The role of Phytopthora parasitica PpRxLR1 and PpRxLR6 effector proteins in plant immunity

<p>Supplementary data presenting the role of<em> P. parasitica</em> PpRxLR1 and PpRxLR6 in plant immunity. The <em>in silico </em>analyses revealed that <em>P.  parasitica</em> INRA 310 secrete 71 conserved RxLR effectors. Among the 71 CRE, PpRxLR1 and PpRxLR6 effector proteins were selected for further functional characterization. Inoculation of <em>Nicotiana benthamiana</em> leaves with zoospores indicated that the life cycle of <em>P. parasitica</em> switches from asymptomatic to symptomatic phase. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) analyses of the inoculated leaves showed that parasitica PpRxLR1 and PpRxLR6 are expressed during the biotrophic phase, suggesting their importance in virulence. Findings from <em>Agrobacterium tumefacient</em>-mediated transient expression of PpRxLR1 and PpRxLR6  in <em>N. benthamiana</em> revealed potential mechanisms of<em> P. parasitica</em> PpRxLR1 and PpRxLR6 in promoting disease development, this includes inducing reactive oxygen species as well as callose deposition. In addition, RT-PCR  analyses revealed that PpRxLR1 and PpRxLR6 induce phytohormones (SA, ET, JA) and MAPKs (MPK3 and  MPK6). These data indicate that both PpRxLR1 and PpRxLR6 are important virulence factors of<em> P. parasitica.</em> </p>