Figure 1.

Recognition of a pathogen by the plant and induction of active immune response. Pathogen-associated molecular patterns (PAMPs) are perceived by plant transmembrane pattern recognition receptors (PRRs), which induce signaling cascades and lead to PAMP triggered immunity (PTI). During pathogen attack, pathogens produce effectors molecules (Avr) to increase their pathogenicity into the host cells to suppress PTI and to interfere with hormonal balance. Plants having corresponding resistance (R) genes recognize effectors and activate immune responses (effector-triggered immunity, ETI). After recognition, it is triggered the transcription of the cascade of plant defense mechanisms, and the activation of genes to a robust and quick defense response is induced. ETI response may include altering chromatin configuration that further facilitates access by transcription factors (TFs). Adapted from [10].