Snf1-RELATED KINASE1-Controlled C/S-bZIP Signaling Activates Alternative Mitochondrial Metabolic Pathways to Ensure Plant Survival in Extended Darkness

Author(s)
Lorenzo Pedrotti, Christoph Weiste, Thomas Nägele, Elmar Wolf, Francesca Lorenzin, Katrin Dietrich, Andrea Mair, Wolfram Weckwerth, Markus Teige, Elena Baena-González, Wolfgang Dröge-Laser
Abstract

Sustaining energy homeostasis is of pivotal importance for all living organisms. InArabidopsis thaliana, evolutionarily conserved SnRK1 kinases (Snf1-RELATED KINASE1) control metabolic adaptation during low energy stress. To unravel starvation-induced transcriptional mechanisms, we performed transcriptome studies of inducible knockdown lines and found that S1-basic leucine zipper transcription factors (S1-bZIPs) control a defined subset of genes downstream of SnRK1. For example, S1-bZIPs coordinate the expression of genes involved in branched-chain amino acid catabolism, which constitutes an alternative mitochondrial respiratory pathway that is crucial for plant survival during starvation. Molecular analyses defined S1-bZIPs as SnRK1-dependent regulators that directly control transcription via binding to G-box promoter elements. Moreover, SnRK1 triggers phosphorylation of group C-bZIPs and the formation of C/S1-heterodimers and, thus, the recruitment of SnRK1 directly to target promoters. Subsequently, the C/S1-bZIP-SnRK1 complex interacts with the histone acetylation machinery to remodel chromatin and facilitate transcription. Taken together, this work reveals molecular mechanisms underlying how energy deprivation is transduced to reprogram gene expression, leading to metabolic adaptation upon stress.

Organisation(s)
Department of Ecogenomics and Systems Biology, Research Platform Vienna Metabolomics Center, Large-Instrument Facility for Mass Spectrometry in Life Sciences, Department of Biochemistry and Cell Biology
Journal
The Plant Cell
Volume
30
Pages
495-509
No. of pages
15
ISSN
1040-4651
DOI
https://doi.org/10.1105/tpc.17.00414
Publication date
02-2018
Publication status
Published
Peer reviewed
Yes
Austrian Fields of Science 2012
106031 Plant physiology, 106002 Biochemistry, 106057 Metabolomics
Portal url
https://ucris.univie.ac.at/portal/en/publications/snf1related-kinase1controlled-csbzip-signaling-activates-alternative-mitochondrial-metabolic-pathways-to-ensure-plant-survival-in-extended-darkness(066a875c-16dd-4e32-b061-bef36be3cfd8).html