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Mori K, Murakoshi Y, Tamura M, Kunitake S, Nishimura K, Ariga H, Tanaka K, Iuchi S, Yotsui I, Sakata Y, Taji T. Mutations in nuclear pore complex promote osmotolerance in Arabidopsis by suppressing the nuclear translocation of ACQOS and its osmotically induced immunity. Front Plant Sci 2024; 15:1304366. [PMID: 38318497 PMCID: PMC10839096 DOI: 10.3389/fpls.2024.1304366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 01/02/2024] [Indexed: 02/07/2024]
Abstract
We have previously reported a wide variation in salt tolerance among Arabidopsis thaliana accessions and identified ACQOS, encoding a nucleotide-binding leucine-rich repeat (NLR) protein, as the causal gene responsible for the disturbance of acquired osmotolerance induced after mild salt stress. ACQOS is conserved among Arabidopsis osmosensitive accessions, including Col-0. In response to osmotic stress, it induces detrimental autoimmunity, resulting in suppression of osmotolerance, but how ACQOS triggers autoimmunity remains unclear. Here, we screened acquired osmotolerance (aot) mutants from EMS-mutagenized Col-0 seeds and isolated the aot19 mutant. In comparison with the wild type (WT), this mutant had acquired osmotolerance and decreased expression levels of pathogenesis-related genes. It had a mutation in a splicing acceptor site in NUCLEOPORIN 85 (NUP85), which encodes a component of the nuclear pore complex. A mutant with a T-DNA insertion in NUP85 acquired osmotolerance similar to aot19. The WT gene complemented the osmotolerant phenotype of aot19. We evaluated the acquired osmotolerance of five nup mutants of outer-ring NUPs and found that nup96, nup107, and aot19/nup85, but not nup43 or nup133, showed acquired osmotolerance. We examined the subcellular localization of the GFP-ACQOS protein and found that its nuclear translocation in response to osmotic stress was suppressed in aot19. We suggest that NUP85 is essential for the nuclear translocation of ACQOS, and the loss-of-function mutation of NUP85 results in acquired osmotolerance by suppressing ACQOS-induced autoimmunity in response to osmotic stress.
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Affiliation(s)
- Kento Mori
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Yusuke Murakoshi
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Masashi Tamura
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Satoru Kunitake
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Kohji Nishimura
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Shimane University, Matsue, Japan
| | - Hirotaka Ariga
- Department of Plant Sciences, Institute of Agrobiological Science, NARO, Tsukuba, Ibaraki, Japan
| | - Keisuke Tanaka
- Nodai Genome Center, Tokyo University of Agriculture, Tokyo, Japan
| | - Satoshi Iuchi
- RIKEN BioResource Research Center, Tsukuba, Ibaraki, Japan
| | - Izumi Yotsui
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Yoichi Sakata
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Teruaki Taji
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
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Fukuda N, Oshima Y, Ariga H, Kajino T, Koyama T, Yaguchi Y, Tanaka K, Yotsui I, Sakata Y, Taji T. ECERIFERUM 10 Encoding an Enoyl-CoA Reductase Plays a Crucial Role in Osmotolerance and Cuticular Wax Loading in Arabidopsis. Front Plant Sci 2022; 13:898317. [PMID: 35812913 PMCID: PMC9259793 DOI: 10.3389/fpls.2022.898317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/30/2022] [Indexed: 05/21/2023]
Abstract
Acquired osmotolerance induced after salt stress is widespread across Arabidopsis thaliana (Arabidopsis) accessions (e.g., Bu-5). However, it remains unclear how this osmotolerance is established. Here, we isolated a mutant showing an acquired osmotolerance-defective phenotype (aod2) from an ion-beam-mutagenized M2 population of Bu-5. aod2 was impaired not only in acquired osmotolerance but also in osmo-shock, salt-shock, and long-term heat tolerances compared with Bu-5, and it displayed abnormal morphology, including small, wrinkled leaves, and zigzag-shaped stems. Genetic analyses of aod2 revealed that a 439-kbp region of chromosome 4 was translocated to chromosome 3 at the causal locus for the osmosensitive phenotype. The causal gene of the aod2 phenotype was identical to ECERIFERUM 10 (CER10), which encodes an enoyl-coenzyme A reductase that is involved in the elongation reactions of very-long-chain fatty acids (VLCFAs) for subsequent derivatization into cuticular waxes, storage lipids, and sphingolipids. The major components of the cuticular wax were accumulated in response to osmotic stress in both Bu-5 WT and aod2. However, less fatty acids, primary alcohols, and aldehydes with chain length ≥ C30 were accumulated in aod2. In addition, aod2 exhibited a dramatic reduction in the number of epicuticular wax crystals on its stems. Endoplasmic reticulum stress mediated by bZIP60 was increased in aod2 under osmotic stress. The only cer10 showed the most pronounced loss of epidermal cuticular wax and most osmosensitive phenotype among four Col-0-background cuticular wax-related mutants. Together, the present findings suggest that CER10/AOD2 plays a crucial role in Arabidopsis osmotolerance through VLCFA metabolism involved in cuticular wax formation and endocytic membrane trafficking.
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Affiliation(s)
- Norika Fukuda
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Yoshimi Oshima
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Hirotaka Ariga
- Plant Resources Unit, Research Center of Genetic Resources, NARO, Ibaraki, Japan
| | - Takuma Kajino
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Takashi Koyama
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Yukio Yaguchi
- Electron Microscope Center, Tokyo University of Agriculture, Tokyo, Japan
| | - Keisuke Tanaka
- Nodai Genome Center, Tokyo University of Agriculture, Tokyo, Japan
| | - Izumi Yotsui
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Yoichi Sakata
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Teruaki Taji
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
- *Correspondence: Teruaki Taji,
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