A working model for the roles of PHT1;7 in P redistribution in rice (O. sativa). A, Role of PHT1;7 in the short distance transfer of P in source leaf. P from mesophyll cells or MS cells is exported into apoplastic space by (an) unknown Pi efflux transporter(s). PHT1;7 located in VB sheath cells and CCs imports P from apoplast. P in CCs is further transferred to SEs through plasmodesmata. B, Role of PHT1;7 in nodes. P is loaded into the phloem in both EVBs and DVB/RVB by PHT1;7 and OsPHT1;3.