Transgenic hairy roots, an interesting model system to study the potential of plant species to remediate a mixture of contaminants

IBAÑEZ S; SUMAN J; ONTAÑON O.M; TALANO MA; MEDINA MI; AGOSTINI E; MACEK T

Congreso; Plant Biotechnology: Green for good; 2015

Hairy roots (HR) have emerged as an interesting model system to explore the potential of plants to remediate contaminated environment. Roots are the first organ having contact with contaminants and the use of genetic tools allows obtaining transgenic HR tailored for phytoremediation. The aim of this work was to prepare transgenic tobacco (Nicotiana tabacum) HR with increased ability to remove inorganic (metals/heavy metals) and organic contaminants (phenol). Supertransgenic plants, harbouring RaCd3 gene (improving Zn and Cd phytoextraction) and tpx1 gene (increasing phenol removal) were obtained. The genes were first cloned together in the binary vector p-Green 0029 and competent cells of Agrobacterium tumefaciens C58C1 were transformed by electroporation. The obtained double-transgenic bacterium was used to transform tobacco leaf discs. Finally leaf explants from different confirmed supertransgenic plant lines were agro-infected with A. rhizogenes LB9402 strain to obtain HR. After efficient transformation several clones of supertransgenic HR were obtained. The presence of rolC, RaCd3 and tpx1 genes was demonstrated in the supertransgenic lines selected according to morphological and physiological criteria (bright colour, fast growth). Explants showing de-differentiation, forming calli or regenerating plants were discarded. These HR cultures represent an interesting model system for phytoremediation technology to improve removal efficiency of mixed pollutants and also to explore the contribution of the above genes in plant root tissues.