Fig. 3: Por1 hexamer has a phospholipid scramblase activity.

a CGMD simulation of Por1(QE) and WT Por1 hexamers were conducted. Three independent simulations were run for 10 μs for Por1(QE) and 30 μs for WT Por1. The protein structures and their initial positions are those at the start of the simulation. Red dots indicate the positions of the phospholipid head groups (PO₄) that underwent scrambling, indicating that scrambling is more likely to occur at the B-C and B’-C’ interfaces. b Each atom of the residues frequently involved in scrambling at the B/C interface is represented by a sphere in both the side view (left) and top view (right), and the corresponding residues are listed (center). Hydrophilic or polar residues are highlighted in red. c Total phospholipids were extracted from the indicated cells grown in YPD containing [³²P]-Pi and analyzed by thin-layer chromatography and radioimaging (Left). CL, cardiolipin; PA, phosphatidic acid; PE, phosphatidylethanolamine; PS, phosphatidylserine: PI, phosphatidylinositol; PC, phosphatidylcholine. The relative amounts of each phospholipid are shown as a percentage of total phospholipids (Top Right) and compared to those in WT control cells (Bottom Right). Values are means ± SEMs (n = 3). ns, not significant. *p ≤ 0.046, p-values were obtained from the unpaired two-tailed t test. P-value for CL is 0.046. Source data are provided as a Source Data file.