Genome-Wide Identification and Functional Characterization of the Phosphate Transporter Gene Family in Sorghum

The phosphate transporter (PHT) family mediates the uptake and translocation of the essential macronutrient phosphorus (P) in plants. In this study, 27 PHT proteins in Sorghum were identified via bioinformatics tools. Phylogenetic analysis of their protein sequences in comparison with those family proteins from Arabidopsis and rice indicated that these proteins could be clustered into five typical subfamilies. There are 12 SbPHT1 members, one SbPHT2, six SbPHT3s, six SbPHT4s, and two SbPHOs in Sorghum. Further analysis of the gene structure, conserved motifs, subcellular localization, and transmembrane domains suggested that these features are relatively conserved within each subfamily. Meanwhile, the qRT-PCR assay implied that SbPHT1;2, SbPHT1;11, and SbPHT4;6 were significantly upregulated in roots when exposed to low-phosphate conditions, suggesting that these genes might be involved in P uptake in low-phosphate conditions. Our study will increase our understanding of the roles of phosphate transporters in Sorghum.