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Corrion, A.

Publications and source records attributed to Corrion, A..

2 recordsLinked to original sources
bioRxiv2025

Actin Depolymerization Factors (ADFs) Moonlighting: Nuclear Immune Regulation by Interacting with WRKY Transcription Factors and Shaping the Transcriptome

Remodeling of the actin cytoskeleton is a critical process for plant immunity, essential for the transport, activation, and stabilization of immune-regulatory molecules and organelles. In this process, actin depolymerization factors (ADFs) function as key players through severing and depolymerizing actin microfilaments. However, recent evidence suggests that ADFs may possess non-canonical immune functions inside the nucleus, in addition to the canonic cytosolic role, a phenomenon not adequately explained by the traditional mechanistic model of ADF-actin dynamics. In this study, we demonstrate that Arabidopsis ADFs exhibit a moonlighting function in the nucleus, where they interact with transcriptional machinery to regulate the transcriptome during both the resting state and the immune responses. We show that ADF2/3/4 have redundant functions in defense against virulent and avirulent Pseudomonas syringae. Notably, it is nuclear - rather than cytosolic - ADFs that contribute to defense against P. syringae and mediate pro-immune transcription. Mechanistically, we demonstrate that nuclear ADFs interact with transcription factors, histone complexes, and other components of the transcriptional machinery. Specifically, ADF2/3/4 can form a complex with WRKY transcription factors, such as WRKY22/29/48, thereby directly regulating WRKY activity to shape the pro-immune transcriptome. In summary, our study reveals that ADFs moonlight as direct regulators of transcription factors, mediating a broad range of nuclear-cytoplasmic regulation in plant immunity and potentially other biological processes.

plant biology↗
bioRxiv2021

NDR1 and the Arabidopsis Plasma Membrane ATPase AHA5 are Required for Processes that Converge on Drought Tolerance and Immunity

NON-RACE-SPECIFIC DISEASE RISISTANCE1 (NDR1) is a key component of plant immune signaling, required for defense against the bacterial pathogen Pseudomonas syringae. Plant stress responses have overlapping molecular, physiological, and cell biology signatures, and given the central role of NDR1 during biotic stress perception and signaling, we hypothesized that NDR1 also functions in abiotic stress responses, including in a role that mediates signaling at the plasma membrane (PM) - cell wall (CW) continuum. Here, we demonstrate that NDR1 is required for the induction of drought stress responses in plants, a role that couples stress signaling in an abscisic acid-dependent manner. We show that NDR1 physically associates with the PM-localized H+-ATPases AHA1, AHA2, and AHA5 and is required for proper regulation of H+-ATPase activity and stomatal guard cell dynamics, providing a mechanistic function of NDR1 during drought responses. In the current study, we demonstrate that NDR1 functions in signaling processes associated with both biotic and abiotic stress response pathways, a function we hypothesize represents NDR1s role in the maintenance of cellular homeostasis during stress. We propose a role for NDR1 as a core transducer of signaling between cell membrane processes and intercellular stress response activation.

plant biology↗