TRANSPORTIN1 coordinates plant immune activation by mediating nuclear import of ADR1 helper NLRs

Plant NLR immune receptors can undergo dynamic changes in subcellular localization upon effector recognition. The Arabidopsis ADR1 helper NLRs mainly act at the plasma membrane (PM) in a phospholipid-dependent manner. Whether ADR1s display nuclear translocation and how ADR1s subcellular partitioning influences their immune function remains unknown. Here, we show that ADR1s relocate from the PM to the nucleus after TNL activation and identified TRANSPORTIN1 (TRN1) as a specific nuclear transport receptor that mediates nuclear import of ADR1s through direct binding, thus enabling the formation of TNL-induced EDS1-PAD4-ADR1s complex in the nucleus. Interestingly, TRN1 suppresses the autoactivity of ADR1s through compromising their PM localization and oligomerization. Nucleus-localized ADR1s restrict their autoactivation capacity but the nuclear pool of ADR1s is required for TNL-activated transcriptional reprogramming and disease resistance. Thus, TRN1-mediated nuclear import of ADR1s coordinates the PM and as-yet-undiscovered nuclear activities of ADR1s, thus enabling plants to mount a complete immune response.