Phospholipase Dα1 mediates the high-Mg2+ stress response partially through regulation of K+ homeostasis
Jazyk angličtina Země Spojené státy americké Médium print-electronic
Typ dokumentu časopisecké články, práce podpořená grantem
PubMed
32583878
DOI
10.1111/pce.13831
Knihovny.cz E-zdroje
- Klíčová slova
- Arabidopsis thaliana, CIPK9, HAK5, high magnesium, ion homeostasis, phospholipase D, potassium,
- MeSH
- Arabidopsis enzymologie metabolismus fyziologie MeSH
- draslík metabolismus MeSH
- fosfolipasa D metabolismus fyziologie MeSH
- fyziologický stres MeSH
- homeostáza MeSH
- hořčík metabolismus MeSH
- proteiny huseníčku metabolismus fyziologie MeSH
- transkriptom MeSH
- western blotting MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- draslík MeSH
- fosfolipasa D MeSH
- hořčík MeSH
- PLDA1 protein, Arabidopsis MeSH Prohlížeč
- proteiny huseníčku MeSH
Intracellular levels of Mg2+ are tightly regulated, as Mg2+ deficiency or excess affects normal plant growth and development. In Arabidopsis, we determined that phospholipase Dα1 (PLDα1) is involved in the stress response to high-magnesium conditions. The T-DNA insertion mutant pldα1 is hypersensitive to increased concentrations of magnesium, exhibiting reduced primary root length and fresh weight. PLDα1 activity increases rapidly after high-Mg2+ treatment, and this increase was found to be dose dependent. Two lines harbouring mutations in the HKD motif, which is essential for PLDα1 activity, displayed the same high-Mg2+ hypersensitivity of pldα1 plants. Moreover, we show that high concentrations of Mg2+ disrupt K+ homeostasis, and that transcription of K+ homeostasis-related genes CIPK9 and HAK5 is impaired in pldα1. Additionally, we found that the akt1, hak5 double mutant is hypersensitive to high-Mg2+ . We conclude that in Arabidopsis, the enzyme activity of PLDα1 is vital in the response to high-Mg2+ conditions, and that PLDα1 mediates this response partially through regulation of K+ homeostasis.
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