About this Research Topic
Plants are and have been consistently challenged by different pests and pathogens, including fungi, bacteria, and viruses, during their whole life cycle as well as throughout their evolutionary history. To combat the threats due to pests and pathogens, plants have evolved a sophisticated two-layer defense system. The first layer immune system, termed as pathogen-associated molecular patterns (PAMPs)-triggered immunity (PTI), recognizes PAMPs of pathogens by cell surface-localized receptors. The second immune system usually detects effectors released by pathogens through intracellular receptors and therefore is referred to as effector-triggered immunity (ETI).
The genes encoding both surface-localized and intracellular immune receptors compose the key part of the plant disease resistance; hence, they are called disease resistance genes or R-genes. Since the cloning of the first R-gene was published in 1992, over 300 R-genes have been isolated. Our understanding of the functional mechanisms of R-genes has also extended from one simple “gene-for-gene” model to nine distinct different mechanisms. Among all types of identified R-genes, the nucleotide binding site-leucine-rich repeat (NBS-LRR) genes represent the largest family, which accounts for over 60% of the cloned R-genes. In the past 20 years, there has been a tremendous increase in the studies focused on the origin and evolution of the NBS-LRR R-genes. This includes revelation on the origin and evolution of both plant NBS-LRRs and pathogen effectors, as well as their evolutionary “arms race”. Maintaining a balance between benefit and potential fitness cost of R-genes is extremely important to plants. Regulatory roles played by methylation, miRNA and phasiRNA on R-gene expressions have been reported.
With the development of technologies and tools for epigenomics, transcriptomics, and proteomics, it is expected that many more novel insights into the evolutionary and mechanistic understanding of plant immune system would emerge rapidly. Therefore, this Research Topic will focus on articles that integrate rigorous bioinformatics and experimental investigations addressing the evolution and functional mechanism of plant disease resistance. We welcome original research, review, perspective, and opinion articles.
Keywords: plant disease resistance, evolution, diversification, molecular mechanism, regulation mechanism
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.