TY - JOUR A1 - Park, Misoon A1 - Krause, Cornelia A1 - Karnahl, Matthias A1 - Reichardt, Ilka A1 - El Kasmi, Farid A1 - Mayer, Ulrike A1 - Stierhof, York-Dieter A1 - Hiller, Ulrike A1 - Strompen, Georg A1 - Bayer, Martin A1 - Kientz, Marika A1 - Sato, Masa H. A1 - Nishimura, Marc T. A1 - Dangl, Jeffery L. A1 - Sanderfoot, Anton A. A1 - Jürgens, Gerd T1 - Concerted Action of Evolutionarily Ancient and Novel SNARE Complexes in Flowering-Plant Cytokinesis JF - Developmental cell N2 - Membrane vesicles delivered to the cell-division plane fuse with one another to form the partitioning membrane during plant cytokinesis, starting in the cell center. In Arabidopsis, this requires SNARE complexes involving the cytokinesis-specific Qa-SNARE KNOLLE. However, cytokinesis still occurs in knolle mutant embryos, suggesting contributions from KNOLLE-independent SNARE complexes. Here we show that Qa-SNARE SYP132, having counterparts in lower plants, functionally overlaps with the flowering plant-specific KNOLLE. SYP132 mutation causes cytokinesis defects, knolle syp132 double mutants consist of only one or a few multi-nucleate cells, and SYP132 has the same SNARE partners as KNOLLE. SYP132 and KNOLLE also have non-overlapping functions in secretion and in cellularization of the embryo-nourishing endosperm resulting from double fertilization unique to flowering plants. Evolutionarily ancient non-specialized SNARE complexes originating in algae were thus amended by the appearance of cytokinesis-specific SNARE complexes, meeting the high demand for membrane-fusion capacity during endosperm cellularization in angiosperms. Y1 - 2018 U6 - https://doi.org/10.1016/j.devcel.2017.12.027 SN - 1534-5807 SN - 1878-1551 VL - 44 IS - 4 SP - 500 EP - + PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - Frescatada-Rosa, Marcia A1 - Stanislas, Thomas A1 - Backues, Steven K. A1 - Reichardt, Ilka A1 - Men, Shuzhen A1 - Boutte, Yohann A1 - Juergens, Gerd A1 - Moritz, Thomas A1 - Bednarek, Sebastian York A1 - Grebe, Markus T1 - High lipid order of Arabidopsis cell-plate membranes mediated by sterol and Dynamin-Related Protein 1A function JF - The plant journal N2 - Membranes of eukaryotic cells contain high lipid-order sterol-rich domains that are thought to mediate temporal and spatial organization of cellular processes. Sterols are crucial for execution of cytokinesis, the last stage of cell division, in diverse eukaryotes. The cell plate of higher-plant cells is the membrane structure that separates daughter cells during somatic cytokinesis. Cell-plate formation in Arabidopsis relies on sterol- and DYNAMIN-RELATED PROTEIN1A (DRP1A)-dependent endocytosis. However, functional relationships between lipid membrane order or lipid packing and endocytic machinery components during eukaryotic cytokinesis have not been elucidated. Using ratiometric live imaging of lipid order-sensitive fluorescent probes, we show that the cell plate of Arabidopsis thaliana represents a dynamic, high lipid-order membrane domain. The cell-plate lipid order was found to be sensitive to pharmacological and genetic alterations of sterol composition. Sterols co-localize with DRP1A at the cell plate, and DRP1A accumulates in detergent-resistant membrane fractions. Modifications of sterol concentration or composition reduce cell-plate membrane order and affect DRP1A localization. Strikingly, DRP1A function itself is essential for high lipid order at the cell plate. Our findings provide evidence that the cell plate represents a high lipid-order domain, and pave the way to explore potential feedback between lipid order and function of dynamin-related proteins during cytokinesis. KW - membrane order KW - sterol KW - cytokinesis KW - DRP1A KW - Arabidopsis Y1 - 2014 U6 - https://doi.org/10.1111/tpj.12674 SN - 0960-7412 SN - 1365-313X VL - 80 IS - 5 SP - 745 EP - 757 PB - Wiley-Blackwell CY - Hoboken ER -