XIV REUNIÓN DE BIOLOGÍA MOLECULAR DE PLANTAS SALAMANCA, 4-6 de Julio 2018 Name & Surname of the presenting author: Lourdes Rubio E-mail: Lrubio@uma.es Session: Abiotic Stress Communication (Oral or Poster): Póster NRT2.5 A PUTATIVE SODIUM DEPENDENT HIGH AFFINITY NITRATE TRASNPORTER OF ZOSTERA MARINA L. Lourdes Rubio 1 , Jordi Díaz-García 1 , Miguel A. Botella 2 , José A. Fernández 1 . 1 Department of Biología Vegetal, University of Málaga, Málaga, Spain, 2 Deparment of Bioquímica y Biología Molecular, University of Málaga, Málaga, Spain. Corresponding author: Lourdes Rubio (Lrubio@uma.es) Seagrasses are the only group of vascular plants that recolonized the marine environment, possibly the most severe habitat shift ever accomplished by flowering plants. These plants have regained functions enabling them to thrive in liquid medium with an extremely high salinity (0.5 M NaCl), high alkaline conditions (pH 8.2) and very low concentration of essential nutrients as NO 3 - or Pi. Despite this, seagrasses form one of the highest productive and widespread ecosystems of the planet (Larkum et al., 2006). Zostera marina (L.) was the first seagrass fully sequenced and its genome reveals important insights about this secondary adaption (Olsen el al., 2016). Comparison with land plants indicates that less than 20 % of the genes families are specific in the genome of seagrasses (Olsen et al., 2016). Thus, adaptation to marine environment seems to be due to molecular changes of the same family genes rather that the speciation of pre-existing genes. This appears to be the case of the high affinity nitrate transporter belonging to the NRT family. In contrast to terrestrial vascular plants, where NRT2 encode high affinity NO 3 - transporters that operate as H + symporters, our electrophysiological analysis indicate that in Z. marina high affinity NO 3 - uptake is mediated by a Na + -dependent mechanism (Rubio et al., 2005). A detailed analysis of the Z. marina genome indicates the presence of only one gene encoding for this type of transporter: Zosma70g00300.1. Phylogenetic analysis shows that this high affinity nitrate transporter is more related to NRT2.5 than to NTRT2.1, sharing a common ancestor with both, monocot and dicot plants. We have cloned Zosma70g00300.1 and the brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by Repositorio Institucional Universidad de Málaga