Characterization of the promoter of phosphate transporter TaPHT1.2 differentially expressed in wheat varieties.
TaPHT1.2 is a functional, root predominantly expressed and low phosphate (Pi) inducible high-affinity Pi transporter in wheat, which is more abundant in the roots of P-efficient wheat genotypes (e.g., Xiaoyan 54) than in P-inefficient genotypes (e.g., Jing 411) under both Pi-deficient and Pi-sufficient conditions. To characterize TaPHT1.2 further, we genetically mapped a TaPHT1.2 transporter, TaPHT1.2-D1, on the long arm of chromosome 4D using a recombinant inbred line population derived from Xiaoyan 54 and Jing 411, and isolated a1,302 bp fragment of the TaPHT1.2-D1 promoter (PrTaPHT1.2-D1) from Xiaoyan 54. TaPHT1.2-D1 shows collinearity with OsPHT1.2 that has previously been reported to mediate the translocation of Pi from roots to shoots. PrTaPHT1.2-D contains a number of Pi-starvation responsive elements, including P1BS, WRKY-binding W-box, and helix-loop-helix-binding elements. PrTaPHT1.2-D1 was then used to drive expression of beta-glucuronidase (GUS) reporter gene in Arabidopsis through Agrobacterium-mediated transformation. Histochemical analysis of transgenic Arabidopsis plants showed that the reporter gene was specifically induced by Pi-starvation and predominantly expressed in the roots. As there is only one SNP between the TaPHT1.2-D1 promoters of Xiaoyan 54 and Jing 411, and this SNP does not exist within the Pi-starvation responsive elements, the differential expression of TaPHT1.2 in Xiaoyan 54 and Jing 411 may not be caused by this SNP.
Miao
Jun
J
The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
Sun
Jinghan
J
Liu
Dongcheng
D
Li
Bin
B
Zhang
Aimin
A
Li
Zhensheng
Z
Tong
Yiping
Y
D017360:Arabidopsis / Q000235:genetics; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003001:Cloning, Molecular; D017124:Conserved Sequence; D015870:Gene Expression; D008969:Molecular Sequence Data; D028061:Phosphate Transport Proteins / Q000235:genetics*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics*; D018517:Plant Roots / Q000235:genetics; D011401:Promoter Regions, Genetic; D016415:Sequence Alignment; D014908:Triticum / Q000145:classification / Q000235:genetics*
D028061:Phosphate Transport Proteins; D010940:Plant Proteins