Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Front Plant Sci
2020 Feb 26;11:144. doi: 10.3389/fpls.2020.00144.
Show Gene links
Show Anatomy links
Functional Characterization of the Arabidopsis Abscisic Acid Transporters NPF4.5 and NPF4.6 in Xenopus Oocytes.
Léran S
,
Noguero M
,
Corratgé-Faillie C
,
Boursiac Y
,
Brachet C
,
Lacombe B
.
???displayArticle.abstract???
Few proteins have been characterized as abscisic acid transporters. Several of them are NRT1/PRT Family (NPF) transporters which have been characterized in yeast using reporter systems. Because several members of the NPF4 subfamily members were identified in yeast as ABA transporters, here, we screened for ABA transport activity the seven members of the NPF4 subfamily in Xenopus oocytes using cRNA injection and 3H-ABA accumulation. The ABA transport capacities of NPF4.2, NPF4.5, NPF4.6, and NPF4.7 were confirmed. The transport properties of NPF4.5 and NPF4.6 were studied in more detail. Both ABA transporter activities are pH-dependent and slightly pH-dependent apparent Km around 500 μM. There is no competitive inhibition of the ABA-analogs pyrabactin and quinabactin on ABA accumulation demonstrating a different selectivity compared to the ABA receptors. Functional expression of these ABA transporters in Xenopus oocyte is an opportunity to start structure-function studies and also to identify partner proteins of these hormone transporters.
Figure 1. Screen for ABA transport activity of Arabidopsis NPF4 subfamily members in Xenopus oocytes. Control (noninjected) and NPF4-injected oocytes were bathed in 1 μM 3H-ABA (pH = 6.0), and 3H accumulation in oocytes was quantified after 20 min. Values are mean +/â SEM (n = 5â12 oocytes, biological replicates). ***P < 0.001, **0.001 < P < 0.005, two-sided t-test after comparison with control oocytes.
Figure 2. pH-dependent 3H accumulation in NPF4.5 and NPF4.6 in Xenopus oocytes. Control (noninjected, black circles), NPF4.5 (green circles) and NPF4.6 (red circles) injected oocytes were bathed in 1 μM 3H-ABA (pH = 5.0 to 7.5), and 3H accumulation in oocytes was quantified after 20 min. Values are mean +/â SEM (n = 6â20 oocytes, biological replicates). ***P < 0.001, **0.001 < P < 0.005, two-sided t-test after comparison with control oocytes.
Figure 3. Effect of external ABA concentration on 3H accumulation in NPF4.5 and NPF4.6-expressing oocytes. 3H-accumulation in NPF4.5 (A) and NPF4.6 (B) expressing oocytes depending on the wide external ABA concentrations range (0â5 μM 3H-ABA). The solid lines are least-squares Michaelian fits. Data are mean +/â SE (n = 6â10 oocytes, biological replicates).
Figure 4. Effect of pyrabactin and quinabactin on 3H accumulation in NPF4.5 and NPF4.6 in Xenopus oocytes. Control (noninjected), NPF4.5 and NPF4.6 injected oocytes were bathed in 1 μM 3H-ABA (pH = 6.0), and 3H accumulation in oocytes was quantified after 20 min in the presence or in the absence of 0.5 or 5 μM of pyrabactin or quinabactin. Values are mean +/â SEM (n = 9â11 oocytes, biological replicates). The pyrabactin and quinabactin treatment has no significant effect on 3H accumulation (two-sided t-test).
Boursiac,
ABA transport and transporters.
2013, Pubmed
Boursiac,
ABA transport and transporters.
2013,
Pubmed
Cao,
Combining chemical and genetic approaches to increase drought resistance in plants.
2017,
Pubmed
Chiba,
Identification of Arabidopsis thaliana NRT1/PTR FAMILY (NPF) proteins capable of transporting plant hormones.
2015,
Pubmed
Corratgé-Faillie,
Substrate (un)specificity of Arabidopsis NRT1/PTR FAMILY (NPF) proteins.
2017,
Pubmed
Cutler,
Abscisic acid: emergence of a core signaling network.
2010,
Pubmed
Huang,
Cloning and functional characterization of an Arabidopsis nitrate transporter gene that encodes a constitutive component of low-affinity uptake.
1999,
Pubmed
,
Xenbase
Jørgensen,
Origin and evolution of transporter substrate specificity within the NPF family.
2017,
Pubmed
,
Xenbase
Jørgensen,
A Functional EXXEK Motif is Essential for Proton Coupling and Active Glucosinolate Transport by NPF2.11.
2015,
Pubmed
Kang,
PDR-type ABC transporter mediates cellular uptake of the phytohormone abscisic acid.
2010,
Pubmed
Kang,
Abscisic acid transporters cooperate to control seed germination.
2015,
Pubmed
Kanno,
Nitrate does not compete with abscisic acid as a substrate of AtNPF4.6/NRT1.2/AIT1 in Arabidopsis.
2013,
Pubmed
Kanno,
Identification of an abscisic acid transporter by functional screening using the receptor complex as a sensor.
2012,
Pubmed
Kuromori,
ABA Transport and Plant Water Stress Responses.
2018,
Pubmed
Kuromori,
ABC transporter AtABCG25 is involved in abscisic acid transport and responses.
2010,
Pubmed
Kuromori,
Overexpression of AtABCG25 enhances the abscisic acid signal in guard cells and improves plant water use efficiency.
2016,
Pubmed
Kuromori,
ABA transport factors found in Arabidopsis ABC transporters.
2010,
Pubmed
Lacombe,
Evidence for a multi-ion pore behavior in the plant potassium channel KAT1.
1998,
Pubmed
,
Xenbase
Larsen,
Advances in methods for identification and characterization of plant transporter function.
2017,
Pubmed
,
Xenbase
Léran,
AtNPF5.5, a nitrate transporter affecting nitrogen accumulation in Arabidopsis embryo.
2015,
Pubmed
,
Xenbase
Longo,
Genome Mining of Plant NPFs Reveals Varying Conservation of Signature Motifs Associated With the Mechanism of Transport.
2018,
Pubmed
Ma,
Regulators of PP2C phosphatase activity function as abscisic acid sensors.
2009,
Pubmed
Nambara,
Abscisic acid biosynthesis and catabolism.
2005,
Pubmed
Okamoto,
Activation of dimeric ABA receptors elicits guard cell closure, ABA-regulated gene expression, and drought tolerance.
2013,
Pubmed
Park,
Abscisic acid inhibits type 2C protein phosphatases via the PYR/PYL family of START proteins.
2009,
Pubmed
Pawela,
MtABCG20 is an ABA exporter influencing root morphology and seed germination of Medicago truncatula.
2019,
Pubmed
Pellizzaro,
The nitrate transporter MtNPF6.8 (MtNRT1.3) transports abscisic acid and mediates nitrate regulation of primary root growth in Medicago truncatula.
2014,
Pubmed
,
Xenbase
Tal,
The Arabidopsis NPF3 protein is a GA transporter.
2016,
Pubmed
Wulff,
An Optimized Screen Reduces the Number of GA Transporters and Provides Insights Into Nitrate Transporter 1/Peptide Transporter Family Substrate Determinants.
2019,
Pubmed
,
Xenbase
Yao,
The AWPM-19 Family Protein OsPM1 Mediates Abscisic Acid Influx and Drought Response in Rice.
2018,
Pubmed
Zhang,
A DTX/MATE-type transporter facilitates abscisic acid efflux and modulates ABA sensitivity and drought tolerance in Arabidopsis.
2014,
Pubmed
,
Xenbase
