Fig. 3. Host-dependent effect of mimicking MP phosphorylation on plasmodesmal permeability. (A and E) Fluorescently labeled dextran (10 kDa) microinjected alone into N.tabacum or N.benthamiana, respectively. (B and F) Wild-type MP mixed with 10 kDa fluorescently labeled dextran and microinjected into N.tabacum or N.benthamiana, respectively. (C and G) del 7 mixed with 10 kDa fluorescently labeled dextran and microinjected into N.tabacum or N.benthamiana, respectively. (D and H) sb-9 mixed with 10 kDa fluorescently labeled dextran and microinjected into N.tabacum or N.benthamiana, respectively. Intercellular distribution of the signal was visualized 25–45 min after injection. Arrows indicate injected cells. Magnification: 120×. Note that black spaces between cells represent intercellular air pockets characteristic for tobacco leaf mesophyll tissues (Waigmann et al., 1994).