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Inze, D.

Publications and source records attributed to Inze, D..

2 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

Ubiquitylation activates a peptidase that promotes cleavage and destabilization of its activating E3 ligases and diverse growth regulatory proteins to limit cell proliferation in Arabidopsis

The characteristic shapes and sizes of organs are established by cell proliferation patterns and final cell sizes, but the underlying molecular mechanisms coordinating these are poorly understood. Here we characterize a ubiquitin-activated peptidase called DA1 that limits the duration of cell proliferation during organ growth in Arabidopsis thaliana. The peptidase is activated by two RING E3 ligases, BB and DA2, which are subsequently cleaved by the activated peptidase and destabilized. In the case of BB, cleavage leads to destabilization by the RING E3 ligase PRT1 of the N-end rule pathway. DA1 peptidase activity also cleaves the de-ubiquitylase UBP15, which promotes cell proliferation, and the transcription factors TCP15 and TCP22, which promote cell proliferation proliferation and repress endoreduplication. We propose that DA1 peptidase activity regulates the duration of cell proliferation and the transition to endoreduplication and differentiation during organ formation in plants by coordinating the destabilization of regulatory proteins.

plant biology