RT Journal Article
T1 Molecular Characterization of ZosmaNRT2, the Putative Sodium Dependent High-Affinity Nitrate Transporter of Zostera marina L.
A1 Rubio-Valverde, Lourdes
A1 Días-García, Jordi
A1 Amorim-Silva, Vitor
A1 Macho, Alberto P.
A1 Botella-Mesa, Miguel Ángel
A1 Fernández-García, José Antonio
K1 Zostera marina
K1 Genómica
K1 Flora marina - Metabolismo
AB One of the most important adaptations of seagrasses during sea colonization was the capacity to grow at the low micromolar nitrate concentrations present in the sea. In contrast to terrestrial plants that use H+ symporters for high-affinity NO3− uptake, seagrasses such as Zostera marina L. use a Na+-dependent high-affinity nitrate transporter. Interestingly, in the Z. marina genome, only one gene (Zosma70g00300.1; NRT2.1) is annotated to this function. Analysis of this sequence predicts the presence of 12 transmembrane domains, including the MFS domains of the NNP transporter family and the “nitrate signature” that appears in all members of the NNP family. Phylogenetic analysis shows that this sequence is more related to NRT2.5 than to NRT2.1, sharing a common ancestor with both monocot and dicot plants. Heterologous expression of ZosmaNRT2-GFP together with the high-affinity nitrate transporter accessory protein ZosmaNAR2 (Zosma63g00220.1) in Nicotiana benthamiana leaves displayed four-fold higher fluorescence intensity than single expression of ZosmaNRT2-GFP suggesting the stabilization of NRT2 by NAR2. ZosmaNRT2-GFP signal was present on the Hechtian-strands in the plasmolyzed cells, pointing that ZosmaNRT2 is localized on the plasma membrane and that would be stabilized by ZosmaNAR2. Taken together, these results suggest that Zosma70g00300.1 would encode a high-affinity nitrate transporter located at the plasma membrane, equivalent to NRT2.5 transporters. These molecular data, together with our previous electrophysiological results support that ZosmaNRT2 would have evolved to use Na+ as a driving ion, which might be an essential adaptation of seagrasses to colonize marine environments.
PB MDPI
YR 2019
FD 2019-07-26
LK https://hdl.handle.net/10630/34680
UL https://hdl.handle.net/10630/34680
LA eng
NO Rubio L, Díaz-García J, Amorim-Silva V, Macho AP, Botella MA, Fernández JA. Molecular Characterization of ZosmaNRT2, the Putative Sodium Dependent High-Affinity Nitrate Transporter of Zostera marina L. International Journal of Molecular Sciences. 2019; 20(15):3650. https://doi.org/10.3390/ijms20153650
NO This work was supported by the Spanish Ministerio de Economía y Competitividad (cofinanced by the European Regional Development Fund; grant BFU2017-85117-R participated by J.A.F. and L.R. and BIO2017-82609-R to M.A.B). J.D.-G. is beneficiary of a Málaga University PhD contract (E-29-2019-0101454). V.A.-S is beneficiary of a post-doc contract funded by BIO2017-82609-R.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 19 ene 2026