Fig. 7

NLR-WRKY/AP2a domain shuffling involved inter-chromosomal copy-and-paste of the AP2 gene. a A clade in the phylogeny of NLR-ID proteins from Fig. 5 that includes wheat. A, B and D genome homoeologs from the same genetic position. New integration is evident from homologs with AP2 and a WRKY domains (highlighted by red boxes). Dots on the tree branches indicate a bootstrap support value ≥ 85%. E-value cut-off for presence of an ID domain, 0.001; a domain with e-value > 0.001 and ≤ 0.05 is shown as a gray rectangle. E-value cut-off for an LRR domain, 10.0. b An AP2/ERF family tree (left) showing two clades that contain an NLR acceptor ID protein (NLR-AP2a and NLR-AP2b, indicated in red). The protein sequences of these clades were re-aligned and the trees re-estimated (right) to confirm the identity of the donor protein, evident from high bootstrap support values. c Protein alignment cartoon of one of the AP2 donor proteins and the acceptor protein, NLR-AP2a. By contrast, the NLR acceptor protein homoeologs contain two WRKY domains in their C-terminal ends (d) summary model illustrating the inter-chromosomal duplication of an ID domain and subsequent movement into an NLR gene