Doctorate thesis
Thursday, June 30, 2016
Sudy of interactions between heavy metals and phosphate homeostasis in plants : physiological and molecular basis
Nadia Bouain
BPMP, “Metal phytotoxicity” team
Jury :
M. Chedly ABDELLY, CoDirecteur de thèse, Professeur
M. Hatem ROUACHED, Directeur de thèse, Chargé de Recherche
M. Thierry DESNOS, Examinateur, Directeur de Recherche
M. Moez HANIN, Rapporteur, Professeur
M. David MACHEREL, Rapporteur, Professeur
Mme Najoua Karray BOURAOUI, Examinateur, Professeur
Abstract :
Plants require a variety of elements for their basic biological functions. Interestingly, Transport, assimilation and utilization of these nutrients are not independent of another. However, the biological significance, molecular and genetic bases of these dependencies are not well understood. We use the over-accumulation of inorganic phosphate (Pi) in plants under zinc (Zn) deficiency as an example to dissect a fundamentally and agronomically important Pi-Zn interdependency in Lettuce, rice and Arabidopsis plants. We described the physiological and molecular basis of the interaction between Pi and Zn homeostasis. In Lettuce, we revealed a contrasting behavior between the two lettuce varieties in terms of the coregulation of Pi and Zn homeostasis. In rice, our data reveal coordination between pathways involved in Fe transport and PiZn signaling, which involves the OsPHO1; 1. In Arabidopsis, we discovred a new mecanism that plants use to gate defense and growth process in Pi-Zn dependant manner.