The photosynthetic response to iron limitation and iron resupply in diatoms

• Applicant: Professorin Julie La Roche, Ph.D.
• Subject Area: Plant Biochemistry and Biophysics
• Term: from 2007 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 45748627

The aim of this project is to elucidate the mechanisms that allow diatoms to modify the stoichiometry of their photosynthetic apparatus and down-regulate carbon fixation in order to grow under iron limited conditions. Because of the chronic iron-limited conditions in vast areas of the ocean, it is important to understand how diatoms can rapidly recover from the iron limited conditions and resume high photosynthetic rates. We propose to study here the down-regulation and recovery of photosynthesis (light absorption and carbon fixation) encountered during the acclimation to Fe-limitation and iron-resupply, respectively. As the diatom iron requirements are very dependent on light intensity, the remodelling of the photosynthetic apparatus will be studied as a function of both light intensity and iron supply. This will be done initially by following the photosynthetic physiology and gene expression of FCP genes known to vary as a function of Fe supply. Furthermore we want to identify the specific role of three FCPs in the acclimation response to iron-limitation.

• DFG Programme: Research Grants