The CIPK23 protein kinase represses SLAC1-type anion channels in Arabidopsis guard cells and stimulates stomatal opening.
New Phytol
; 238(1): 270-282, 2023 04.
Article
em En
| MEDLINE
| ID: mdl-36597715
ABSTRACT
Guard cells control the opening of stomatal pores in the leaf surface, with the use of a network of protein kinases and phosphatases. Loss of function of the CBL-interacting protein kinase 23 (CIPK23) was previously shown to decrease the stomatal conductance, but the molecular mechanisms underlying this response still need to be clarified. CIPK23 was specifically expressed in Arabidopsis guard cells, using an estrogen-inducible system. Stomatal movements were linked to changes in ion channel activity, determined with double-barreled intracellular electrodes in guard cells and with the two-electrode voltage clamp technique in Xenopus oocytes. Expression of the phosphomimetic variant CIPK23T190D enhanced stomatal opening, while the natural CIPK23 and a kinase-inactive CIPK23K60N variant did not affect stomatal movements. Overexpression of CIPK23T190D repressed the activity of S-type anion channels, while their steady-state activity was unchanged by CIPK23 and CIPK23K60N . We suggest that CIPK23 enhances the stomatal conductance at favorable growth conditions, via the regulation of several ion transport proteins in guard cells. The inhibition of SLAC1-type anion channels is an important facet of this response.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
/
Proteínas de Arabidopsis
Idioma:
En
Revista:
New Phytol
Assunto da revista:
BOTANICA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Alemanha