Genome-Wide Identification, Expression Profiling, and Evolution of Phosphate Transporter Gene Family in Green Algae.

Phosphorus (P) is an essential nutrient for plant growth and development. Phosphate transporters (PHTs) are -membrane proteins that mediate the uptake and translocation of phosphate (Pi) in green plants. The PHT family including PHT1, PHT2, PHT3 and PHT4 subfamilies are well-studied in land plants; however, PHT genes in green algae are poorly documented and not comprehensively identified. Here, we analyzed the PHTs in a model green alga and found 25 putative PHT genes, which can be divided into four subfamilies. The subfamilies of CrPTA, CrPTB, CrPHT3, and CrPHT4 contain four, eleven, one, and nine genes, respectively. The structure, chromosomal distribution, subcellular localization, duplication, phylogenies, and motifs of these genes were systematically analyzed . Expression profile analysis showed that CrPHT genes displayed differential expression patterns under P starvation condition. The expression levels of and were down-regulated, while the expression of most genes was up-regulated under P starvation, which may be controlled by CrPSR1. The transcript abundance of most and genes was not significantly affected by P starvation except , , and . Our results provided basic information for understanding the evolution and features of the PHT family in green algae.