with microbial elicitors, are indispensable for the limited proteolytic activation of prophenoloxidase (proPO) in plasma. In addition, we assessed the influence of serine protease inhibitors on the induction of PO-activity in plasma. While soybean Bowman-Birk inhibitor (SBBI) inhibited the PO activation by laminarin-treated hemocytes, the endogenous pacifastin-related inhibitors, SGPI-1 (S. gregaria pacifastin-related inhibitor-1) and SGPI-2 did not affect the PO-activity under similar conditions. On the other hand, real-time PCR analysis revealed that the transcripts, encoding SGPI-1-3, were more abundant in the fat body of immune challenged animals, as compared to control animals.
Franssens
Vanessa
V
Laboratory of Developmental Physiology, Genomics and Proteomics, Department of Animal Physiology and Neurobiology, Zoological Institute, K.U. Leuven, Naamsestraat 59, B-3000 Leuven, Belgium.
Simonet
Gert
G
Breugelmans
Bert
B
Van Soest
Sofie
S
Van Hoef
Vincent
V
Vanden Broeck
Jozef
J
D000818:Animals; D004156:Catechol Oxidase / Q000097:blood / Q000378:metabolism*; D002918:Chymotrypsin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D004792:Enzyme Precursors / Q000097:blood / Q000378:metabolism*; D005216:Fat Body / Q000187:drug effects / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D005936:Glucans; D006110:Grasshoppers / Q000201:enzymology* / Q000382:microbiology; D006434:Hemocytes / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D006458:Hemolymph / Q000378:metabolism; D054884:Host-Pathogen Interactions; D006801:Humans; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008954:Models, Biological; D010455:Peptides / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D011134:Polysaccharides / Q000494:pharmacology; D015842:Serine Proteinase Inhibitors / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D014358:Trypsin Inhibitor, Bowman-Birk Soybean / Q000494:pharmacology; D014361:Trypsin Inhibitors / Q000494:pharmacology
D004156:Catechol Oxidase; D002918:Chymotrypsin; D004792:Enzyme Precursors; D005936:Glucans; D019476:Insect Proteins; D008070:Lipopolysaccharides; D010455:Peptides; D011134:Polysaccharides; D015842:Serine Proteinase Inhibitors; D014358:Trypsin Inhibitor, Bowman-Birk Soybean; D014361:Trypsin Inhibitors; C113210:LOC126284306 protein, Schistocerca gregaria; C008247:laminaran; C038451:pro-phenoloxidase