Nucleotide-binding domain–leucine-rich repeat-type immune receptors (NLRs) protect plants against pathogenic microbes through intracellular detection of effector proteins. However, this comes at a cost, as NLRs can also induce detrimental autoimmunity in genetic interactions with foreign alleles. This may occur when independently evolved genomes are combined in inter- or intraspecific crosses, or when foreign alleles are introduced by mutagenesis or transgenesis. Most autoimmunity-inducing NLRs are encoded within highly variable NLR gene clusters with no known immune functions, which were termed autoimmune risk loci. Whether risk NLRs differ from sensor NLRs operating in natural pathogen resistance and how risk NLRs are activated in autoimmunity is unknown. Here, we analyzed the DANGEROUS MIX2 risk locus, a major autoimmunity hotspot in Arabidopsis thaliana . By gene editing and heterologous expression, we show that a single gene, DM2h , is necessary and sufficient for autoimmune induction in three independent cases of autoimmunity in accession Landsberg erecta . We focus on autoimmunity provoked by an EDS1-YFP ^NLS fusion protein to functionally characterize DM2h and determine features of EDS1-YFP ^NLS activating the immune receptor. Our data suggest that risk NLRs function reminiscent of sensor NLRs, while autoimmunity-inducing properties of EDS1-YFP ^NLS are in this context unrelated to the protein’s functions as immune regulator. We propose that autoimmunity may, at least in some cases, be caused by spurious, stochastic interactions of foreign alleles with co-incidentally matching risk NLRs.

Apricots originated from China, Central Asia and the Near East and arrived in Anatolia, and particularly in their second homeland of Malatya province in Turkey. Apricots are outstanding summer fruits, with their beautiful attractive colour, delicious sweet taste, aroma and high vitamin and mineral content. In the current study, a total of 259 apricot genotypes from different geographical origins in Turkey were used. Significant variations were detected in fruit firmness (FF), fruit flesh color (FFC), flowering time (FT), and soluble solid content (SSC). A total of 11,532 SNPs based on DArT were developed and used in the analyses of population structure and association mapping (AM). According to the STRUCTURE (v.2.2) analysis, the apricot genotypes were divided into three groups. The mixed linear model with Q and K matrixes were used to detect the associations between the SNPs and four traits. A total of 131 SNPs were associated with FF, FFC, and SSC. The results demonstrated that AM had high potential of revealing the markers associated with economically important traits in apricot.