UNIVERSITÄTSBIBLIOTHEK

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

Download full text files

Export metadata

Metadaten
Author:Duscha Kerstin, Cristina Martins RodriguesORCiD, Maria Müller, Ruth Wartenberg, Larry Fliegel, Joachim W. Deitmer, Martin Jung, Richard Zimmermann, Ekkehard NeuhausORCiD
URN (permanent link):urn:nbn:de:hbz:386-kluedo-61602
ISSN:1422-0067
Parent Title (English):International Journal of Molecular Sciences
Publisher:MDPI
Document Type:Article
Language of publication:English
Publication Date:2020/05/08
Year of Publication:2020
Publishing Institute:Technische Universität Kaiserslautern
Date of the Publication (Server):2020/12/04
Issue:21(9)
Number of page:18
Source:https://www.mdpi.com/1422-0067/21/9/3334
Faculties / Organisational entities:Fachbereich Biologie
DDC-Cassification:5 Naturwissenschaften und Mathematik / 570 Biowissenschaften, Biologie
Collections:Open-Access-Publikationsfonds
Licence (German):Zweitveröffentlichung