Characterization of the Role of PCRK1 in NORTIA-Mediated Pollen Tube Reception

Cell-to-cell communication is the driving force behind successful reproduction in flowering plants. Extensive extracellular communication events occur between the male and female gametophytes during pollen tube reception to facilitate successful fertilization. These signaling events culminate into a product of great importance for both animals and plants: the seed. In this study, the pathogen defense regulator PATTERN-TRIGGERED IMMUNITY COMPROMISED RECEPTOR-LIKE CYTOPLASMIC KINASE 1 (PCRK1) was identified to function in pollen tube reception from both the male and female gametophytes in the flowering plant Arabidopsis thaliana using a forward genetic screen. A knockout of pcrk1 suppresses the pollen tube overgrowth phenotype leading to infertility in nortia mutants. In addition, pcrk1 pollen affected the pollen tube overgrowth phenotypes of pollen tube reception mutants feronia and turan. Shared molecular components of pollen tube reception and pathogen invasion have been reported. This study reveals another link between pathogen defense and pollen tube reception. By studying the links between fertility and disease in plants, we may be able to uncover potential trade-offs with fertility when breeding for pathogen resistance.