Les séminaires ont lieu sur le Campus Montpellier SupAgro/INRA de La Gaillarde (2, place P. Viala Montpellier)
Jeudi 17 avril 2014
Amphi 208 (Cœur d’école) à 14h
New insights into mechanism of auxin transport on cellular level
Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Czech Republic
Auxin (indole-3-acetic acid) is one of the most important plant hormones involved in control of morphogenesis; therefore, it is indispensable for “shaping the plant” and for plant responses to environmental stimuli. Besides, auxin functions also as mobile signal between cells, tissues and organs, thus securing spatial and temporal coordination of the whole plant development. The manipulation of auxin distribution and endogenous content leads to massive effects on plant phenotype. The mode of auxin action is closely bound up with its specific polar cell-to-cell transport resulting in uneven auxin distribution within tissues. Such movement of auxin along plant body is mediated by activities of auxin transporters – influx and efflux carriers. Recently, a novel and unique property of some auxin transporters was found: these transporters can switch from influx to efflux mode with respect intracellular auxin content, and in relation to environmental conditions. Moreover, there is a so far unknown link between enhanced activity of auxin transporters and auxin metabolism – probably to maintain natural intracellular auxin level. Thanks to mathematical modelling of cellular auxin accumulation, it is now possible to describe kinetics and capacity of selected carriers in detail, and to estimate its share in total auxin transport on the tissue level. Such findings have a potential to contribute significantly to the overall knowledge about both mechanism of auxin transport on cellular level and its possible impact on plant growth and development..
Contact : Philippe Nacry