Author
Underwood, William | |
SOMERVILLE, SHAUNA - University Of California |
Submitted to: Plant Signaling and Behavior
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/11/2017 Publication Date: 9/14/2017 Citation: Underwood, W., Somerville, S.C. 2017. Phosphorylation is required for the pathogen defense function of the Arabidopsis PEN3 ABC transporter. Plant Signaling and Behavior. 12(10):e1379644. https://doi.org/10.1080/15592324.2017.1379644. DOI: https://doi.org/10.1080/15592324.2017.1379644 Interpretive Summary: Plants resist diseases by detecting potentially pathogenic microorganisms and activating appropriate defense responses. When a microbial intruder is detected, a signal is processed through a series of steps that ultimately leads to activation of defense outputs at the appropriate level, time, and place. The events that link detection of disease-causing microorganisms with defense responses are poorly understood. In this study, we identified key regulatory events that control the activation of defense responses effective against powdery mildew fungi, which, as a group, are among the most prevalent pathogens of plants worldwide. These findings further our understanding of plant immune responses and may lead to novel strategies to combat destructive plant diseases. Technical Abstract: The Arabidopsis PEN3 ABC transporter accumulates at sites of pathogen detection, where it is involved in defense against multiple pathogens. Perception of PAMPs by pattern recognition receptors initiates recruitment of PEN3 and also leads to PEN3 phosphorylation at multiple amino acid residues. Whether PAMP-induced phosphorylation of PEN3 is important for its defense function or focal recruitment has not been addressed. In this study, we evaluated the role of PEN3 phosphorylation in modulating the localization and defense function of the transporter. We report that PEN3 phosphorylation is critical for its function in defense, but dispensable for recruitment to powdery mildew penetration sites. These results indicate that PAMP-induced phosphorylation of PEN3 may potentially activate the transport function or modulate substrate specificity. |