Study of transcription factors involved in the response to salt stress in Medicago truncatula

FEDERICO ARIEL; VERONIQUE GRUBER; MARTIN CRESPI; RAQUEL CHAN

Rosario

Congreso; XLII Reunión Anual de SAIB; 2006

SAIB

Medicago truncatula is considered a model legume. Its root architecture is determined by the action of environmental stresses on specific genes, whose role is to adapt root development to this constraint. In this work, we study the role of certain Transcription Factors (TFs) involved in the response to salt stress.    In order to choose the genes we would study, experimental conditions were set so as to affect root growth and detect recovery after a salt stress. Rapid responses (1h and 6h) in root tissues were analysed in M. truncatula using genomic approaches (16K array). Then, massive quantitative RT-PCR was used to identify the specific TFs linked to early salt stress responses. Regulation of a few candidate TFs from several families, such as HD-ZIP, NAC, RR and WRKY, has been analysed in more detail and a complete organ pattern of expression has been determined for each of them. Additionally, the cDNA clones of these TFs were obtained with the aim of overexpressing them in Medicago hairy roots, as well as in Arabidopsis plants. Besides, the in vitro analysis of these proteins let us to determine their DNA binding sties. In conclusion, all these approaches as a whole aim to dissect the regulatory pathways involved in the response to salt stress in legume roots and eventually identify genes able to confer plants tolerance to such adverse environmental conditions.