http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Tue, 21 May 2013 00:48:54 GMT 2013-05-21T00:48:54Z http://hdl.handle.net/2067/2261 Title: Livelli di attività antiproteinasiche in piante transgeniche di pomodoro esprimenti inibitori di proteinasi a serina e a cisteina Authors: Farisei, Francesca; Panichi, Daniela; Poerio, Elia; Speranza, Stefano; Pucci, Claudio; Fonzo, Valentina; Caccia, Riccardo; Soressi, Gian Piero Abstract: Tomato plants transgenic for genes coding for protein inhibitors, were tested in order to evaluate their capability to inhibit the commercial proteinase activities as well as those present in the midgut of the phytophagous insect Helicoverpa armigera. Leaf extracts of Pi-IV (gene from soybean coding for a Bowman-Birk-like trypsin inhibitor) transgenic T3 plants (cv. UC-82) are able to inhibit bovine pancreatic trypsin and trypsin-like activity of the phytophagous insect 4 times more than control plant extracts; extracts of KTI3 (gene from soybean coding for a Kunitz-like tripsine inhibitor) transgenic T3 plants (cv. Riogrande) are able to inhibit bovine pancreatic trypsin and trypsin-like activity of the insect 200 times more than control plant extracts; leaf extracts of AtCys (gene from Arabidopsis coding for a cysteine protease inhibitor) transgenic T2 plants (cv. Riogrande) are able to inhibit commercial papain and cysteine-like activity of the insect 4 times more than control plant extracts. On the basis of the data it would be interesting, for both speculative and applicative purposes, to use these transgenic plants in order to verify in vivo the action on the mortality and/or on the reproduction ability of the H. armigera, particularly dangerous to the tomato crop. Wed, 31 Dec 2003 23:00:00 GMT http://hdl.handle.net/2067/2261 2003-12-31T23:00:00Z http://hdl.handle.net/2067/2322 Title: BBI and Kunitz serin-protease inhibitor action in tomato transgenic plants towards Helicoverpa armigera larvae Authors: Caccia, Riccardo; Schettino, Maria; Farisei, Francesca; Savazzini, Federica; Poerio, Elia; Speranza, Stefano; Pucci, Claudio; Soressi, Gian Piero Abstract: Several crop varieties with agronomically-compatible levels of resistance to insects have been generated by Bt gene transfer. Plant proteinaceous proteinase inhibitors have potential for increasing resistance of crop to insect pests. Proteolytic activities in the larval guts of Helicoverpa armigera (a major pest of solanaceae) have been investigated and proved to be largely due to extracellular serine proteinases (trypsin- and chymotrypsin-like activities) with alkaline pH optimum. With the aim of obtaining tomato transgenic plants resistant to H. armigera larvae, we transformed - the cultivar Riogrande with the gene KTI3 (coding for a soybean Kunitz Inhibitor) and the cultivar UC-82 with the gene Pi-IV (coding for a soybean Bowman-Birk Inhibitor). Leaf extracts of transgenic plants contained significant levels of inhibitory activities towards both bovine pancreatic trypsin and insect trypsin-like enzyme, on average 187- and 5-fold higher-than controls, respectively. The trypsin inhibiting activity was found stable atdifferent plant phenological phases in fruits and leaves; this activity resulted stable for 24h in detached leaf discs used to feed insects. Both inhibiting activities were able to contrast development of H. armigera larvae, by interferring with midgut trypsin-like activity that was found higher in III-IV ages than other ages. Thu, 31 Dec 1998 23:00:00 GMT http://hdl.handle.net/2067/2322 1998-12-31T23:00:00Z