The crystal structure of AVR-Pia in complex with the HMA domain of OsHPP09 revealed the molecular details of the binding interface

To understand the structural basis of the interaction between AVR-Pia and OsHPP09-HMA, we purified and crystallised the effector/HMA complex. Needle-like crystals were obtained in commercial screens and subsequent optimisation of conditions resulted in crystals suitable for diffraction studies.
As expected, OsHPP09-HMA adopts the well-characterised HMA domain fold, consisting of a four-stranded antiparallel β-sheet and two ⍺-helices arranged with β⍺ββ⍺β topology.