start-ver=1.4
cd-journal=joma
no-vol=236
cd-vols=
no-issue=3
article-no=
start-page=864
end-page=877
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2022
dt-pub=20220817
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=A tonoplast‐localized magnesium transporter is crucial for stomatal opening in Arabidopsis under high Mg2+ conditions
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Plant stomata play an important role in CO2 uptake for photosynthesis and transpiration, but the mechanisms underlying stomatal opening and closing under changing environmental conditions are still not completely understood.
Through large-scale genetic screening, we isolated an Arabidopsis mutant (closed stomata2 (cst2)) that is defective in stomatal opening. We cloned the causal gene (MGR1/CST2) and functionally characterized this gene.
The mutant phenotype was caused by a mutation in a gene encoding an unknown protein with similarities to the human magnesium (Mg2+) efflux transporter ACDP/CNNM. MGR1/CST2 was localized to the tonoplast and showed transport activity for Mg2+. This protein was constitutively and highly expressed in guard cells. Knockout of this gene resulted in stomatal closing, decreased photosynthesis and growth retardation, especially under high Mg2+ conditions, while overexpression of this gene increased stomatal opening and tolerance to high Mg2+ concentrations. Furthermore, guard cell-specific expression of MGR1/CST2 in the mutant partially restored its stomatal opening.
Our results indicate that MGR1/CST2 expression in the leaf guard cells plays an important role in maintaining cytosolic Mg2+ concentrations through sequestering Mg2+ into vacuoles, which is required for stomatal opening, especially under high Mg2+ conditions.
en-copyright=
kn-copyright=
en-aut-name=InoueShin‐ichiro
en-aut-sei=Inoue
en-aut-mei=Shin‐ichiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=
en-aut-name=HayashiMaki
en-aut-sei=Hayashi
en-aut-mei=Maki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=
en-aut-name=HuangSheng
en-aut-sei=Huang
en-aut-mei=Sheng
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=
en-aut-name=YokoshoKengo
en-aut-sei=Yokosho
en-aut-mei=Kengo
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=
en-aut-name=GotohEiji
en-aut-sei=Gotoh
en-aut-mei=Eiji
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=
en-aut-name=IkematsuShuka
en-aut-sei=Ikematsu
en-aut-mei=Shuka
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=6
ORCID=
en-aut-name=OkumuraMasaki
en-aut-sei=Okumura
en-aut-mei=Masaki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=7
ORCID=
en-aut-name=SuzukiTakamasa
en-aut-sei=Suzuki
en-aut-mei=Takamasa
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=8
ORCID=
en-aut-name=KamuraTakumi
en-aut-sei=Kamura
en-aut-mei=Takumi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=9
ORCID=
en-aut-name=KinoshitaToshinori
en-aut-sei=Kinoshita
en-aut-mei=Toshinori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=10
ORCID=
en-aut-name=MaJian Feng
en-aut-sei=Ma
en-aut-mei=Jian Feng
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=11
ORCID=
affil-num=1
en-affil=Division of Biological Science, Graduate School of Science, Nagoya University
kn-affil=
affil-num=2
en-affil=Division of Biological Science, Graduate School of Science, Nagoya University
kn-affil=
affil-num=3
en-affil=Institute of Plant Science and Resources, Okayama University
kn-affil=
affil-num=4
en-affil=Institute of Plant Science and Resources, Okayama University
kn-affil=
affil-num=5
en-affil=Department of Forest Environmental Sciences, Faculty of Agriculture, Kyushu University
kn-affil=
affil-num=6
en-affil=Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University
kn-affil=
affil-num=7
en-affil=Division of Biological Science, Graduate School of Science, Nagoya University
kn-affil=
affil-num=8
en-affil=Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University
kn-affil=
affil-num=9
en-affil=Division of Biological Science, Graduate School of Science, Nagoya University
kn-affil=
affil-num=10
en-affil=Division of Biological Science, Graduate School of Science, Nagoya University
kn-affil=
affil-num=11
en-affil=Institute of Plant Science and Resources, Okayama University
kn-affil=
en-keyword=ACDP
kn-keyword=ACDP
en-keyword=CNNM
kn-keyword=CNNM
en-keyword=Arabidopsis thaliana
kn-keyword=Arabidopsis thaliana
en-keyword=magnesium transport
kn-keyword=magnesium transport
en-keyword=plant growth
kn-keyword=plant growth
en-keyword=stomatal opening
kn-keyword=stomatal opening
END
start-ver=1.4
cd-journal=joma
no-vol=6
cd-vols=
no-issue=
article-no=
start-page=
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2015
dt-pub=20150105
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=AtPHT4;4 is a chloroplast-localized ascorbate transporter in Arabidopsis
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Ascorbate is an antioxidant and coenzyme for various metabolic reactions in vivo. In plant chloroplasts, high ascorbate levels are required to overcome photoinhibition caused by strong light. However, ascorbate is synthesized in the mitochondria and the molecular mechanisms underlying ascorbate transport into chloroplasts are unknown. Here we show that AtPHT4;4, a member of the phosphate transporter 4 family of Arabidopsis thaliana, functions as an ascorbate transporter. In vitro analysis shows that proteoliposomes containing the purified AtPHT4;4 protein exhibit membrane potential- and Cl-dependent ascorbate uptake. The AtPHT4;4 protein is abundantly expressed in the chloroplast envelope membrane. Knockout of AtPHT4;4 results in decreased levels of the reduced form of ascorbate in the leaves and the heat dissipation process of excessive energy during photosynthesis is compromised. Taken together, these observations indicate that the AtPHT4;4 protein is an ascorbate transporter at the chloroplast envelope membrane, which may be required for tolerance to strong light stress.
en-copyright=
kn-copyright=
en-aut-name=MiyajiTakaaki
en-aut-sei=Miyaji
en-aut-mei=Takaaki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=
en-aut-name=KuromoriTakashi
en-aut-sei=Kuromori
en-aut-mei=Takashi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=
en-aut-name=TakeuchiYu
en-aut-sei=Takeuchi
en-aut-mei=Yu
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=
en-aut-name=YamajiNaoki
en-aut-sei=Yamaji
en-aut-mei=Naoki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=
en-aut-name=YokoshoKengo
en-aut-sei=Yokosho
en-aut-mei=Kengo
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=
en-aut-name=ShimazawaAtsushi
en-aut-sei=Shimazawa
en-aut-mei=Atsushi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=6
ORCID=
en-aut-name=SugimotoEriko
en-aut-sei=Sugimoto
en-aut-mei=Eriko
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=7
ORCID=
en-aut-name=OmoteHiroshi
en-aut-sei=Omote
en-aut-mei=Hiroshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=8
ORCID=
en-aut-name=MaJian Feng
en-aut-sei=Ma
en-aut-mei=Jian Feng
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=9
ORCID=
en-aut-name=ShinozakiKazuo
en-aut-sei=Shinozaki
en-aut-mei=Kazuo
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=10
ORCID=
en-aut-name=MoriyamaYoshinori
en-aut-sei=Moriyama
en-aut-mei=Yoshinori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=11
ORCID=
affil-num=1
en-affil=
kn-affil=Advanced Science Research Center, Okayama University
affil-num=2
en-affil=
kn-affil=Gene Discovery Research Group, RIKEN Center for Sustainable Resource Science
affil-num=3
en-affil=
kn-affil=Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
affil-num=4
en-affil=
kn-affil=Institute of Plant Science and Resources, Okayama University
affil-num=5
en-affil=
kn-affil=Institute of Plant Science and Resources, Okayama University
affil-num=6
en-affil=
kn-affil=Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
affil-num=7
en-affil=
kn-affil=Gene Discovery Research Group, RIKEN Center for Sustainable Resource Science
affil-num=8
en-affil=
kn-affil=Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
affil-num=9
en-affil=
kn-affil=Institute of Plant Science and Resources, Okayama University
affil-num=10
en-affil=
kn-affil=Gene Discovery Research Group, RIKEN Center for Sustainable Resource Science
affil-num=11
en-affil=
kn-affil=Advanced Science Research Center, Okayama University
END