Fig. 5: Transport mechanism of XPR1.
From: Structure and function of human XPR1 in phosphate export
a The electron microscopy density map of HsXPR1spx. b Comparison of HsXPR1spx (cyan) and XPR1InsP6 (salmon, EMD-38068)Â maps in different views. The InsP6 and C-terminal loop in the XPR1InsP6 map are shown in yellow and purple, respectively. c Working model for phosphate transport. When intracellular phosphate levels are low, HsXPR1 can switch between the flexible SPX state (left panel) and the V-shaped state (middle panel). When intracellular phosphate levels are high, InsPs binding leads to the rearrangement of the SPX domains and the activation of XPR1 (right panel). Inorganic phosphate (Pi) is displayed as yellow spheres.
