Regulation of ABA-Non-Activated SNF1-Related Protein Kinase 2 Signaling Pathways by Phosphatidic Acid

• Published in: International journal of molecular sciences Vol. 21; no. 14; p. 4984
• Main Authors: Klimecka, Maria, Bucholc, Maria, Maszkowska, Justyna, Krzywińska, Ewa, Goch, Grażyna, Lichocka, Małgorzata, Szczegielniak, Jadwiga, Dobrowolska, Grażyna
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 15-07-2020; MDPI
• Subjects: Abiotic stress; Abscisic acid; Abscisic Acid - metabolism; Arabidopsis - metabolism; Arabidopsis Proteins - analysis; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; Calcium; Dehydration; Dehydrin; dehydrins; Environmental effects; ERD14; Kinases; Localization; Membranes; Phosphatase; Phosphatidic acid; Phosphatidic Acids - metabolism; Phosphoprotein phosphatase; Phosphorylation; Plant cells; PP2CA; Protein Interaction Maps; Protein kinase; Protein phosphatase; Protein-Serine-Threonine Kinases - analysis; Protein-Serine-Threonine Kinases - metabolism; Proteins; Regulation; Regulators; Salinity; Salt; SCS; Signal Transduction; SnRK2-interacting calcium sensor; Arabidopsis thaliana; PA; SCS; dehydrins; SNF1-related protein kinases; SnRK2-interacting calcium sensor; ERD14; SnRK2; phosphatidic acid; PP2CA
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms21144984

Phosphatidic acid (PA) is involved in the regulation of plant growth and development, as well as responses to various environmental stimuli. Several PA targets in plant cells were identified, including two SNF1-related protein kinases 2 (SnRK2s), SnRK2.10 and SnRK2.4, which are not activated by abscisic acid (ABA). Here, we investigated the effects of PA on various elements of ABA-non-activated SnRK2 signaling. PA 16:0/18:1 was found to modulate the SnRK2 structure and the phosphorylation of some SnRK2 targets. Conversely, phosphorylation by the ABA-non-activated SnRK2s, of one of such targets, dehydrin Early Responsive to Dehydration 14 (ERD14), affects its interaction with PA and subcellular localization. Moreover, PA 16:0/18:1 modulates the activity and/or localization of negative regulators of the ABA-non-activated SnRK2s, not only of the ABA insensitive 1 (ABI1) phosphatase, which was identified earlier, but also of another protein phosphatase 2C, PP2CA. The activity of both phosphatases was inhibited by about 50% in the presence of 50 μM PA. PA 16:0/18:1 also impacts the phosphorylation and subcellular localization of SnRK2-interacting calcium sensor, known to inhibit SnRK2 activity in a calcium-dependent manner. Thus, PA was found to regulate ABA-non-activated SnRK2 signaling at several levels: the activity, phosphorylation status and/or localization of SnRK2 cellular partners.