Matsumura, M. | bioRxiv Science

bioRxiv2023

Histone methyltransferase SUV39H1 regulates the Golgi complex via the nuclear envelope-spanning LINC complex

Cell motility is related to the higher-order structure of chromatin. Stimuli that induce cell migration change chromatin organization; such stimuli include elevated histone H3 lysine 9 trimethylation (H3K9me3). We previously showed that depletion of histone H3 lysine 9 methyltransferase, SUV39H1, suppresses directional cell migration. However, the molecular mechanism underlying this association between chromatin and cell migration remains elusive. The Golgi apparatus is a cell organelle essential for cell motility. In this study, we show that loss of H3K9 methyltransferase SUV39H1 but not SETDB1 or SETDB2 causes dispersion of the Golgi apparatus throughout the cytoplasm. The Golgi dispersion triggered by SUV39H1 depletion is independent of transcription, centrosomes, and microtubule organization, but is suppressed by depletion of any of the following three proteins: LINC complex components SUN2, nesprin-2, or microtubule plus-end-directed kinesin-like protein KIF20A. In addition, SUN2 is closely localized to H3K9me3, and SUV39H1 affects the mobility of SUN2 in the nuclear envelope. Further, inhibition of cell motility caused by SUV39H1 depletion is restored by suppression of SUN2, nesprin-2, or KIF20A. In summary, these results show the functional association between chromatin organization and cell motility via the Golgi organization regulated by the LINC complex.

cell biology↗

bioRxiv2021

Mechanosensory trichome cells evoke a mechanical stimuli-induced immune response in plants

Perception of pathogen-derived ligands by corresponding host receptors is a pivotal strategy in eukaryotic innate immunity. In plants, this is complemented by circadian anticipation of infection timing, promoting basal resistance even in the absence of pathogen threat. Here, we report that trichomes, hair-like structures on the epidermis, directly sense external mechanical forces caused by raindrops to anticipate waterborne infections in Arabidopsis thaliana. Exposure of leaf surfaces to mechanical stimuli initiates the concentric propagation of intercellular calcium waves away from trichomes to induce defence-related genes. Propagating calcium waves enable effective immunity against pathogenic microbes through the calmodulin-binding transcription activator 3 (CAMTA3) and mitogen-activated protein kinases. We propose a novel layer of plant immunity in which trichomes function as mechanosensory cells to detect potential risks.

plant biology↗