title: A Kunitz type protease inhibitor related protein is synthesized in Drosophila prepupal salivary glands and released into the moulting fluid during pupation.
abstract: From the Drosophila virilis late puff region 31C, we microcloned two neighbouring genes, Kil-1 and Kil-2, that encode putative Kunitz serine protease inhibitor like proteins. The Kil-1 gene is expressed exclusively in prepupal salivary glands. Using a size mutant of the KIL-1 protein and MALDI-TOF analysis, we demonstrate that during pupation this protein is released from the prepupal salivary glands into the pupation fluid covering the surface of the pupa. 3-D-structure predictions are consistent with the known crystal structure of the human Kunitz type protease inhibitor 2KNT. This is the first experimental proof for the extracorporal presence of a distinct Drosophila prepupal salivary gland protein. Possible functions of KIL-1 in the context of the control of proteolytic activities in the pupation fluid are discussed.
authors.affiliation: Institut für Biologie-Genetik, Freie Universität Berlin, Arnimallee 7, D-14195, Germany. kress@zedat.fu-berlin.de
authors.forename: Horst
authors.initials: H
authors.lastname: Kress
authors.forename: Andres
authors.initials: A
authors.lastname: Jarrin
authors.forename: Eduardo
authors.initials: E
authors.lastname: Thüroff
authors.forename: Robert
authors.initials: R
authors.lastname: Saunders
authors.forename: Chris
authors.initials: C
authors.lastname: Weise
authors.forename: Marcel
authors.initials: M
authors.lastname: Schmidt am Busch
authors.forename: Ernst-W
authors.initials: EW
authors.lastname: Knapp
authors.forename: Marianne
authors.initials: M
authors.lastname: Wedde
authors.forename: Andreas
authors.initials: A
authors.lastname: Vilcinskas
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D007611:Aprotinin / Q000737:chemistry*; D001483:Base Sequence; D003001:Cloning, Molecular; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development; D010450:Endopeptidases / Q000378:metabolism; D019143:Evolution, Molecular; D017344:Genes, Insect / Q000235:genetics; D007814:Larva / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D020161:Physical Chromosome Mapping; D011679:Pupa / Q000235:genetics / Q000378:metabolism; D012469:Salivary Glands / Q000254:growth & development* / Q000378:metabolism*; D012471:Salivary Proteins and Peptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020539:Sequence Analysis, Protein; D014361:Trypsin Inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D012471:Salivary Proteins and Peptides; D014361:Trypsin Inhibitors; D007611:Aprotinin; D010450:Endopeptidases