Use of transformed tobacco plants with endogenous altered polyamines pools for studying the regulation of mycorhization

MONTES M. MARINA M, CALVO C. MENÉNDEZ A. AND RUIZ O.A.

Pinamar. Buenos Aires. Argentina

Congreso; XX Annual Meeting of Argentine Society for Biochemistry and Molecular Biology Research. X Congress of Panamerican Association for Biochemistry and Molecular Biology.; 2005

SAIB-PABMB

A number of regulatory mechanisms of plant defence response have been described during the establishment of the arbuscular mycorrhizal (AM) In this work, we tested an experimental design including the use of transformed tobacco plants with endogenously altered polyamine pools, for studying the putative role of these polycations on the regulation of AM infection. Transgenic tobacco plants containing the oat arginine decarboxylase (ADC) gene under the control of a tetracycline-inducible promoter, mycorrhized or not with Glomus intraradices were used. Tetracycline induction decreased free spermine levels in non-mycorrhized plants transformed with the ADC gene, and increased putrescine pools in mycorrhized plants transformed with the ADC gene. There were no differences in mycorrhization parameters between control plants induced or not with tetracycline, whereas transformed plants, showed slightly, higher levels of mycorrhizal root length, entry points and vesicles due to tetracycline induction. However the absence of any significant correlation between shoot polyamine levels and mycorrhizal parameters suggests that these levels may be not directly involved in the regulation of fungal growth within the roots. Results are discussed regarding the improvement of experimental design.