14-3-3 Proteins and Other Candidates form Protein-Protein Interactions with the Cytosolic C-terminal End of SOS1 Affecting Its Transport Activity
- The plasma membrane transporter SOS1 (SALT-OVERLY SENSITIVE1) is vital for plant survival under salt stress. SOS1 activity is tightly regulated, but little is known about the underlying mechanism. SOS1 contains a cytosolic, autoinhibitory C-terminal tail (abbreviated as SOS1 C-term), which is targeted by the protein kinase SOS2 to trigger its transport activity. Here, to identify additional binding proteins that regulate SOS1 activity, we synthesized the SOS1 C-term domain and used it as bait to probe Arabidopsis thaliana cell extracts. Several 14-3-3 proteins, which function in plant salt tolerance, specifically bound to and interacted with the SOS1 C-term. Compared to wild-type plants, when exposed to salt stress, Arabidopsis plants overexpressing SOS1 C-term showed improved salt tolerance, significantly reduced Na+ accumulation in leaves, reduced induction of the salt-responsive gene WRKY25, decreased soluble sugar, starch, and proline levels, less impaired inflorescence formation and increased biomass. It appears that overexpressing SOS1 C-term leads to the sequestration of inhibitory 14-3-3 proteins, allowing SOS1 to be more readily activated and leading to increased salt tolerance. We propose that the SOS1 C-term binds to previously unknown proteins such as 14-3-3 isoforms, thereby regulating salt tolerance. This finding uncovers another regulatory layer of the plant salt tolerance program
Verfasser*innenangaben: | Duscha Kerstin, Cristina Martins RodriguesORCiD, Maria Müller, Ruth Wartenberg, Larry Fliegel, Joachim W. Deitmer, Martin Jung, Richard Zimmermann, Ekkehard NeuhausORCiD |
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URN: | urn:nbn:de:hbz:386-kluedo-61602 |
ISSN: | 1422-0067 |
Titel des übergeordneten Werkes (Englisch): | International Journal of Molecular Sciences |
Verlag: | MDPI |
Dokumentart: | Wissenschaftlicher Artikel |
Sprache der Veröffentlichung: | Englisch |
Datum der Veröffentlichung (online): | 08.05.2020 |
Jahr der Erstveröffentlichung: | 2020 |
Veröffentlichende Institution: | Technische Universität Kaiserslautern |
Datum der Publikation (Server): | 04.12.2020 |
Ausgabe / Heft: | 21(9) |
Seitenzahl: | 18 |
Quelle: | https://www.mdpi.com/1422-0067/21/9/3334 |
Fachbereiche / Organisatorische Einheiten: | Kaiserslautern - Fachbereich Biologie |
DDC-Sachgruppen: | 5 Naturwissenschaften und Mathematik / 570 Biowissenschaften, Biologie |
Sammlungen: | Open-Access-Publikationsfonds |
Lizenz (Deutsch): | Zweitveröffentlichung |