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bioRxiv · 10.1101/2025.09.17.676730

Ca2+-dependent nanodomain enrichment is crucial for the perception of bacterial outer membrane vesicles in plants

Mondal, I.·Das, H.·Behera, S.
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Abstract

O_LIXanthomonas oryzae pv. oryzae (Xoo) releases OMVs; however, the role of Xoo-OMVs in Xoo-rice interaction has not yet been studied. We investigated the early signalling events underlying Xoo-OMV perception by rice to gain insight into early plant-pathogen interactions. C_LIO_LIWe observed that Xoo-OMVs are perceived by rice through a rapid and unique Ca2+ signal that is essential to evoke an immune response. By confocal imaging and proteomic analysis of the rice PM, we found that the Ca2+ signal is required for Xoo-OMV-induced nanodomain enrichment and for the aggregation of defence response-associated proteins in rice PM. C_LIO_LIThe differential assembly of proteins in the PM helps the plant defend itself against Xoo. In the absence of the early Ca2+ signal, Xoo-OMVs are not perceived by the plant, resulting in a compromised immune response. C_LIO_LICollectively, our study shows that Xoo-OMVs are recognised by rice via Ca2+ signal-induced nanodomain assembly leading to protein reorganisation in the PM to prepare the plant for an imminent pathogen invasion. C_LI

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Mondal, I., Das, H., Behera, S.. 2025-09-17. Ca2+-dependent nanodomain enrichment is crucial for the perception of bacterial outer membrane vesicles in plants. https://doi.org/10.1101/2025.09.17.676730

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