Analysis of the NRT2 Nitrate Transporter Family in Arabidopsis. Structure and Gene Expression

AUTOR(ES)

Orsel, Mathilde

FONTE

American Society of Plant Physiologists

RESUMO

Nitrate is an essential element for plant growth, both as a primary nutrient in the nitrogen assimilation pathway and as an important signal for plant development. The uptake of nitrate from the soil and its translocation throughout the plant has been the subject of intensive physiological and molecular studies. Using a reverse genetic approach, the AtNRT2.1 gene has been shown to be involved in the inducible component of the high-affinity nitrate transport system in Arabidopsis. The Arabidopsis Genome Initiative has released nearly the whole genome sequence of Arabidopsis, allowing the identification of a small NRT2 multigene family in this species. Thus, we investigated the phylogenetic relationship between NRT2 proteins belonging to several kingdoms and compared the structure of the different members of the Arabidopsis family. We analyzed, by semiquantitative reverse transcriptase-polymerase chain reaction, the expression pattern of each gene depending on plant organ and development or nutritional status, and compared the relative level of each gene by real-time polymerase chain reaction. We also evaluated the significance of each paralog on the basis of the relative levels of gene expression. The results are discussed in relation with distinct roles for the individual members of the AtNRT2 family.

Documentos Relacionados

• Transcript Profiling in the chl1-5 Mutant of Arabidopsis Reveals a Role of the Nitrate Transporter NRT1.1 in the Regulation of Another Nitrate Transporter, NRT2.1W⃞
• Gene Expression of the NO3– Transporter NRT1.1 and the Nitrate Reductase NIA1 Is Repressed in Arabidopsis Roots by NO2–, the Product of NO3– Reduction
• The Arabidopsis Nitrate Transporter NRT1.7, Expressed in Phloem, Is Responsible for Source-to-Sink Remobilization of Nitrate[W][OA]
• The Nitrate Transporter AtNRT1.1 (CHL1) Functions in Stomatal Opening and Contributes to Drought Susceptibility in Arabidopsis
• EIN4 and ERS2 are members of the putative ethylene receptor gene family in Arabidopsis.