Arabidopsis MSI1 is required for negative regulation of the response to drought stress.
Arabidopsis MSI1 has fundamental functions in plant development. MSI1 is a subunit of Polycomb group protein complexes and Chromatin assembly factor 1, and it interacts with the Retinoblastoma-related protein 1. Altered levels of MSI1 result in pleiotropic phenotypes, reflecting the complexity of MSI1 protein functions. In order to uncover additional functions of MSI1, we performed transcriptional profiling of wild-type and plants with highly reduced MSI1 levels (msi1-cs). Surprisingly, the known functions of MSI1 could only account for a minor part of the transcriptional changes in msi1-cs plants. One of the most striking unexpected observations was the up-regulation of a subset of ABA-responsive genes eliciting the response to drought and salt stress. We report that MSI1 can bind to the chromatin of the drought-inducible downstream target RD20 and suggest a new role for MSI1 in the negative regulation of the Arabidopsis drought-stress response.
Alexandre
Cristina
C
Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, CH-8092 Zurich, Switzerland.
Möller-Steinbach
Yvonne
Y
Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, CH-8092 Zurich, Switzerland.
Schönrock
Nicole
N
Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, CH-8092 Zurich, Switzerland; Brain and Mind Research Institute, University of Sydney, 100 Mallett St, Camperdown, NSW 2050, Australia.
Gruissem
Wilhelm
W
Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, CH-8092 Zurich, Switzerland.
Hennig
Lars
L
Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, CH-8092 Zurich, Switzerland; Department of Biology, ETH Zurich, LFW E17, CH-8092 Zurich, Switzerland. Electronic address: lars.hennig@ipw.biol.ethz.ch.
D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D019295:Computational Biology; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D015151:Immunoblotting; D011485:Protein Binding; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013312:Stress, Physiological / Q000235:genetics*
D029681:Arabidopsis Proteins; D002135:Calcium-Binding Proteins; D002843:Chromatin; C475821:MSI1 protein, Arabidopsis; C417972:RD20 protein, Arabidopsis