Rpivnt1 provides resistance through the mediation of a light responsive guardee in potato

The disease triangle describes the interrelationship among pathogen, host, and environment towards disease prevalence in the field. The mechanistic role of environment on NLR-mediated resistance was not known until now. Recently, a comprehensive work revealed that light controls late blight disease reaction in potato caused by the Irish famine pathogen. A specific R gene Rpivnt1 in potato showed dichotomous behavior in disease reaction due to the light-responsive alternate promoter selection of another host gene glycerate 3 kinase (GLYK) during its transcription. The full-length GLYK protein traps the pathogen effector AVRvnt1 into a recognition event which is later sensed by Rpivnt1 in the presence of light. In dark, the truncated GLYK protein devoid of its chloroplastic transit peptide could not able to recognize AVRvnt1 and thus resistance get compromised. A possible model for this event is proposed here for ease in understanding.