Analysis of an insect neuropeptide,Schistocerca gregaria ion transport peptide (ITP), expressed in insect cell systems

Autor: J. Meredith, Y. Zhao, David A. Theilmann, T. A. Grigliatti, Dwayne D. Hegedus, H. W. Brock, John E. Phillips, Tom A. Pfeifer, Y. J. Wang
Rok vydání: 1999
Předmět:
Zdroj: Archives of Insect Biochemistry and Physiology. 42:245-252
ISSN: 1520-6327
0739-4462
DOI: 10.1002/(sici)1520-6327(199912)42:4<245::aid-arch3>3.0.co;2-w
Popis: We have produced an active form of Schistocerca gregaria ion transport peptide (ITP) in an insect cell expression system. Transformed Drosophila Kc1 cells secreted a form of ITP into the cell culture medium that was proteolytically cleaved correctly at the amino (N)-terminus. Concentrated culture supernatant from transformed Kc1 and Hi5 cells had high biological activity when tested on isolated locust ilea. Conversely, ITP expressed by baculovirus-infected Sf9 cells was larger in size and had decreased specific activity compared to ITP produced by Kc1 cells due to incorrect cleavage of the peptide at the N-terminus in the baculovirus system. This demonstrates how processing of the secreted foreign protein (ITP) expressed under the late polyhedrin promoter is compromised in a baculovirus-infected cell. Transient transformation of Kc1 cells results in supernatants containing two forms of ITP; one form (A) co-elutes with synthetic ITP and the other form (B) has reduced electrophoretic mobility. In contrast, in stably transformed Kc1 cell supernatant, ITP is expressed in a single form, which has the same electrophoretic mobility and specific biological activity as form A produced by transiently transformed Kc1 cells. Arch. Insect Biochem. Physiol. 42:245–252, 1999. © 1999 Wiley-Liss, Inc.
Databáze: OpenAIRE
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