Figure 2.

Illustration depicting the mechanistic basis of the establishment of immune memory in plants. Pathogen recognition by receptor-like kinases (RLKs), receptor-like proteins (RLPs) and intracellular NOD-like receptors (NLRs) leads to complex defence signalling and transcriptome reprogramming that induces epigenetic marks on the genome. These marks may be temporary or permanent, depending on the magnitude and frequency of the particular stress. Priming through SA and establishing SAR is a customary event for plant memory against biotic pathogens. In many cases, such biotic stress memories are transgenerational. TMD, transmembrane domain; HDM, histone demethylase; HMT, histone methyltransferase; HDAC, histone deacetylase; HAT, histone acetyltransferase; RBOH, respiratory burst oxidase; ROS, reactive oxygen species; CC/TIR, coiled-coil/toll-interleukin receptor; NBD, nucleotide-binding domain; TF, transcription factor; SA, salicylic acid; SAR, systemic acquired resistance.