A chymotrypsin-like serine protease interacts with the chitin synthase from the midgut of the tobacco hornworm.
The chitin portion of the peritrophic matrix in the midgut of the tobacco hornworm, Manduca sexta, is produced by chitin synthase 2 (CHS2), a transmembrane family II glycosyltransferase, located at the apical tips of brush border microvilli. To look for proteins that potentially interact with CHS2, we performed yeast two-hybrid screening, identifying a novel chymotrypsin-like protease (CTLP1) that binds to the extracellular carboxyterminal domain of CHS2. The occurrence of this interaction in vivo is supported by co-localization and co-immunoprecipitation data. Based on our findings we propose that chitin synthesis is controlled by an intestinal proteolytic signalling cascade linking chitin synthase activity to the nutritional state of the larvae.
Broehan
Gunnar
G
Department of Biology/Chemistry, University of Osnabrück, D-49069 Osnabrück, Germany.
Zimoch
Lars
L
Wessels
Anton
A
Ertas
Beyhan
B
Merzendorfer
Hans
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002686:Chitin / Q000096:biosynthesis; D002687:Chitin Synthase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D053818:Chymases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D004064:Digestive System / Q000166:cytology / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic; D007150:Immunohistochemistry; D047468:Immunoprecipitation; D018402:Manduca / Q000166:cytology / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D020798:Two-Hybrid System Techniques
D018076:DNA, Complementary; D012333:RNA, Messenger; D002686:Chitin; D002687:Chitin Synthase; C400821:chitin synthase 2; D053818:Chymases