Extended Data Fig. 2: Appressorial developmental processes prior to penetration are not affected by SPS1 deletion.
a, Superoxide detection by nitrotetrazolium blue chloride (NBT) staining shows Δsps1 appressoria generated reactive oxygen species (ROS) at the appressorial cell wall like WT. Samples were stained with 0.3 mM NBT at 24 h.p.i. for one hour before imaging. Images are representative of three experiments performed on plastic cover slips. b, Live-cell imaging of detached rice leaf sheaths by bright field microscopy shows unmelanized patches covering the pore at the base of both WT and Δsps1 appressoria. Scale bar is 10 μm. Images are representative of three experiments. c, Δsps1 appressoria on cellophane were dislodged at 24 h.p.i. by sonication for 30 min. In this example, the liberated appressorium has been flipped upside down, revealing a perfectly formed appressorial pore. Scale bar is 5 μm. d, Penetration rates of Δsps1 and WT appressoria at 24 h.p.i. after treatment with 2.5 mM spermine at the indicated time points. Values are the mean penetration rates determined for n=50 appressoria, repeated in triplicate. Bars are standard deviation. Significant differences of the means comparing WT and Δsps1 at a given treatment are denoted by different lowercase letters (two-way ANOVA, F2, 12 = 1126, p < 0.0001). Significant differences of the means within WT (one-way ANOVA, F2, 6 = 1261, p < 0.0001) or within Δsps1 (one-way ANOVA, F2, 6 = 1.00, p = 0.42) at different treatments are denoted by different uppercase letters.
