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van de Cotte, B.

Publications and source records attributed to van de Cotte, B..

3 recordsLinked to original sources

Early mannitol-triggered changes in the Arabidopsis leaf (phospho)proteome

Drought is one of the most detrimental environmental stresses to which plants are exposed. Especially mild drought is relevant to agriculture and significantly affects plant growth and development. In plant research, mannitol is often used to mimic drought stress and study the underlying responses. In growing leaf tissue of plants exposed to mannitol-induced stress, a highly-interconnected gene regulatory network is induced. However, early signaling and associated protein phosphorylation events that likely precede part of these transcriptional changes are largely unknown. Here, we performed a full proteome and phosphoproteome analysis on growing leaf tissue of Arabidopsis plants exposed to mild mannitol-induced stress and captured the fast (within the first half hour) events associated with this stress. Based on this in-depth data analysis, 167 and 172 differentially regulated proteins and phosphorylated sites were found back, respectively. Additionally, we identified H(+)-ATPASE 2 (AHA2) and CYSTEINE-RICH REPEAT SECRETORY PROTEIN 38 (CRRSP38) as novel regulators of shoot growth under osmotic stress.\n\nHighlightWe captured early changes in the Arabidopsis leaf proteome and phosphoproteome upon mild mannitol stress and identified AHA2 and CRRSP38 as novel regulators of shoot growth under osmotic stress

plant biology

Temperature-induced changes in wheat phosphoproteome reveal temperature-regulated interconversion of phosphoforms

Wheat (Triticum ssp.) is one of the most important human food sources. However, this crop is very sensitive to temperature changes. Specifically, processes during wheat leaf, flower and seed development and photosynthesis, which all contribute to the yield of this crop, are affected by high temperature. While this has to some extent been investigated on physiological, developmental and molecular levels, very little is known about early signalling events associated with an increase in temperature. Phosphorylation-mediated signalling mechanisms, which are quick and dynamic, are associated with plant growth and development, also under abiotic stress conditions. Therefore, we probed the impact of a short-term increase in temperature on the wheat leaf and spikelet phosphoproteome. The resulting data set provides the scientific community with a first large-scale plant phosphoproteome under the control of higher ambient temperature, which will be valuable for future studies. Our analyses also revealed a core set of common proteins between leaf and spikelet, suggesting some level of conserved regulatory mechanisms. Furthermore, we observed temperature-regulated interconversion of phosphoforms, which likely impacts protein activity.

plant biology

The expa1-1 mutant reveals a new biophysical lateral root organogenesis checkpoint

In plants, post-embryonic formation of new organs helps shape the adult organism. This requires the tight regulation of when and where a new organ is formed, and a coordination of the underlying cell divisions. To build a root system, new lateral roots are continuously developing, and this process requires asymmetric cell division in adjacent pericycle cells. Characterization of an expansin a1 (expa1) mutant has revealed a novel checkpoint during lateral root formation. Specifically, a minimal pericycle width was found to be necessary and sufficient to trigger asymmetric pericycle cell divisions during auxin-driven lateral root formation. We conclude that a localized radial expansion of adjacent pericycle cells is required to position the asymmetric cell divisions and generate a core of small daughter cells, which is a prerequisite for lateral root organogenesis.\n\nSIGNFICANCE STATEMENTOrgan formation is an essential process in plants and animals, driven by cell division and cell identity establishment. Root branching, where lateral roots form along the primary root axis, increases the root system and aids capture of water and nutrients. We have discovered that tight control of cell width is necessary to co-ordinate asymmetric cell divisions in cells that give rise to a new lateral root organ. While biomechanical processes have been shown to play a role in plant organogenesis, including lateral root formation, our data give new mechanistic insights into the cell size checkpoint during lateral root initiation.

plant biology