Figure 3. 3D model of callose/cellulose interaction at the site of attempted fungal penetration.

3D model represents the formation of callose deposits, callose/cellulose polymer networks, and superficial callose layers at sites of attempted fungal penetration in (a), A. thaliana wild-type and (b), penetration-resistant PMR4-overexpressing epidermal leaf cells at 6 h post-inoculation with powdery mildew. Blue colours: callose ((1,3)-β-glucan), red colours: cellulose ((1,4)-β-glucan), grey colours: fungal structures (hyphae and conidium). Scale bars = 2 μm.