FUNCTIONAL CHARACTERIZATION OF Xa10-LIKE GENES IN RICE CULTIVAR NIPPONBARE AND GENETIC ENGINEERING OF PEPPER Bs4C GENES IN RICE FOR DISEASE RESISTANCE TO BACTERIAL BLIGHT

Abstract

Firstly, the function of two Xa10-like genes (Xa10-N1 and Xa10-N2) in the rice cultivar Nipponbare was characterized. Artificially designed TAL effector (dTALE)-mediated induction of Xa10-N1 or Xa10-N2 triggers disease resistance responses to bacterial blight in rice. Both XA10-N1 and XA10-N2 induce cell death in Nicotiana benthamiana, locate to the endoplasmic reticulum (ER) membrane, and cause calcium depletion from the ER lumen to cytosol. Secondly, Xa10 promoter activity induced by AvrXa10 was evaluated through generating GUS reporter lines with Xa10 promoters and avrXa10 expressed in rice. Finally, pepper Bs4C genes were genetically engineered into rice plants for disease resistance to bacterial blight. Driven by the Xa10 promoter, the coding sequences of Bs4C genes (CaBs4C, CpBs4C-R and CpBs4C-S) confer race-specific resistance to X. oryzae pv. oryzae strains harbouring the TAL effector gene avrXa10.