Overexpression of a rice eIF2β variant modulates leaf age-dependent resistance to pathogens in Arabidopsis thaliana

Plants display diverse resistance responses that are influenced by their age and the timing of pathogen exposure. In Arabidopsis thaliana (Arabidopsis), nonhost resistance (NHR) to Pyricularia oryzae varies with leaf age and the time of inoculation. While the circadian clock and photoperiod have been linked to the time-dependent regulation of NHR in Arabidopsis, the mechanism underlying leaf age-dependent NHR remains unclear. To identify key players in leaf age-dependent NHR to P. oryzae in Arabidopsis, we utilized rice-Full-length cDNA OvereXpressing (FOX) Arabidopsis lines and identified the rice eIF2/3 (eukaryotic translation initiation factor 2 beta subunit) variant (Os03g0333300-2). Overexpression of the rice eIF2/3 variant reduced NHR to P. oryzae and modulated host resistance (HR) to Colletotrichum higginsianum in Arabidopsis. The effect of Os03g0333300-2 expression on resistance is dependent on leaf age in Arabidopsis. These results suggest that overexpression of the rice eIF2/3 variant Os03g0333300-2 could contribute to defense responses in a leaf age-dependent manner in Arabidopsis. Our findings might suggest the involvement of the rice eIF2/3 variant in eIF2-dependent translation regulation of resistance response to pathogens in plants.