Molecular characterization and expression analysis of phosphate transporter gene TaPT2-1 in wheat (Triticum aestivum L.)

Abstract

A transcript-derived fragment (TDF) showing up-regulated expression under low Pi stress and being identical to an uncharacterized phosphate transporter gene TaPT2-1 was cloned in wheat. TaPT2-1 was 2075 bp in length and encoded a 568-aa polypeptide. Transmembrane prediction analysis suggested that TaPT2-1 had 13 conserved transmembrane domains. TaPT2-1 shared much higher similarities to other four homologs from Arabidopsis thaliana, Solanum tuberosum, Capsicum frutescens, and Solanum melongena. The expression of TaPT2-1 was root specific and low Pi inducible, suggesting that it plays roles in roots and is involved in the Pi acquisition under Pi-starved condition. The promoter region of TaPT2-1 was cloned based on genome walk analysis. Several types of cis-regulatory elements, such as low Pi responding and tissue specific, were identified in TaPT2-1 promoter. The transgenic tobacco plants with the integrated TaPT2-1 promoter GUS were generated, and GUS histochemical staining analysis in the roots and leaves of the transgenic plants was performed. The results of GUS staining in roots and leaves under various Pi supply conditions were in accordance with the TaPT2-1 transcripts detected based on RT-PCR analysis. Taken together, the distinct expression of low Pi-induced and root-specific TaPT2-1 suggested that it could be used as the potential gene resource on generation of elite crop germplasms with high Pi use efficiency in the future.

Identification and validation of organ-preferential genes and analysis of corresponding upstream tissue-specific promoters in wheat

“…Wheat is an important cereal crop in the world, but research on tissue-specific promoters in this plant species is limited compared to the other two cereal crops rice and maize, due to its complex allohexaploid genome and low transformation efficiency (He et al 2015). Previous works demonstrated that TaPT2 and TaPT2-1 promoters are exclusively active in roots and their activities are phosphate-dependent in transgenic wheat, Arabidopsis, or tobacco (Tittarelli et al 2007, Cui et al 2011, while TaPSG719 and TaPSG076 are pollen-specific promoters (Chen et al 2010(Chen et al , 2012. The TaHMWGlu1D and TaHMWGlu1Bx17 promoters have been reported to drive GUS specific expression in the endosperm of transgenic wheat (Lamacchia et al 2001, Oszvald et al 2007).…”

Genotypic Variation in the Root and Shoot Metabolite Profiles of Wheat (Triticum aestivum L.) Indicate Sustained, Preferential Carbon Allocation as a Potential Mechanism in Phosphorus Efficiency

“…The concentration of P i in the soil is generally much lower than the P i concentration in root cells, thus plants use active transport systems to acquire P from the soil solution. This process is carried out by high-affinity P i /H + symporters that are controlled by two major gene families ( Pht1 and Pht2 ) (Cui et al, 2011). Once in the roots, P i is partly used to synthesize P-containing substances such as ATP or phospholipids, or can be stored in the vacuole, while its main fraction is transported into xylem vessels and allocated to the stem, leaves, flowers, and seeds (Młodzińska and Zboińska, 2016).…”