Involvement of the Membrane Nanodomain Protein, <i>At</i>Flot1, in Vesicular Transport of Plasma Membrane H<sup>+</sup>-ATPase in <i>Arabidopsis thaliana</i> under Salt Stress
The aim of this study was to elucidate whether the membrane nanodomain protein <i>At</i>Flot1 is involved in vesicular transport pathways and regulation of the P-type H<sup>+</sup>-ATPase content in plasma membrane of <i>A. thaliana</i> under salt stress. Transmis...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-01-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/24/2/1251 |
| Summary: | The aim of this study was to elucidate whether the membrane nanodomain protein <i>At</i>Flot1 is involved in vesicular transport pathways and regulation of the P-type H<sup>+</sup>-ATPase content in plasma membrane of <i>A. thaliana</i> under salt stress. Transmission electron microscopy revealed changes in the endosomal system of <i>A. thaliana</i> root cells due to knockout mutation SALK_205125C (<i>Atflot1ko</i>). Immunoblotting of the plasma membrane-enriched fractions isolated from plant organs with an antibody to the H<sup>+</sup>-ATPase demonstrated changes in the H<sup>+</sup>-ATPase content in plasma membrane in response to the <i>Atflot1ko</i> mutation and salt shock. Expression levels of the main H<sup>+</sup>-ATPase isoforms, <i>PMA1</i> and <i>PMA2</i>, as well as endocytosis activity of root cells determined by endocytic probe FM4-64 uptake assay, were unchanged in the <i>Atflot1ko</i> mutant. We have shown that <i>At</i>Flot1 participates in regulation of the H<sup>+</sup>-ATPase content in the plasma membrane. We hypothesized that <i>At</i>Flot1 is involved in both exocytosis and endocytosis, and, thus, contributes to the maintenance of cell ion homeostasis under salt stress. The lack of a pronounced <i>Atflot1ko</i> phenotype under salt stress conditions may be due to the assumed ability of <i>Atflot1ko</i> to switch vesicular transport to alternative pathways. Functional redundancy of <i>At</i>Flot proteins may play a role in the functioning of these alternative pathways. |
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| ISSN: | 1661-6596 1422-0067 |