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The nuclear pore complex (NPC), the sole exchange channel between the nucleus and cytoplasm, is composed of several subcomplexes, among which the central barrier determines the permeability/selectivity of the NPC to dominate the nucleocytoplasmic trafficking essential for many important signaling events in yeast and mammals. How plant NPC central barrier controls selective transport is a crucial question remaining to be elucidated. In this study, we uncovered that phase separation of the central barrier is critical for the permeability and selectivity of plant NPC in the regulation of various biotic stresses. Phenotypic assays of nup62 mutants and complementary lines showed that NUP62 positively regulates plant defense against Botrytis cinerea , one of the world's most disastrous plant pathogens. Furthermore, in vivo imaging and in vitro biochemical evidence revealed that plant NPC central barrier undergoes phase separation to regulate selective nucleocytoplasmic transport of immune regulators, as exemplified by MPK3, essential for plant resistance to B. cinerea. Moreover, genetic analysis demonstrated that NPC phase separation plays an important role in plant defense against fungal and bacterial infection as well as insect attack. These findings reveal that phase separation of the NPC central barrier serves as an important mechanism to mediate nucleocytoplasmic transport of immune regulators and activate plant defense against a broad range of biotic stresses. The plant NPC central barrier undergoes phase separation to facilitate selective nucleocytoplasmic transport of immune regulators, including MPK3, critical for plant resistance to Botrytis cinerea. Such NPC central barrier phase separation-regulated nucleocytoplasmic transport is essential for plants to defend against pathogens and insects. Phase separation of the NPC central barrier serves as an important mechanism to mediate nucleocytoplasmic transport of immune regulators and regulate plant defense against a broad range of biotic stresses. [ABSTRACT FROM AUTHOR]

Phytohormones integrate external environmental and developmental signals with internal cellular responses for plant survival and multiplication in changing surroundings. Jasmonate (JA), which might originate from prokaryotes and benefit plant terrestrial adaptation, is a vital phytohormone that regulates diverse developmental processes and defense responses against various environmental stresses. In this review, we first provide an overview of ligand–receptor binding techniques used for the characterization of phytohormone–receptor interactions, then introduce the identification of the receptor COI1 and active JA molecules, and finally summarize recent advances on the regulation of JA perception and its evolution. Mechanisms of hormone perceptionis a topic of extraordinary significance, and perception of the hormone jasmonate (JA) is essential for plant defense and growth. This review highlights the methodology of ligand–receptor binding techniques and the interaction between bioactive JA and its receptor COI1. Recent advances on the regulation of JA perception and its evolution are also discussed. [ABSTRACT FROM AUTHOR]

Growth and immunity are opposing processes that compete for cellular resources, and proper resource allocation is crucial for plant survival. BSK1 plays a key role in the regulation of both growth and immunity by associating with BRI1 and FLS2, respectively. However, it remains unclear how two antagonistic signals co-opt BSK1 to induce signal-specific activation. Here we show that the dynamic spatial reorganization of BSK1 within the plasma membrane underlies the mechanism of signal-specific activation for growth or immunity. Resting BSK1 localizes to membrane rafts as complexes. Unlike BSK1-associated FLS2 and BRI1, flg22 or exogenous brassinosteroid (BR) treatment did not decrease BSK1 levels at the plasma membrane (PM) but rather induced BSK1 multimerization and dissociation from FLS2/BSK1 or BRI1/BSK1, respectively. Moreover, flg22-activated BSK1 translocated from membrane rafts to non-membrane-raft regions, whereas BR-activated BSK1 remained in membrane rafts. When applied together with flg22, BR suppressed various flg22-induced BSK1 activities such as BSK1 dissociation from FLS2/BSK1, BSK1 interaction with MAPKKK5, and BSK translocation together with MAPKKK5. Taken together, this study provides a unique insight into how the precise control of BSK1 spatiotemporal organization regulates the signaling specificity to balance plant growth and immunity. By using single-molecule techniques and biochemical approaches, this study demonstrates that the precise control of BSK1 spatiotemporal organization plays a pivotal role in fine-tuning the growth–defense trade-off between BRI1- and FLS2-mediated signaling. [ABSTRACT FROM AUTHOR]