Abstract
Abscisic acid (ABA) regulation of stomatal aperture is known to involve both Ca2+-dependent and Ca2+-independent signal transduction pathways. Electrophysiological studies suggest that protein phosphorylation is involved in ABA action in guard cells. Using biochemical approaches, we identified an ABA-activated and Ca2+- independent protein kinase (AAPK) from guard cell protoplasts of fava bean. Autophosphorylation of AAPK was rapidly (~1 min) activated by ABA in a Ca2+- independent manner. ABA-activated autophosphorylation of AAPK occurred on serine but not on tyrosine residues and appeared to be guard cell specific. AAPK phosphorylated histone type III-S on serine and threonine residues, and its activity toward histone type III-S was markedly stimulated in ABA-treated guard cell protoplasts. Our results suggest that AAPK may play an important role in the Ca2+-independent ABA signaling pathways of guard cells.
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Claims 6
Claim · model-written summary
An ABA-activated, Ca2+-independent kinase AAPK was identified from fava bean guard cells.
- Taxon
- fava bean
Vicia fabae0 - Organ / stage
- guard cell protoplastse0
- Gene
- AAPKe0
- Outcome
- ABA-activated and Ca2+- independent protein kinasee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we identified an ABA-activated and Ca2+- independent protein kinase (AAPK) from guard cell protoplasts of fava bean”
Claim · model-written summary
ABA rapidly activated AAPK autophosphorylation in a Ca2+-independent manner.
- Taxon
- fava beanVicia fabae1
- Treatment
- ABAe0
- Gene
- AAPKe0
- Outcome
- Autophosphorylation of AAPKe0
- Direction
- activatede0
- Value
- ~1 mine0
- Qualifier
- Ca2+- independent mannere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Autophosphorylation of AAPK was rapidly (~1 min) activated by ABA in a Ca2+- independent manner.”
e1“guard cell protoplasts of fava bean”
Claim · model-written summary
ABA-activated AAPK autophosphorylation occurred on serine but not tyrosine and appeared guard-cell specific.
- Taxon
- fava beanVicia fabae1
- Organ / stage
- guard celle0
- Gene
- AAPKe0
- Outcome
- autophosphorylation of AAPK occurred on serine but not on tyrosine residuese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ABA-activated autophosphorylation of AAPK occurred on serine but not on tyrosine residues and appeared to be guard cell specific.”
e1“guard cell protoplasts of fava bean”
Claim · model-written summary
AAPK phosphorylated histone type III-S on serine and threonine.
- Taxon
- fava beanVicia fabae1
- Gene
- AAPKe0
- Outcome
- phosphorylated histone type III-S on serine and threonine residuese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“AAPK phosphorylated histone type III-S on serine and threonine residues”
e1“guard cell protoplasts of fava bean”
Claim · model-written summary
ABA treatment markedly stimulated AAPK activity toward histone type III-S in guard-cell protoplasts.
- Taxon
- fava beanVicia fabae1
- Organ / stage
- guard cell protoplastse0
- Treatment
- ABA-treatede0
- Gene
- histone type III-Se0
- Outcome
- activity toward histone type III-Se0
- Direction
- stimulatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“its activity toward histone type III-S was markedly stimulated in ABA-treated guard cell protoplasts”
e1“guard cell protoplasts of fava bean”
Claim · model-written summary
Authors suggest AAPK may contribute to Ca2+-independent ABA signaling in guard cells.
- Taxon
- fava beanVicia fabae1
- Organ / stage
- guard cellse0
- Gene
- AAPKe0
- Outcome
- Ca2+-independent ABA signaling pathwayse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“AAPK may play an important role in the Ca2+-independent ABA signaling pathways of guard cells”
e1“guard cell protoplasts of fava bean”
The same questions in other papers
(+)-abscisic acid · molecular: metabolites · Vicia faba (faba bean)Results differ
4 papers in the same direction as this paper · 3 in the opposite direction
- positive
- no effect
- negative
4 papers more in this group
See all 8 papers →(+)-abscisic acid · quality: protein · Vicia faba (faba bean)Results agree
1 paper in the same direction as this paper
- positive
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.