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

Salsomaggiore Terme, Italy - 26/29 September, 2001

ISBN 88-900622-1-5

 

Poster Abstract

 

 

EXPRESSION OF THE MAIZE B32 RIP PROTEIN IN RICE (ORYZA SATIVA L.) UNDER VARIOUS PROMOTERS

 

REALI A.*, MESSEGUER J.**, PEÑAS G.**, CARRARA N.*, CONTI E.*, GAVAZZI F.*, FORLANI F.***

 

* Istituto Sperimentale per la Cerealicoltura, Sezione di Bergamo

eurice.elu@spm.it

** Institut de Recerca i Tecnologia Agroalimentàries - I.R.T.A., Departament de Genètica Vegetal, Centre de Cabrils, Barcelona, Spain

*** Dipartimento di Scienze Molecolari Agroalimentari, Università degli studi di Milano

 

 

Rice (Oryza sativa L.), genetic transformation, RIP, promoters, defence genes

 

The main objective of our studies on rice is focused on the introduction of the maize gene b32 into European varieties and investigations on its potential role of defence gene against fungal pathogens. Expression vectors for the introduction of the b32 maize gene in rice (Oryza sativa spp. japonica) were constructed considering three different promoters. Two constitutive promoters, p35S CaMV and pUbi1, were expected to express the b32 gene constitutively during the life cycle of the plant and the prbcS promoter  was expected to express b32 only in green tissues. Transgenic rice plants were produced via biolistics using mature embryo-derived primary calli as target tissues. Regenerated plants containing the maize gene were micropropagated in vitro and subsequently transferred into greenhouse and grown to maturity. Three independent events of transformation for each promoter were chosen for further investigation. Molecular analyses confirmed gene integration and western analyses showed that the b32 protein was consistently expressed in leaf tissues of T0 in vitro plantlets. The same analyses confirmed that its expression lasted in time from the young to mature plant stages. A detailed analysis was accomplished for the several independent events of transformation related to the expression levels in the plant tissues, with the different promoters.