Fig. 3.

Plant responses to bacterial colonisation. Leaf-colonising bacteria elicit local and systemic responses. As shown on the left-hand side, a cell type-specific response to prevent bacteria from entering the apoplast is stomatal closure. As shown on the right-hand side, plants perceive bacteria via receptors localised in the plasma membrane (A, B, C, D), which recognise microbe-associated molecular patterns (depicted by hexagons, ovals and stars around the bacterium). Downstream signaling of these receptors is integrated in a highly interconnected immune signaling network. Integration of varying receptor inputs leads to specific immune outputs (α, β, γ).