PbERF2-like interacts with PbNPR1 while enhancing the resistance of pear to Alternaria alternata

Abstract

As a typical regulatory protein, transcription factors (TFs) participate in plant defense regulation by sensing stress signals and guiding the expression of downstream defense genes. Analyzing the function of transcription factors in interaction with other proteins is important to elucidate the role of these transcription factors in different signaling cascades. Here, we found that the expression of the ERF subfamily member PbERF2-like was highly induced by A. alternata infection. PbERF2-like encodes a nuclear localization protein, which positively regulated pear resistance to Alternaria leaf spot (ALS). Protein interaction assays revealed that PbERF2-like physically interacts with PbNPR1 to form a protein complex. Additionally, stable overexpression in pear calli demonstrated that PbNPR1 plays a positive role in pear resistance to A. alternata. We further discover that PbERF2-like and PbNPR1 synergistically activate PR genes and plant defenses via SA signaling. Taken together, our study revealed that PbERF2-like and PbNPR1 interaction cooperatively activates SA signaling and pathogen resistances.