Overexpression of a phosphate transporter gene ZmPt9 from maize influences growth of transgenic Arabidopsis thaliana

Phosphate transporters (PHTs) are well-known for their roles in phosphate uptake in plants. However, their actions in imparting plant growth in plants are still not so clear. In our previous study, we observed that maize PHT1 gene ZmPt9 plays a significant role in phosphate uptake. In this study, we further characterized ZmPt9 in response to low phosphate condition through ZmPt9 promoter inductive analysis by GUS staining and quantification. To elucidate the function of ZmPt9, we generated overexpression plant in Arabidopsis. ZmPt9 overexpressing Arabidopsis plants conferred small leaves and early flowering compared with the wild-type plants. In addition, ZmPt9 can complement the late flowering phenotype of Arabidopsis mutant pht1;2. The qRT-PCR analysis revealed that overexpression of ZmPt9 in Arabidopsis changed expression levels of some flowering-related genes. Further expressed detection of hormone related genes revealed that GA and auxin maybe the main determinant for growth influences of ZmPt9. In conclusion, these results suggest that apart from phosphate transport activity, ZmPt9 can be further exploited for improving crops growth. (c) 2020 Elsevier Inc. All rights reserved.

Automated summary

Phosphate transporters like ZmPt9 play a significant role in phosphate uptake in plants, but this study suggests that ZmPt9 also influences plant growth and flowering in addition to its transport activity. Overexpressing ZmPt9 in Arabidopsis resulted in small leaves and early flowering, as well as complementing the late flowering phenotype of a mutant. Additionally, changes in expression levels of flowering-related genes and the influence of hormones like GA and auxin were observed, indicating the potential for ZmPt9 in improving crop growth.