The genomic organization and transcriptional pattern of genes encoding nitrate transporters 1 (NRT1) in cucumber

Abstract

NRT1 proteins are H + -coupling nitrate transporters which belong to the family of peptide transporters (PTRs) and facilitate low and high affinity nitrate transport systems in a model plant Arabidopsis thaliana . In this study, we present the first inventory of the Cucumis sativus NRT1 family together with the transcriptional profile of CsNRT1 genes suggesting the physiological function of the family members in cucumber. Semiquantitative RT- PCR was used to analyze the level and organ-distribution of expression of CsNRT1 genes. The response of those CsNRT1s , whose transcripts were clearly detectable in vegetative tissues to different level of nitrate supply was examined through real-time PCR assays. The newly identified cucumber NRT1s were given the designation according to their homology to A. thaliana AtNRT1s. The comparison of the Arabidopsis and cucumber NRT gene families, similarly to the previous comparison of NRT1s in Arabidopsis , poplar and grasses, reveals some striking differences in genes’ structure and quantity. The putative function of particular CsNRT1 proteins is discussed, considering the results obtained here as well as the already published studies on A. thaliana NRT1 transporters.