The study cloned the resistance genes Rmo2 and Rwt7 from barley and wheat, revealing them as orthologous tandem kinase proteins (TKPs) with an N‑terminal heavy metal‑associated (HMA) domain. Domain‑swapping experiments indicated that the HMA domain dictates effector specificity, supporting a model of TKP diversification into paralogs and orthologs that recognize distinct pathogen effectors.

The study reveals that barley and wheat tandem kinase proteins (TKPs) Rmo2 and Rwt7 detect distinct blast fungus effectors through integrated HMA domains, employing different protein interfaces with nanomolar affinity. Structural analysis identified key interface residues that govern effector recognition, enabling the engineering of TKPs with dual specificity, thereby demonstrating the programmability of HMA domains for crop disease resistance.

The authors used a bottom‑up thermodynamic modelling framework to investigate how plants decode calcium signals, starting from Ca2+ binding to EF‑hand proteins and extending to higher‑order decoding modules. They identified six universal Ca2+-decoding modules that can explain variations in calcium sensitivity among kinases and provide a theoretical basis for interpreting calcium signal amplitude and frequency in plant cells.

The study reveals that the rice blast fungus effector AVR-Pia targets four rice HMA domain‑containing proteins (HIPPs and HPPs), interacting with them both in vitro and in planta with varying affinities. The crystal structure of AVR‑Pia bound to the OsHPP09 HMA domain elucidates the binding interface, and a single point mutation in OsHPP09 abolishes binding, highlighting potential for engineering HMA domains to evade effector recognition.