Overexpression ofMdPHR1Enhanced Tolerance to Phosphorus Deficiency by IncreasingMdPAP10Transcription in Apple (Malus x Domestica)

摘要

Phosphorus is an essential nutrient during plant growth and development. It is involved in the formation of important compounds in plants, such as phospholipids, ATP, and nucleic acids. However, phosphorus is distributed unevenly in most soils, and exists primarily in the form of organophosphorus, which plants cannot use. In this study, theAtPHR1homologMdPHR1was identified in apple. Our results showed that MdPHR1 contained a MYB domain and a coiled-coil domain, which were conserved in AtPHR1. TheMdPHR1transgenic lines had higher acid phosphatase activity and phosphorus content than the wild-type under phosphorus limited conditions. Overexpression ofMdPHR1enhanced tolerance to phosphorus deficiency in apple calli andArabidopsisseedlings, and MdPHR1 could bind to the P1BScis-element ofMdPAP10and activated its transcription. Collectively, our experimental evidence suggests that MdPHR1 may be the central regulator of the system controlling transcriptional responses to Pi starvation in apple.