High allelic diversity in Arabidopsis NLRs is associated with distinct genomic features

作者：Chandler A. Sutherland, D. Prigozhin, J. G. Monroe, K. Krasileva · 发表于：EMBO Reports · 年份：2024 · DOI：10.1038/s44319-024-00122-9 · 被引用次数：14 · 研究领域：Medicine

Plants rely on Nucleotide-binding, Leucine-rich repeat Receptors (NLRs) for pathogen recognition. Highly variable NLRs (hvNLRs) show remarkable intraspecies diversity, while their low-variability paralogs (non-hvNLRs) are conserved between ecotypes. At a population level, hvNLRs provide new pathogen-recognition specificities, but the association between allelic diversity and genomic and epigenomic features has not been established. Our investigation of NLRs in Arabidopsis Col-0 has revealed that hvNLRs show higher expression, less gene body cytosine methylation, and closer proximity to transposable elements than non-hvNLRs. hvNLRs show elevated synonymous and nonsynonymous nucleotide diversity and are in chromatin states associated with an increased probability of mutation. Diversifying selection maintains variability at a subset of codons of hvNLRs, while purifying selection maintains conservation at non-hvNLRs. How these features are established and maintained, and whether they contribute to the observed diversity of hvNLRs is key to understanding the evolution of plant innate immune receptors. Rapid intraspecies diversification of Arabidopsis NLR immune receptors is associated with distinct genomic and epigenomic features. Both mutational likelihood and selection contribute to amino acid diversity at the pangenome level. Rapidly evolving, highly variable NLRs are more expressed, less methylated, and closer to transposable elements than their conserved paralogs. These genom...