Cloning and expression analysis of the phosphorus transporter gene NtPHT2;1 in Nicotiana tabacum

Abstract

[Objective] Phosphorus absorption and utilization by plants mainly depend on phosphorus transporters, among which the low-affinity phosphorus transporters encoded by the PHT2 family are responsible for the absorption, transport and reuse of phosphate by plants under normal phosphorus conditions. We aim to explore the role and expression pattern of NtPHT2;1 gene in tobacco phosphate transport, and to cultivate new tobacco varieties with efficient phosphorus utilization through NtPHT2;1. [Methods] We cloned NtPHT2;1 using the cDNA of a common tobacco K326 as a template, and conducted bioinformatics analysis and subcellular localization analysis of the protein. The expression pattern of this gene under abiotic stress including low phosphorus were analyzed by fluorescence quantitative PCR. [Results] (1) The total length of NtPHT2;1 gene was 1 764 bp, encoding 587 amino acids. (2) NtPHT2;1 protein was localized to chloroplast. (3) The homology between NtPHT2;1 and CaPHT2;1 protein was 91%. (4) Nt- PHT2;1 promoter contains cis-acting elements involved in the regulation of plant aging and stress. (5) The expression of NtPHT2;1 was the highest in leaves, and expression in new leaves was higher than that in old leaves. There was no significant difference in the expression of this gene under low phosphorus compared with normal conditions. (6) The expression of this gene was decreased significantly under salt stress and drought stress. [Conclusion] NtPHT2;1 gene is involved in phosphate transport and utilization in growth and development of tobacco plants.

Keywords

• nicotiana tabacum
• gene cloning
• ntpht2;1
• expression pattern
• abiotic stress