Agrobacterium tumefaciens versus Rhizobium rhizogenes: Az Arabidopsis thaliana redox homeosztázisának megfigyelésére szolgáló két transzformációs technika összehasonlítása = Agrobacterium tumefaciens versus Rhizobium rhizogenes: A comparison of two transformation techniques for monitoring redox homeostasis of Arabidopsis thaliana

Genetic transformation is an essential tool for analyzing gene function in plants. A. tumefaciens and R. rhizogenes are soil-borne Gram-negative bacteria, causative agents of crown gall and hairy roots, respectively. This research aimed to determine whether stable transformants of Arabidopsis thaliana ecotype Col-0 obtained by the A. tumefaciens-mediated floral dip transformation differ in the cellular redox state from non-stable transformants generated by R. rhizogenes-mediated hairy root transformation. To obtain information about the cellular redox state, we introduced and expressed the redox-sensitive green fluorescent protein construct containing a fusion product of the human glutaredoxin (GRX1-roGFP2), which allows dynamic live imaging of the glutathione redox potential (EGSH) with high sensitivity. To develop an efficient R. rhizogenes-mediated transformation method on Arabidopsis, we analyzed the effects of various environmental, nutritional, and procedural conditions on transformation efficiency. The dynamic changes of EGSH were measured in wild-type (WT), glutathione reductase 1, and dehydroascorbate reductase 2 mutant plants via confocal microscopy over 60 min following treatment with 150 mM NaCl or 300 mM mannitol. Based on our results, similar EGSH values were measured in roGFP2 expressing WT and mutant plants produced by two different transformation techniques under control conditions and after stress treatments too. Transformation mediated by R. rhizogenes has proved a faster and more feasible genetic manipulation in a relatively short time. This method can be used to analyze redox changes in response to stresses or for functional analysis of different genes. This study was supported by the Hungarian National Research, Development, and Innovation Office (Grant Number: NKFIH 6 K 138589).