Proceedings of the XLVI Italian Society of Agricultural Genetics - SIGA Annual Congress

Giardini Naxos, Italy - 18/21 September, 2002

ISBN 88-900622-3-1

Poster Abstract - 2.09

PROLAMIN COMPOSITION AND MIXING PROPERTIES OF TRANSGENIC DURUM WHEAT LINES WITH A " DOWN-REGULATE" TRAFFICKING OF GLUTEN PROTEINS THROUGH THE SECRETORY SYSTEM

LAMACCHIA C.*, FARES C.**, PADALINO L.**, RIEFOLO C.**, GIOVANNIELLO V.**, BORRELLI G.**, LA NOTTE E.*, SHEWRY P.***

*) Istituto di Produzione e Preparazione Alimentare, Università degli studi di Foggia, Facoltà di Agraria, Via Napoli 25, 71100, Foggia Italy

**) Istituto Sperimentale per la Cerealicoltura, Sezione di Foggia, SS 16 Km 675, 71100 Foggia, Italy

***) IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol, BS41 9AF, UK

The trafficking of gluten proteins is important in establishing protein:protein interactions which affect the structure and functional properties of the gluten in the mature grain and in derived flours. The transport of protein vesicles from the ER to the Golgi apparatus is thought to be mediated by the Rab1 class of small GTP-binding proteins. Here, the effect of the manipulation of this transport step, to "down-regulate" trafficking of gluten proteins through the secretory system, on gluten composition and mixing properties was studied.

Durum wheat lines were transformed with a wild type tobacco rab1 cDNA and with a trans-dominant mutant form (Andreeva et al., 1997) of the same cDNA both under the control of the endosperm- specific HMW glutenin subunit promoter (Lamacchia et al., 2001). Electronic microscopy analysis performed on the transgenic starchy endosperms showed that the disruption of the RAb1-dependent transport of vesicles from the ER to the Golgi apparatus (by overexpression of the tobacco mutant Rab1 protein) had a clear effect on the alteration of the deposition of some prolamins in protein bodies. Analyses of the prolamin composition of these lines show a variation of the total prolamin amount and distribution with an effect also on the mixing properties.