Biological Analysis and Response to Low Phosphate Stress of Phosphate Transporter Family 1 (PHT1) Genes in Solanum tuberosum L.

Inorganic phosphate (Pi) is one of the main nutrients necessary for plant growth. Phosphate transporters mediate the acquisition, transport and recycling of phosphate, which is essential for plant growth and development. Although PHT1 has been reported in many plants at home and abroad, it is rarely studied in potato. Therefore, it is of great significance to study the PHT1 family members in order to understand the molecular response mechanism of potato in low phosphate state. In this study, a total of 6 potato PHT1 genes were identified and isolated. It was found that after the expression of different members of potato PHT1 gene, there were certain differences in amino acids and proteins, and the transmembrane domains ranged from 6 to 12. The difference in the secondary and tertiary protein structure of potato PHT1 also led to a difference in protein morphology. In addition, the expression of the PHT1 gene in potato increased obviously during 3 similar to 9 h of Pi deficiency stress. Overall, the expression levels of different genes in roots, stems and leaves are distinctly different, but the expression levels of the StPHT1;6 and StPHT1;10 genes are very high in roots, stems and leaves, indicating that these two genes may participate in the absorption of Pi in potato and play a role in Pi translocation. These two genes play a major role in the regulation of expression under short-term Pi deficiency stress. Our results provide an important reference for further understanding the evolution and function of potato phosphate transporters, and have important significance for improving the ability of potato to tolerate low Pi.