ALT Annotated flow diagram to illustrate how, in wheat, phosphorylation of the S-like RNase TaRNS4 mediated by the kinase TaRLK5 promotes its degradation of Puccinia striiformis f. sp. tritici RNA in the apoplast, enhancing resistance to stripe rust. Also shown: how TaRNS4 can hijack phosphatase TaPP2C10 to relieve its dephosphorylation of TaMAPK6, thereby activating MAPK-mediated immune responses.