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Shang J, Mu G, Qi Y, Zhang X, Shen W, Xie Y, Ge M, He Y, Qiao F, Qiu QS. NHX5/NHX6/SPY22 complex regulates BRI1 and brassinosteroid signaling in Arabidopsis. JOURNAL OF PLANT PHYSIOLOGY 2024; 302:154318. [PMID: 39059150 DOI: 10.1016/j.jplph.2024.154318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 07/21/2024] [Accepted: 07/22/2024] [Indexed: 07/28/2024]
Abstract
NHX5 and NHX6, Arabidopsis endosomal antiporters, play a vital role in facilitating ion and pH homeostasis in endosomal compartments. Studies have found that NHX5 and NHX6 are essential for protein trafficking, auxin homeostasis, and plant growth and development. Here, we report the role of NHX5 and NHX6 in brassinosteroid (BR) signaling. We found that hypocotyl growth was enhanced in nhx5 nhx6 under epibrassinolide (eBR) treatment. nhx5 nhx6 bri1 was insensitive to eBR treatment, indicating that NHX5 and NHX6 are downstream of the BRI1 receptor in BR signaling. Moreover, confocal observation with both hypocotyls and root tips showed that BRI1-YFP localization in the plasma membrane (PM) was reduced in nhx5 nhx6. Interestingly, brefeldin A (BFA) treatment showed that formation of the BFA bodies containing BRI1 and their disassembling were disrupted in nhx5 nhx6. Further genetic analysis showed that NHX5/NHX6 and SYP22 may act coordinately in BR signaling. NHX5 and NHX6 may regulate SYP22 function by modulating cellular K+ and pH homeostasis. Importantly, NHX5 and NHX6 colocalize and interact with SYP22, but do not interact with BRI1. In summary, our findings indicate that NHX5/NHX6/SYP22 complex is essential for the regulation of BRI1 recycling and PM localization. The H+-leak facilitated by NHX5 and NHX6 offers a means of controlling BR signaling in plants.
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Affiliation(s)
- Jun Shang
- Academy of Plateau Science and Sustainability, School of Life Sciences, Qinghai Normal University, Xining, Qinghai, 810000, China
| | - Guoxiu Mu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Yuting Qi
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Xiao Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China; College of Life Science and Technology, Tarim University, Alar, 843300, China
| | - Wei Shen
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Yujie Xie
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Mingrui Ge
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Yu He
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Feng Qiao
- Academy of Plateau Science and Sustainability, School of Life Sciences, Qinghai Normal University, Xining, Qinghai, 810000, China
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China.
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Zhang X, Wang L, Pan T, Wu X, Shen J, Jiang L, Tajima H, Blumwald E, Qiu QS. Plastid KEA-type cation/H + antiporters are required for vacuolar protein trafficking in Arabidopsis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023; 65:2157-2174. [PMID: 37252889 DOI: 10.1111/jipb.13537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 05/28/2023] [Indexed: 06/01/2023]
Abstract
Arabidopsis plastid antiporters KEA1 and KEA2 are critical for plastid development, photosynthetic efficiency, and plant development. Here, we show that KEA1 and KEA2 are involved in vacuolar protein trafficking. Genetic analyses found that the kea1 kea2 mutants had short siliques, small seeds, and short seedlings. Molecular and biochemical assays showed that seed storage proteins were missorted out of the cell and the precursor proteins were accumulated in kea1 kea2. Protein storage vacuoles (PSVs) were smaller in kea1 kea2. Further analyses showed that endosomal trafficking in kea1 kea2 was compromised. Vacuolar sorting receptor 1 (VSR1) subcellular localizations, VSR-cargo interactions, and p24 distribution on the endoplasmic reticulum (ER) and Golgi apparatus were affected in kea1 kea2. Moreover, plastid stromule growth was reduced and plastid association with the endomembrane compartments was disrupted in kea1 kea2. Stromule growth was regulated by the cellular pH and K+ homeostasis maintained by KEA1 and KEA2. The organellar pH along the trafficking pathway was altered in kea1 kea2. Overall, KEA1 and KEA2 regulate vacuolar trafficking by controlling the function of plastid stromules via adjusting pH and K+ homeostasis.
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Affiliation(s)
- Xiao Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 73000, China
- Academy of Plateau Science and Sustainability, School of Life Sciences, Qinghai Normal University, Xining, 810000, China
- College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, 524088, China
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Lanzhou, 730000, China
| | - Lu Wang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 73000, China
- Academy of Plateau Science and Sustainability, School of Life Sciences, Qinghai Normal University, Xining, 810000, China
- College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, 524088, China
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Lanzhou, 730000, China
| | - Ting Pan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 73000, China
| | - Xuexia Wu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 73000, China
| | - Jinbo Shen
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
| | - Hiromi Tajima
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA
| | - Eduardo Blumwald
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 73000, China
- Academy of Plateau Science and Sustainability, School of Life Sciences, Qinghai Normal University, Xining, 810000, China
- College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, 524088, China
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Lanzhou, 730000, China
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Jin T, An J, Xu H, Chen J, Pan L, Zhao R, Wang N, Gai J, Li Y. A soybean sodium/hydrogen exchanger GmNHX6 confers plant alkaline salt tolerance by regulating Na +/K + homeostasis. FRONTIERS IN PLANT SCIENCE 2022; 13:938635. [PMID: 36204047 PMCID: PMC9531905 DOI: 10.3389/fpls.2022.938635] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 08/30/2022] [Indexed: 06/15/2023]
Abstract
Alkaline soil has a high pH due to carbonate salts and usually causes more detrimental effects on crop growth than saline soil. Sodium hydrogen exchangers (NHXs) are pivotal regulators of cellular Na+/K+ and pH homeostasis, which is essential for salt tolerance; however, their role in alkaline salt tolerance is largely unknown. Therefore, in this study, we investigated the function of a soybean NHX gene, GmNHX6, in plant response to alkaline salt stress. GmNHX6 encodes a Golgi-localized sodium/hydrogen exchanger, and its transcript abundance is more upregulated in alkaline salt tolerant soybean variety in response to NaHCO3 stress. Ectopic expression of GmNHX6 in Arabidopsis enhanced alkaline salt tolerance by maintaining high K+ content and low Na+/K+ ratio. Overexpression of GmNHX6 also improved soybean tolerance to alkaline salt stress. A single nucleotide polymorphism in the promoter region of NHX6 is associated with the alkaline salt tolerance in soybean germplasm. A superior promoter of GmNHX6 was isolated from an alkaline salt tolerant soybean variety, which showed stronger activity than the promoter from an alkaline salt sensitive soybean variety in response to alkali stress, by luciferase transient expression assays. Our results suggested soybean NHX6 gene plays an important role in plant tolerance to alkaline salt stress.
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Saddhe AA, Mishra AK, Kumar K. Molecular insights into the role of plant transporters in salt stress response. PHYSIOLOGIA PLANTARUM 2021; 173:1481-1494. [PMID: 33963568 DOI: 10.1111/ppl.13453] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 03/29/2021] [Accepted: 05/06/2021] [Indexed: 05/23/2023]
Abstract
Salt stress disturbs the cellular osmotic and ionic balance, which then creates a negative impact on plant growth and development. The Na+ and Cl- ions can enter into plant cells through various membrane transporters, including specific and non-specific Na+ , K+ , and Ca2+ transporters. Therefore, it is important to understand Na+ and K+ transport mechanisms in plants along with the isolation of genes, their characterization, the structural features, and their post-translation regulation under salt stress. This review summarizes the molecular insights of plant ion transporters, including non-selective cation transporters, cyclic nucleotide-gated cation transporters, glutamate-like receptors, membrane intrinsic proteins, cation proton antiporters, and sodium proton antiporter families. Further, we discussed the K+ transporter families such as high-affinity K+ transporters, HAK/KUP/KT transporters, shaker type K+ transporters, and K+ efflux antiporters. Besides the ion transport process, we have shed light on available literature on epigenetic regulation of transport processes under salt stress. Recent advancements of salt stress sensing mechanisms and various salt sensors within signaling transduction pathways are discussed. Further, we have compiled salt-stress signaling pathways, and their crosstalk with phytohormones.
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Affiliation(s)
- Ankush Ashok Saddhe
- Department of Biological Sciences, Birla Institute of Technology and Science Pilani, K. K. Birla Goa Campus, Goa, 403726, India
| | - Ajay Kumar Mishra
- Biology Centre, Czech Academy of Sciences, Department of Molecular Genetics, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Kundan Kumar
- Department of Biological Sciences, Birla Institute of Technology and Science Pilani, K. K. Birla Goa Campus, Goa, 403726, India
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Gao S, Zhang X, Wang L, Wang X, Zhang H, Xie H, Ma Y, Qiu QS. Arabidopsis antiporter CHX23 and auxin transporter PIN8 coordinately regulate pollen growth. JOURNAL OF PLANT PHYSIOLOGY 2021; 266:153539. [PMID: 34628190 DOI: 10.1016/j.jplph.2021.153539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/27/2021] [Accepted: 09/27/2021] [Indexed: 05/08/2023]
Abstract
Both the antiporter CHX23 (Cation/Proton Exchangers 23) and auxin transporter PIN8 (PIN-FORMED 8) are localized in the ER and regulate pollen growth in Arabidopsis. But how these two proteins regulate pollen growth remains to be studied. Here, we report that CHX23 and PIN8 act coordinately in regulating pollen growth. The chx23 mutant was reduced in pollen growth and normally shaped pollen grains, and complementation with CHX23 restored both pollen growth and normal pollen morphology. NAA treatments showed that CHX23 was crucial for pollen auxin homeostasis. The pin8 chx23 double mutant was decreased in pollen growth and normal pollen grains, indicating the joint effort of CHX23 and PIN8 in pollen growth. In vivo germination assay showed that CHX23 and PIN8 were involved in the early stage of pollen growth. CHX23 and PIN8 also function collaboratively in maintaining pollen auxin homeostasis. PIN8 depends on CHX23 in regulating pollen morphology and response to NAA treatments. CHX23 co-localized with PIN8, but there was no physical interaction. KCl and NaCl treatments showed that pollen growth of chx23 was reduced less than Col-0; pin8 chx23 was reduced less than chx23 and pin8. Together, CHX23 may regulate PIN8 function and hence pollen growth through controlling K+ and Na+ homeostasis mediated by its transport activity.
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Affiliation(s)
- Shenglan Gao
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xiao Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Lu Wang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xiufang Wang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Hua Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Huichun Xie
- Qinghai Provincial Key Laboratory of Medicinal Plant and Animal Resources of Qinghai-Tibet Plateau, School of Life Sciences, Qinghai Normal University, Xining, 810008, China
| | - Yonggui Ma
- Qinghai Provincial Key Laboratory of Medicinal Plant and Animal Resources of Qinghai-Tibet Plateau, School of Life Sciences, Qinghai Normal University, Xining, 810008, China
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.
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Lv S, Wang L, Zhang X, Li X, Fan L, Xu Y, Zhao Y, Xie H, Sawchuk MG, Scarpella E, Qiu QS. Arabidopsis NHX5 and NHX6 regulate PIN6-mediated auxin homeostasis and growth. JOURNAL OF PLANT PHYSIOLOGY 2020; 255:153305. [PMID: 33129075 DOI: 10.1016/j.jplph.2020.153305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 10/06/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
NHX5 and NHX6, endosomal Na+,K+/H+ antiporters in Arabidopsis thaliana, play a vital role in growth and development. Our previous study has shown that NHX5 and NHX6 function as H+ leak to regulate auxin-mediated growth in Arabidopsis. In this report, we investigated the function of NHX5 and NHX6 in controlling PIN6-mediated auxin homeostasis and growth in Arabidopsis. Phenotypic analyses found that NHX5 and NHX6 were critical for the function of PIN6, an auxin transporter. We further showed that PIN6 depended on NHX5 and NHX6 in regulating auxin homeostasis. NHX5 and NHX6 were colocalized with PIN6, but they did not interact physically. The conserved acidic residues that are vital for the activity of NHX5 and NHX6 were critical for PIN6 function. Together, NHX5 and NHX6 may regulate PIN6 function by their transport activity.
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Affiliation(s)
- Shasha Lv
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China
| | - Lu Wang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China
| | - Xiao Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China
| | - Xiaojiao Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China
| | - Ligang Fan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China
| | - Yanli Xu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China
| | - Yingjia Zhao
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China
| | - Huichun Xie
- Qinghai Provincial Key Laboratory of Medicinal Plant and Animal Resources of Qinghai-Tibet Plateau, School of Life Sciences, Qinghai Normal University, Xining, Qinghai, 810008, China
| | - Megan G Sawchuk
- Department of Biological Sciences, University of Alberta, CW-405 Biological Sciences Building, Edmonton AB T6G 2E9, Canada
| | - Enrico Scarpella
- Department of Biological Sciences, University of Alberta, CW-405 Biological Sciences Building, Edmonton AB T6G 2E9, Canada
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China.
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Zhang X, Li Z, Li X, Xu Y, Xie H, Qiu QS. CBL3 and CIPK18 are required for the function of NHX5 and NHX6 in mediating Li + homeostasis in Arabidopsis. JOURNAL OF PLANT PHYSIOLOGY 2020; 255:153295. [PMID: 33129077 DOI: 10.1016/j.jplph.2020.153295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 06/11/2023]
Abstract
Arabidopsis NHX5 and NHX6 are endosomal Na+,K+/H+ antiporters that function in mediating Na+, K+ and pH homeostasis. Here, we report that NHX5 and NHX6 mediate Li+ homeostasis in Arabidopsis. We found that the nhx5 nhx6 double mutant was defective in growth and had a high pale rate under Li+ stress; complementation with either NHX5 or NHX6 restored the growth of the double mutant under LiCl treatments. We further found that CBL3 and CIPK18 collaborate with NHX5 and NHX6 in controlling seedling growth. CBL3 and CIPK18 are involved in the NHX5- and NHX6-mediated response to Li+ stress but not to salt or low K+ stress. In addition, NHX5 and NHX6 coordinate NHX8, a plasma membrane antiporter, in mediating Li+ homeostasis. NHX8 may function differently from NHX5 and NHX6 in mediating Li+ homeostasis. NHX8 was not controlled by CBL3 and CIPK18. Overall, CBL3 and CIPK18 are required for the function of NHX5 and NHX6 in mediating Li+ homeostasis in Arabidopsis.
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Affiliation(s)
- Xiao Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Zhanchao Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xiaojiao Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Yanli Xu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Huichun Xie
- Qinghai Provincial Key Laboratory of Medicinal Plant and Animal Resources of Qinghai-Tibet Plateau, School of Life Sciences, Qinghai Normal University, Xining, Qinghai, 810008, China
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.
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Al-Harrasi I, Jana GA, Patankar HV, Al-Yahyai R, Rajappa S, Kumar PP, Yaish MW. A novel tonoplast Na +/H + antiporter gene from date palm (PdNHX6) confers enhanced salt tolerance response in Arabidopsis. PLANT CELL REPORTS 2020; 39:1079-1093. [PMID: 32382811 DOI: 10.1007/s00299-020-02549-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 04/25/2020] [Indexed: 05/17/2023]
Abstract
A sodium hydrogen exchanger (NHX) gene from the date palm enhances tolerance to salinity in Arabidopsis plants. Plant sodium hydrogen exchangers/antiporters (NHXs) are pivotal regulators of intracellular Na+/K+ and pH homeostasis, which is essential for salt stress adaptation. In this study, a novel orthologue of Na+/H+ antiporter was isolated from date palm (PdNHX6) and functionally characterized in mutant yeast cells and Arabidopsis plants to assess the behavior of the transgenic organisms in response to salinity. Genetically transformed yeast cells with PdNHX6 were sensitive to salt stress when compared to the empty vector (EV) yeast cells. Besides, the acidity value of the vacuoles of the transformant yeast cells has significantly (p ≤ 0.05) increased, as indicated by the calibrated fluorescence intensity measurements and the fluorescence imagining analyses. This observation supports the notion that PdNHX6 might regulate proton pumping into the vacuole, a crucial salt tolerance mechanism in the plants. Consistently, the transient overexpression and subcellular localization revealed the accumulation of PdNHX6 in the tonoplast surrounding the central vacuole of Nicotiana benthamiana leaf epidermal cells. Stable overexpression of PdNHX6 in Arabidopsis plants enhanced tolerance to salt stress and retained significantly higher chlorophyll, water contents, and increased seed germination under salinity when compared to the wild-type plants. Despite the significant increase of Na+, transgenic Arabidopsis lines maintained a balanced Na+/K+ ratio under salt stress conditions. Together, the results obtained from this study imply that PdNHX6 is involved in the salt tolerance mechanism in plants by controlling K+ and pH homeostasis of the vacuoles.
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Affiliation(s)
- Ibtisam Al-Harrasi
- Department of Biology, College of Sciences, Sultan Qaboos University, P.O. Box 36, 123, Muscat, Oman
| | - Gerry Aplang Jana
- Department of Biology, College of Sciences, Sultan Qaboos University, P.O. Box 36, 123, Muscat, Oman
| | - Himanshu V Patankar
- Department of Biology, College of Sciences, Sultan Qaboos University, P.O. Box 36, 123, Muscat, Oman
| | - Rashid Al-Yahyai
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box 34, 123, Muscat, Oman
| | - Sivamathini Rajappa
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Singapore
| | - Prakash P Kumar
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Singapore
| | - Mahmoud W Yaish
- Department of Biology, College of Sciences, Sultan Qaboos University, P.O. Box 36, 123, Muscat, Oman.
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Krishnamurthy P, Vishal B, Khoo K, Rajappa S, Loh CS, Kumar PP. Expression of AoNHX1 increases salt tolerance of rice and Arabidopsis, and bHLH transcription factors regulate AtNHX1 and AtNHX6 in Arabidopsis. PLANT CELL REPORTS 2019; 38:1299-1315. [PMID: 31350571 DOI: 10.1007/s00299-019-02450-w] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 07/22/2019] [Indexed: 05/17/2023]
Abstract
Expression of AoNHX1 from the mangrove Avicennia increases salt tolerance of rice and Arabidopsis, and specific bHLH transcription factors regulate AtNHX1 and AtNHX6 in Arabidopsis to mediate the salinity response. Improving crop plants to better tolerate soil salinity is a challenging task. Mangrove trees such as Avicennia officinalis have special adaptations to thrive in high salt conditions, which include subcellular compartmentalization of ions facilitated by specialized ion transporters. We identified and characterized two genes encoding Na+/H+ exchangers AoNHX1 and AoNHX6 from Avicennia. AoNHX1 was present in the tonoplast, while, AoNHX6 was localized to the ER and Golgi. Both NHXs were induced by NaCl treatment, with AoNHX1 showing high expression levels in the leaves and AoNHX6 in the seedling roots. Yeast deletion mutants (ena1-5Δ nha1Δ nhx1Δ and ena1-5Δ nha1Δ vnx1Δ) complemented with AoNHX1 and AoNHX6 showed increased tolerance to both NaCl and KCl. Expression of AoNHX1 and AoNHX6 in the corresponding Arabidopsis mutants conferred enhanced NaCl tolerance. The underlying molecular regulatory mechanism was investigated using AtNHX1 and AtNHX6 in Arabidopsis. We identified two basic helix-loop-helix (bHLH) transcription factors AtMYC2 and AtbHLH122 as the ABA-mediated upstream regulators of AtNHX1 and AtNHX6 by chromatin immunoprecipitation. Furthermore, expression of AtNHX1 and AtNHX6 transcripts was reduced in the atmyc2 and atbhlh122 mutants. Lastly, transgenic rice seedlings harboring pUBI::AoNHX1 showed enhanced salt tolerance, suggesting that this gene can be exploited for developing salt-tolerant crops.
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Affiliation(s)
- Pannaga Krishnamurthy
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
- NUS Environmental Research Institute (NERI), National University of Singapore, #02-01, T-Lab Building, 5A Engineering Drive 1, Singapore, 117411, Singapore
| | - Bhushan Vishal
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Kaijie Khoo
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Sivamathini Rajappa
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Chiang-Shiong Loh
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
- NUS Environmental Research Institute (NERI), National University of Singapore, #02-01, T-Lab Building, 5A Engineering Drive 1, Singapore, 117411, Singapore
| | - Prakash P Kumar
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
- NUS Environmental Research Institute (NERI), National University of Singapore, #02-01, T-Lab Building, 5A Engineering Drive 1, Singapore, 117411, Singapore.
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Zhu J, Ren Y, Wang Y, Liu F, Teng X, Zhang Y, Duan E, Wu M, Zhong M, Hao Y, Zhu X, Lei J, Wang Y, Yu Y, Pan T, Bao Y, Wang Y, Wan J. OsNHX5-mediated pH homeostasis is required for post-Golgi trafficking of seed storage proteins in rice endosperm cells. BMC PLANT BIOLOGY 2019; 19:295. [PMID: 31277576 PMCID: PMC6612104 DOI: 10.1186/s12870-019-1911-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 06/27/2019] [Indexed: 05/16/2023]
Abstract
BACKGROUND As the major storage protein in rice seeds, glutelins are synthesized at the endoplasmic reticulum (ER) as proglutelins and transported to protein storage vacuoles (PSVs) called PBIIs (Protein body IIs), where they are cleaved into mature forms by the vacuolar processing enzymes. However, the molecular mechanisms underlying glutelin trafficking are largely unknown. RESULTS In this study, we report a rice mutant, named glutelin precursor accumulation6 (gpa6), which abnormally accumulates massive proglutelins. Cytological analyses revealed that in gpa6 endosperm cells, proglutelins were mis-sorted, leading to the presence of dense vesicles (DVs) and the formation paramural bodies (PMBs) at the apoplast, consequently, smaller PBII were observed. Mutated gene in gpa6 was found to encode a Na+/H+ antiporter, OsNHX5. OsNHX5 is expressed in all tissues analyzed, and its expression level is much higher than its closest paralog OsNHX6. The OsNHX5 protein colocalizes to the Golgi, the trans-Golgi network (TGN) and the pre-vacuolar compartment (PVC) in tobacco leaf epidermal cells. In vivo pH measurements indicated that the lumens of Golgi, TGN and PVC became more acidic in gpa6. CONCLUSIONS Our results demonstrated an important role of OsNHX5 in regulating endomembrane luminal pH, which is essential for seed storage protein trafficking in rice.
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Affiliation(s)
- Jianping Zhu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Yulong Ren
- National Key Facility for Crop Resources and Genetic Improvement Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081 People’s Republic of China
| | - Yunlong Wang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Feng Liu
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095 People’s Republic of China
| | - Xuan Teng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Yuanyan Zhang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Erchao Duan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Mingming Wu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Mingsheng Zhong
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Yuanyuan Hao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Xiaopin Zhu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Jie Lei
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Yongfei Wang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Yanfang Yu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Tian Pan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Yiqun Bao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095 People’s Republic of China
| | - Yihua Wang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
| | - Jianmin Wan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095 China
- National Key Facility for Crop Resources and Genetic Improvement Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081 People’s Republic of China
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11
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Zhu X, Pan T, Zhang X, Fan L, Quintero FJ, Zhao H, Su X, Li X, Villalta I, Mendoza I, Shen J, Jiang L, Pardo JM, Qiu QS. K + Efflux Antiporters 4, 5, and 6 Mediate pH and K + Homeostasis in Endomembrane Compartments. PLANT PHYSIOLOGY 2018; 178:1657-1678. [PMID: 30309966 PMCID: PMC6288736 DOI: 10.1104/pp.18.01053] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 10/01/2018] [Indexed: 05/20/2023]
Abstract
KEA4, KEA5, and KEA6 are members of the Arabidopsis (Arabidopsis thaliana) K+ efflux antiporter (KEA) family that share high sequence similarity but whose function remains unknown. Here, we show their gene expression pattern, subcellular localization, and physiological function in Arabidopsis. KEA4, KEA5, and KEA6 had similar tissue expression patterns, and the three KEA proteins localized to the Golgi, the trans-Golgi network, and the prevacuolar compartment/multivesicular bodies, suggesting overlapping roles of these proteins in the endomembrane system. Phenotypic analyses of single, double, and triple mutants confirmed functional redundancy. The triple mutant kea4 kea5 kea6 had small rosettes, short seedlings, and was sensitive to low K+ availability and to the sodicity imposed by high salinity. Also, the kea4 kea5 kea6 mutant plants had a reduced luminal pH in the Golgi, trans-Golgi network, prevacuolar compartment, and vacuole, in accordance with the K/H exchange activity of KEA proteins. Genetic analysis indicated that KEA4, KEA5, and KEA6 as well as endosomal Na+/H+exchanger5 (NHX5) and NHX6 acted coordinately to facilitate endosomal pH homeostasis and salt tolerance. Neither cancelling nor overexpressing the vacuolar antiporters NHX1 and NHX2 in the kea4 kea5 kea6 mutant background altered the salt-sensitive phenotype. The NHX1 and NHX2 proteins in the kea4 kea5 kea6 mutant background could not suppress the acidity of the endomembrane system but brought the vacuolar pH close to wild-type values. Together, these data signify that KEA4, KEA5, and KEA6 are endosomal K+ transporters functioning in maintaining pH and ion homeostasis in the endomembrane network.
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Affiliation(s)
- Xiaojie Zhu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
| | - Ting Pan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
| | - Xiao Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
| | - Ligang Fan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
| | - Francisco J Quintero
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Cientificas, 41092 Seville, Spain
| | - Hong Zhao
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
| | - Xiaomeng Su
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
| | - Xiaojiao Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
| | - Irene Villalta
- Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, 41092 Seville, Spain
| | - Imelda Mendoza
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Cientificas, 41092 Seville, Spain
| | - Jinbo Shen
- School of Life Sciences, Center for Cell and Developmental Biology, and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, Center for Cell and Developmental Biology, and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Jose M Pardo
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Cientificas, 41092 Seville, Spain
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000
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12
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Fan L, Zhao L, Hu W, Li W, Novák O, Strnad M, Simon S, Friml J, Shen J, Jiang L, Qiu QS. Na + ,K + /H + antiporters regulate the pH of endoplasmic reticulum and auxin-mediated development. PLANT, CELL & ENVIRONMENT 2018; 41:850-864. [PMID: 29360148 DOI: 10.1111/pce.13153] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/30/2017] [Accepted: 01/17/2018] [Indexed: 06/07/2023]
Abstract
AtNHX5 and AtNHX6 are endosomal Na+ ,K+ /H+ antiporters that are critical for growth and development in Arabidopsis, but the mechanism behind their action remains unknown. Here, we report that AtNHX5 and AtNHX6, functioning as H+ leak, control auxin homeostasis and auxin-mediated development. We found that nhx5 nhx6 exhibited growth variations of auxin-related defects. We further showed that nhx5 nhx6 was affected in auxin homeostasis. Genetic analysis showed that AtNHX5 and AtNHX6 were required for the function of the endoplasmic reticulum (ER)-localized auxin transporter PIN5. Although AtNHX5 and AtNHX6 were colocalized with PIN5 at ER, they did not interact directly. Instead, the conserved acidic residues in AtNHX5 and AtNHX6, which are essential for exchange activity, were required for PIN5 function. AtNHX5 and AtNHX6 regulated the pH in ER. Overall, AtNHX5 and AtNHX6 may regulate auxin transport across the ER via the pH gradient created by their transport activity. H+ -leak pathway provides a fine-tuning mechanism that controls cellular auxin fluxes.
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Affiliation(s)
- Ligang Fan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Lei Zhao
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Wei Hu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Weina Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Ondřej Novák
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR and Palacký University, Šlechtitelů 27, CZ-78371, Olomouc, Czech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR and Palacký University, Šlechtitelů 27, CZ-78371, Olomouc, Czech Republic
| | - Sibu Simon
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
| | - Jiří Friml
- Institute of Science and Technology (IST) Austria, Am Campus 1, 3400, Klosterneuburg, Austria
| | - Jinbo Shen
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong
| | - Quan-Sheng Qiu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
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13
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Assaha DVM, Ueda A, Saneoka H, Al-Yahyai R, Yaish MW. The Role of Na + and K + Transporters in Salt Stress Adaptation in Glycophytes. Front Physiol 2017; 8:509. [PMID: 28769821 PMCID: PMC5513949 DOI: 10.3389/fphys.2017.00509] [Citation(s) in RCA: 330] [Impact Index Per Article: 47.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 07/03/2017] [Indexed: 12/30/2022] Open
Abstract
Ionic stress is one of the most important components of salinity and is brought about by excess Na+ accumulation, especially in the aerial parts of plants. Since Na+ interferes with K+ homeostasis, and especially given its involvement in numerous metabolic processes, maintaining a balanced cytosolic Na+/K+ ratio has become a key salinity tolerance mechanism. Achieving this homeostatic balance requires the activity of Na+ and K+ transporters and/or channels. The mechanism of Na+ and K+ uptake and translocation in glycophytes and halophytes is essentially the same, but glycophytes are more susceptible to ionic stress than halophytes. The transport mechanisms involve Na+ and/or K+ transporters and channels as well as non-selective cation channels. Thus, the question arises of whether the difference in salt tolerance between glycophytes and halophytes could be the result of differences in the proteins or in the expression of genes coding the transporters. The aim of this review is to seek answers to this question by examining the role of major Na+ and K+ transporters and channels in Na+ and K+ uptake, translocation and intracellular homeostasis in glycophytes. It turns out that these transporters and channels are equally important for the adaptation of glycophytes as they are for halophytes, but differential gene expression, structural differences in the proteins (single nucleotide substitutions, impacting affinity) and post-translational modifications (phosphorylation) account for the differences in their activity and hence the differences in tolerance between the two groups. Furthermore, lack of the ability to maintain stable plasma membrane (PM) potentials following Na+-induced depolarization is also crucial for salt stress tolerance. This stable membrane potential is sustained by the activity of Na+/H+ antiporters such as SOS1 at the PM. Moreover, novel regulators of Na+ and K+ transport pathways including the Nax1 and Nax2 loci regulation of SOS1 expression and activity in the stele, and haem oxygenase involvement in stabilizing membrane potential by activating H+-ATPase activity, favorable for K+ uptake through HAK/AKT1, have been shown and are discussed.
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Affiliation(s)
- Dekoum V. M. Assaha
- Department of Biology, College of Science, Sultan Qaboos UniversityMuscat, Oman
| | - Akihiro Ueda
- Graduate School of Biosphere Science, Hiroshima UniversityHiroshima, Japan
| | - Hirofumi Saneoka
- Graduate School of Biosphere Science, Hiroshima UniversityHiroshima, Japan
| | - Rashid Al-Yahyai
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos UniversityMuscat, Oman
| | - Mahmoud W. Yaish
- Department of Biology, College of Science, Sultan Qaboos UniversityMuscat, Oman
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