Arabidopsis RCD1 coordinates chloroplast and mitochondrial functions through interaction with ANAC transcription factors
Reactive oxygen species (ROS)-dependent signaling pathways from chloroplasts and mitochondria merge at the nuclear protein RADICAL-INDUCED CELL DEATH1 (RCD1). RCD1 interacts in vivo and suppresses the activity of the transcription factors ANAC013 and ANAC017, which mediate a ROS-related retrograde signal originating from mitochondrial complex III. Inactivation of RCD1 leads to increased expression of mitochondrial dysfunction stimulon (MDS) genes regulated by ANAC013 and ANAC017. Accumulating MDS gene products, including alternative oxidases (AOXs), affect redox status of the chloroplasts, leading to changes in chloroplast ROS processing and increased protection of photosynthetic apparatus. ROS alter the abundance, thiol redox state and oligomerization of the RCD1 protein in vivo, providing feedback control on its function. RCD1-dependent regulation is linked to chloroplast signaling by 3'-phosphoadenosine 5'-phosphate (PAP). Thus, RCD1 integrates organellar signaling from chloroplasts and mitochondria to establish transcriptional control over the metabolic processes in both organelles.
The atomic coordinates and structural restraints for the C-terminal domain of RCD1 have been deposited in the Protein Data Bank with the accession code 5N9Q.
1H, 13C and 15N NMR chemical shift assignments of A. thaliana RCD1 RSTProtein Data Bank Japan, 5N9Q.
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Article and author information
- Jaakko Kangasjarvi
- Jarkko Salojärvi
- Eva-Mari Aro
- Michael Wrzaczek
- Jaakko Kangasjarvi
Fonds Wetenschappelijk Onderzoek
- Brecht Wybouw
- Bert De Rybel
- Frank van Breusegem
- Fayezeh Aarabi
- Alisdair R Fernie
Horizon 2020 Framework Programme
- Saleh Alseekh
- Alisdair R Fernie
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Christian S Hardtke, University of Lausanne, Switzerland
- Received: November 8, 2018
- Accepted: February 14, 2019
- Accepted Manuscript published: February 15, 2019 (version 1)
- Version of Record published: March 12, 2019 (version 2)
© 2019, Shapiguzov et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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