1
|
Huang J, Tu CY, Wang HY, Zhang Q, Shen RF, Zheng L, Zhu XF. A NAC transcription factor NAC50 regulates Fe reutilization in Arabidopsis under Fe-deficient condition. PHYSIOLOGIA PLANTARUM 2025; 177:e70047. [PMID: 39831318 DOI: 10.1111/ppl.70047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2024] [Accepted: 12/16/2024] [Indexed: 01/30/2025]
Abstract
A lack of iron (Fe) inhibits the growth and development of plants, leading to reduced agricultural yields and quality. In the last ten years, numerous studies have focused on the induction of Fe uptake and translocation under Fe deficiency, but the regulatory mechanisms governing Fe reutilization within plants are still not well understood. Here, we demonstrated the involvement of the NAM/ATAF1/2/CUC2 (NAC) transcription factor NAC50 in response to Fe shortage. The content of soluble Fe was greatly reduced in nac50 mutants, leading to increased chlorosis in the newly emerging leaves under the Fe-deficient condition. Subsequent investigation revealed that the cell wall of the nac50 mutants' roots accumulated more Fe, along with an increment in hemicellulose content, indicating that a cell wall-associated Fe reutilization pathway was involved in the NAC50-regulated Fe insufficiency response. Interestingly, the expression of NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3), a key enzyme in the abscisic acid (ABA) biosynthetic pathway, was down-regulated in the Fe-deficient nac50 mutants, resulting in decreased endogenous ABA level and Fe-deficient sensitive phenotype. Since no direct relationship was observed between NAC50 and NCED3, this suggests a potential role of NAC50 in mediating the ABA accumulation. Moreover, exogenous ABA application in the nac50 mutant restored Fe deficiency resistance to the level observed in wild-type plants (WT), indicating that NAC50 induced the cell wall Fe reutilization potentially through the regulation of ABA accumulation.
Collapse
Affiliation(s)
- Jing Huang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chun Yan Tu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, China
| | - Hao Yu Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, China
| | - Qiang Zhang
- State Key Laboratory of Rice Biology/China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Ren Fang Shen
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lu Zheng
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiao Fang Zhu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
2
|
Ma H, Fu M, Xu Z, Chu Z, Tian J, Wang Y, Zhang X, Han Z, Wu T. Allele-specific expression of AP2-like ABA repressor 1 regulates iron uptake by modulating rhizosphere pH in apple. PLANT PHYSIOLOGY 2024; 196:2121-2136. [PMID: 39197038 DOI: 10.1093/plphys/kiae452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 07/11/2024] [Accepted: 08/09/2024] [Indexed: 08/30/2024]
Abstract
Genetic variation within a species can result in allelic expression for natural selection or breeding efforts. Here, we identified an iron (Fe) deficiency-inducible gene, AP2-like ABA repressor 1 (MdABR1), in apple (Malus domestica). MdABR1 exhibited differential expression at the allelic level (MdABR131A and MdABR131G) in response to Fe deficiency. The W-box insertion in the promoter of MdABR131A is essential for its induced expression and its positive role under Fe deficiency stress. MdABR1 binds to the promoter of basic helix-loop-helix 105 (MdbHLH105), participating in the Fe deficiency response, and activates its transcription. MdABR131A exerts a more pronounced transcriptional activation effect on MdbHLH105. Suppression of MdABR1 expression leads to reduced rhizosphere acidification in apple, and MdABR131A exhibits allelic expression under Fe deficiency stress, which is substantially upregulated and then activates the expression of MdbHLH105, promoting the accumulation of plasma membrane proton ATPase 8 (MdAHA8) transcripts in response to proton extrusion, thereby promoting rhizosphere acidification. Therefore, variation in the ABR1 alleles results in variable gene expression and enables apple plants to exhibit a wider tolerance capability and Fe deficiency response. These findings also shed light on the molecular mechanisms of allele-specific expression in woody plants.
Collapse
Affiliation(s)
- Huaying Ma
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Mengmeng Fu
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Zhen Xu
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Zicheng Chu
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Ji Tian
- Plant Science and Technology College, Beijing University of Agriculture, Beijing 102206, China
| | - Yi Wang
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Xinzhong Zhang
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Zhenhai Han
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Ting Wu
- College of Horticulture, China Agricultural University, Beijing 100193, China
| |
Collapse
|
3
|
Lin M, Liu H, Liu B, Li X, Qian W, Zhou D, Jiang J, Zhang Y. Transcriptome-wide m 6A methylation profile reveals tissue specific regulatory networks in switchgrass (Panicum virgatum L.) under cadmium stress. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:134904. [PMID: 38996680 DOI: 10.1016/j.jhazmat.2024.134904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 05/20/2024] [Accepted: 06/12/2024] [Indexed: 07/14/2024]
Abstract
The heavy metal cadmium (Cd), known for its high toxicity, poses a grave threat to human health through the food chain. N6-methyladenosine (m6A), the most abundant internal modification, regulates plant adaptation to various adversities, yet the panorama of m6A modifications in switchgrass under cadmium stress remains elusive. This study examines the physiological responses of switchgrass roots and shoots exposed to 50 μM CdCl2, alongside an overview of transcriptome-wide m6A methylation patterns. After cadmium treatment, methylation modifications are primarily enriched near stop codons and the 3'UTR region, with a negative correlation between m6A modification and gene expression levels. In shoots, approximately 58 % of DEGs with m6A modifications show upregulation in expression and decrease in m6A peaks, including zinc transporter 4-like (ZIP4). In roots, about 43 % of DEGs with m6A modifications exhibit downregulation in expression and increase in m6A peaks, such as the ABC transporter family member (ABCG25). We further validate the m6A enrichment, gene expression and mRNA stability of ZIP4 in response to Cd treatment. The results suggest that the negative correlation of m6A enrichment and gene expression is due to altered mRNA stability. Our study establishes an m6A regulatory network governing cadmium transport in switchgrass roots and shoots, offering new avenues for candidate gene manipulation in phytoremediation applications of heavy metal pollution.
Collapse
Affiliation(s)
- Mengzhuo Lin
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
| | - Huayue Liu
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
| | - Bowen Liu
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
| | - Xue Li
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
| | - Wenwu Qian
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
| | - Die Zhou
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
| | - Jishan Jiang
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Yunwei Zhang
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China.
| |
Collapse
|
4
|
Zeng H, Chen H, Zhang M, Ding M, Xu F, Yan F, Kinoshita T, Zhu Y. Plasma membrane H +-ATPases in mineral nutrition and crop improvement. TRENDS IN PLANT SCIENCE 2024; 29:978-994. [PMID: 38582687 DOI: 10.1016/j.tplants.2024.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 02/19/2024] [Accepted: 02/22/2024] [Indexed: 04/08/2024]
Abstract
Plasma membrane H+-ATPases (PMAs) pump H+ out of the cytoplasm by consuming ATP to generate a membrane potential and proton motive force for the transmembrane transport of nutrients into and out of plant cells. PMAs are involved in nutrient acquisition by regulating root growth, nutrient uptake, and translocation, as well as the establishment of symbiosis with arbuscular mycorrhizas. Under nutrient stresses, PMAs are activated to pump more H+ and promote organic anion excretion, thus improving nutrient availability in the rhizosphere. Herein we review recent progress in the physiological functions and the underlying molecular mechanisms of PMAs in the efficient acquisition and utilization of various nutrients in plants. We also discuss perspectives for the application of PMAs in improving crop production and quality.
Collapse
Affiliation(s)
- Houqing Zeng
- College of Life and Environmental Sciences, Kharkiv Institute at Hangzhou Normal University, Hangzhou Normal University, Hangzhou 311121, China.
| | - Huiying Chen
- College of Life and Environmental Sciences, Kharkiv Institute at Hangzhou Normal University, Hangzhou Normal University, Hangzhou 311121, China
| | - Maoxing Zhang
- International Research Centre for Environmental Membrane Biology, Department of Horticulture, Foshan University, Foshan 528000, China
| | - Ming Ding
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Feiyun Xu
- Center for Plant Water-Use and Nutrition Regulation, College of JunCao Science and Ecology (College of Carbon Neutrality), Fujian Agriculture and Forestry University, Fuzhou, China
| | - Feng Yan
- Institute of Agronomy and Plant Breeding, Justus Liebig University of Giessen, Giessen, Germany
| | - Toshinori Kinoshita
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya 4660824, Japan.
| | - Yiyong Zhu
- College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
| |
Collapse
|
5
|
Dong W, Liu L, Sun Y, Xu X, Guo G, Heng W, Jiao H, Wei S, Jia B. PbbHLH155 enhances iron deficiency tolerance in pear by directly activating PbFRO2 and PbbHLH38. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 213:108786. [PMID: 38878387 DOI: 10.1016/j.plaphy.2024.108786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 05/28/2024] [Accepted: 05/29/2024] [Indexed: 07/07/2024]
Abstract
Iron (Fe) deficiency is a general stress for many horticulture crops, causing leaf chlorosis and stunted growth. The basic-helix-loop-helix (bHLH) transcription factor (TF) was reported to function in Fe absorption; however, the regulatory mechanism of bHLH genes on iron absorption remains largely unclear in pear. In this study, we found that PbbHLH155 was significantly induced by Fe deficiency. Overexpression of PbbHLH155 in Arabidopsis thaliana and pear calli significantly increases resistance to Fe deficiency. The PbbHLH155-overexpressed Arabidopsis lines exhibited greener leaf color, higher Fe content, stronger Fe chelate reductase (FCR) and root acidification activity. The PbbHLH155 knockout pear calli showed lower Fe content and weaker FCR activity. Interestingly, PbbHLH155 inhibited the expressions of PbFRO2 and PbbHLH38, which were positive regulators in Fe-deficiency responses (FDR). Furthermore, yeast one-hybrid (Y1H) and Dual-Luciferase Reporter (DLR) assays revealed that PbbHLH155 directly binds to the promoters of PbFRO2 and PbbHLH38, thus activating their expression. Overall, our results showed that PbbHLH155 directly promote the expression of PbFRO2 and PbbHLH38 to activate FCR activity for iron absorption. This study provided valuable information for pear breeding.
Collapse
Affiliation(s)
- Weiyu Dong
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
| | - Lun Liu
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
| | - Yu Sun
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
| | - Xiaoqian Xu
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
| | - Guoling Guo
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
| | - Wei Heng
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
| | - Huijun Jiao
- Shandong Fresh Pear Cultivation and Breeding Engineering Technology Research Center, Shandong Institute of Pomology, Taian, 271000, China.
| | - Shuwei Wei
- Shandong Fresh Pear Cultivation and Breeding Engineering Technology Research Center, Shandong Institute of Pomology, Taian, 271000, China.
| | - Bing Jia
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
| |
Collapse
|
6
|
Wang S, Dong L, Yao W, Jiang T. PagbHLH35 Enhances Salt Tolerance through Improving ROS Scavenging in Transgenic Poplar. PLANTS (BASEL, SWITZERLAND) 2024; 13:1835. [PMID: 38999675 PMCID: PMC11244237 DOI: 10.3390/plants13131835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Revised: 06/29/2024] [Accepted: 07/01/2024] [Indexed: 07/14/2024]
Abstract
The bHLH transcription factor family plays crucial roles in plant growth and development and their responses to adversity. In this study, a highly salt-induced bHLH gene, PagbHLH35 (Potri.018G141600), was identified from Populus alba × P. glandullosa (84K poplar). PagbHLH35 contains a highly conserved bHLH domain within the region of 52-114 amino acids. A subcellular localization result confirmed its nuclear localization. A yeast two-hybrid assay indicated PagbHLH35 lacks transcriptional activation activity, while a yeast one-hybrid assay indicated it could specifically bind to G-box and E-box elements. The expression of PagbHLH35 reached its peak at 12 h and 36 h time points under salt stress in the leaves and roots, respectively. A total of three positive transgenic poplar lines overexpressing PagbHLH35 were generated via Agrobacterium-mediated leaf disk transformation. Under NaCl stress, the transgenic poplars exhibited significantly enhanced morphological and physiological advantages such as higher POD activity, SOD activity, chlorophyll content, and proline content, and lower dehydration rate, MDA content and hydrogen peroxide (H2O2) content, compared to wild-type (WT) plants. In addition, histological staining showed that there was lower ROS accumulation in the transgenic poplars under salt stress. Moreover, the relative expression levels of several antioxidant genes in the transgenic poplars were significantly higher than those in the WT. All the results indicate that PagbHLH35 can improve salt tolerance by enhancing ROS scavenging in transgenic poplars.
Collapse
Affiliation(s)
- Shuang Wang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (S.W.); (L.D.); (W.Y.)
| | - Liben Dong
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (S.W.); (L.D.); (W.Y.)
- Harbin Research Institute of Forestry Machinery, State Administration of Forestry and Grassland, Harbin 150086, China
- Research Centre of Cold Temperate Forestry, Chinese Academy of Forestry, Harbin 150086, China
| | - Wenjing Yao
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (S.W.); (L.D.); (W.Y.)
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, 159 Longpan Road, Nanjing 210037, China
| | - Tingbo Jiang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (S.W.); (L.D.); (W.Y.)
| |
Collapse
|
7
|
Lei P, Jiang Y, Zhao Y, Jiang M, Ji X, Ma L, Jin G, Li J, Zhang S, Kong D, Zhao X, Meng F. Functions of Basic Helix-Loop-Helix (bHLH) Proteins in the Regulation of Plant Responses to Cold, Drought, Salt, and Iron Deficiency: A Comprehensive Review. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:10692-10709. [PMID: 38712500 DOI: 10.1021/acs.jafc.3c09665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Abiotic stresses including cold, drought, salt, and iron deficiency severely impair plant development, crop productivity, and geographic distribution. Several bodies of research have shed light on the pleiotropic functions of BASIC HELIX-LOOP-HELIX (bHLH) proteins in plant responses to these abiotic stresses. In this review, we mention the regulatory roles of bHLH TFs in response to stresses such as cold, drought, salt resistance, and iron deficiency, as well as in enhancing grain yield in plants, especially crops. The bHLH proteins bind to E/G-box motifs in the target promoter and interact with various other factors to form a complex regulatory network. Through this network, they cooperatively activate or repress the transcription of downstream genes, thereby regulating various stress responses. Finally, we present some perspectives for future research focusing on the molecular mechanisms that integrate and coordinate these abiotic stresses. Understanding these molecular mechanisms is crucial for the development of stress-tolerant crops.
Collapse
Affiliation(s)
- Pei Lei
- Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China
| | - Yaxuan Jiang
- College of Life Science, Northeast Forestry University, Hexing Road 26, Harbin 150040, China
| | - Yong Zhao
- College of Life Sciences, Baicheng Normal University, Baicheng 137099, China
| | - Mingquan Jiang
- Jilin Province Product Quality Supervision and Inspection Institute, Changchun 130022, China
| | - Ximei Ji
- Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China
- College of Life Science, Northeast Forestry University, Hexing Road 26, Harbin 150040, China
| | - Le Ma
- College of Life Science, Northeast Forestry University, Hexing Road 26, Harbin 150040, China
| | - Guangze Jin
- College of Life Science, Northeast Forestry University, Hexing Road 26, Harbin 150040, China
| | - Jianxin Li
- College of Life Science, Northeast Forestry University, Hexing Road 26, Harbin 150040, China
| | - Subin Zhang
- College of Life Science, Northeast Forestry University, Hexing Road 26, Harbin 150040, China
| | - Dexin Kong
- College of Life Science, Northeast Forestry University, Hexing Road 26, Harbin 150040, China
| | - Xiyang Zhao
- Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China
| | - Fanjuan Meng
- Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China
| |
Collapse
|
8
|
Zhang Z, Cheng J, Wang W, Gao Y, Xian X, Li C, Wang Y. Transcription factors dealing with Iron-deficiency stress in plants: focus on the bHLH transcription factor family. PHYSIOLOGIA PLANTARUM 2023; 175:e14091. [PMID: 38148182 DOI: 10.1111/ppl.14091] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 10/16/2023] [Accepted: 10/24/2023] [Indexed: 12/28/2023]
Abstract
Iron (Fe), as an important micronutrient element necessary for plant growth and development, not only participates in multiple physiological and biochemical reactions in cells but also exerts a crucial role in respiration and photosynthetic electron transport. Since Fe is mainly present in the soil in the form of iron hydroxide, Fe deficiency exists universally in plants and has become an important factor triggering crop yield reduction and quality decline. It has been shown that transcription factors (TFs), as an important part of plant signaling pathways, not only coordinate the internal signals of different interaction partners during plant development, but also participate in plant responses to biological and abiotic stresses, such as Fe deficiency stress. Here, the role of bHLH transcription factors in the regulation of Fe homeostasis (mainly Fe uptake) is discussed with emphasis on the functions of MYB, WRKY and other TFs in the maintenance of Fe homeostasis. This review provides a theoretical basis for further studies on the regulation of TFs in Fe deficiency stress response.
Collapse
Affiliation(s)
- Zhongxing Zhang
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Jiao Cheng
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Wanxia Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Yanlong Gao
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Xulin Xian
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Cailong Li
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Yanxiu Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| |
Collapse
|
9
|
Li X, Cao H, Yu D, Xu K, Zhang Y, Shangguan X, Zheng X, Yang Z, Li C, Pan X, Cui Y, Zhang Z, Han M, Zhang Y, Sun Q, Guo H, Zhao J, Li L, Li C. SlbHLH152, a bHLH transcription factor positively regulates iron homeostasis in tomato. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 335:111821. [PMID: 37558055 DOI: 10.1016/j.plantsci.2023.111821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 08/03/2023] [Accepted: 08/05/2023] [Indexed: 08/11/2023]
Abstract
The maintain of iron (Fe) homeostasis is essential for plant survival. In tomato, few transcription factors have been identified as regulators of Fe homeostasis, among which SlbHLH068 induced by iron deficiency, plays an important role. However, the upstream regulator(s) responsible for activating the expression of SlbHLH068 remain(s) unknown. In this study, the bHLH (basic helix-loop-helix) transcription factor SlbHLH152 was identified as an upstream regulator of SlbHLH068 using yeast one-hybrid screening. Deletion of SlbHLH152 led to a significant decline in Fe concentration, which was accompanied by reduced expression of Fe-deficiency-responsive genes. In contrast, SlbHLH152 overexpression plants displayed tolerance to iron deficiency, increased Fe accumulation, and elevated expression of Fe-deficiency-responsive genes. Further analysis indicated that SlbHLH152 directly activates the transcription of SlbHLH068. Taken together, our results suggest that SlbHLH152 may be involved in the regulation of iron homeostasis by directly activating the transcription of SlbHLH068 in tomato.
Collapse
Affiliation(s)
- Xiaoli Li
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Haohao Cao
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Deshui Yu
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Kedong Xu
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Yi Zhang
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Xinxin Shangguan
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Xiaohong Zheng
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Zhongzhou Yang
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China
| | - Chaoqiong Li
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Xingchen Pan
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Yiming Cui
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Zhiqing Zhang
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Mengru Han
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Yiqing Zhang
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Qimeng Sun
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Huiling Guo
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Jingyi Zhao
- College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China
| | - Lili Li
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China; College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, China.
| | - Chengwei Li
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001, China; College of Bioengineering, Henan University of Technology, Zhengzhou 450001, China.
| |
Collapse
|
10
|
Sun Q, Zhao D, Gao M, Wu Y, Zhai L, Sun S, Wu T, Zhang X, Xu X, Han Z, Wang Y. MxMPK6-2-mediated phosphorylation enhances the response of apple rootstocks to Fe deficiency by activating PM H + -ATPase MxHA2. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 116:69-86. [PMID: 37340905 DOI: 10.1111/tpj.16360] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 06/22/2023]
Abstract
Iron (Fe) deficiency significantly affects the growth and development, fruit yield and quality of apples. Apple roots respond to Fe deficiency stress by promoting H+ secretion, which acidifies the soil. In this study, the plasma membrane (PM) H+ -ATPase MxHA2 promoted H+ secretion and root acidification of apple rootstocks under Fe deficiency stress. H+ -ATPase MxHA2 is upregulated in Fe-efficient apple rootstock of Malus xiaojinensis at the transcription level. Fe deficiency also induced kinase MxMPK6-2, a positive regulator in Fe absorption that can interact with MxHA2. However, the mechanism involving these two factors under Fe deficiency stress is unclear. MxMPK6-2 overexpression in apple roots positively regulated PM H+ -ATPase activity, thus enhancing root acidification under Fe deficiency stress. Moreover, co-expression of MxMPK6-2 and MxHA2 in apple rootstocks further enhanced PM H+ -ATPase activity under Fe deficiency. MxMPK6-2 phosphorylated MxHA2 at the Ser909 site of C terminus, Thr320 and Thr412 sites of the Central loop region. Phosphorylation at the Ser909 and Thr320 promoted PM H+ -ATPase activity, while phosphorylation at Thr412 inhibited PM H+ -ATPase activity. MxMPK6-2 also phosphorylated the Fe deficiency-induced transcription factor MxbHLH104 at the Ser169 site, which then could bind to the promoter of MxHA2, thus enhancing MxHA2 upregulation. In conclusion, the MAP kinase MxMPK6-2-mediated phosphorylation directly and indirectly regulates PM H+ -ATPase MxHA2 activity at the protein post-translation and transcription levels, thus synergistically enhancing root acidification under Fe deficiency stress.
Collapse
Affiliation(s)
- Qiran Sun
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Danrui Zhao
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Min Gao
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Yue Wu
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Longmei Zhai
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Shan Sun
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Ting Wu
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Xinzhong Zhang
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Xuefeng Xu
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Zhenhai Han
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| | - Yi Wang
- College of Horticulture, China Agricultural University, Beijing, 100193, People's Republic of China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture and Rural Affairs, Beijing, 100193, People's Republic of China
| |
Collapse
|
11
|
Radani Y, Li R, Korboe HM, Ma H, Yang L. Transcriptional and Post-Translational Regulation of Plant bHLH Transcription Factors during the Response to Environmental Stresses. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12112113. [PMID: 37299095 DOI: 10.3390/plants12112113] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/16/2023] [Accepted: 05/19/2023] [Indexed: 06/12/2023]
Abstract
Over the past decades, extensive research has been conducted to identify and characterize various plant transcription factors involved in abiotic stress responses. Therefore, numerous efforts have been made to improve plant stress tolerance by engineering these transcription factor genes. The plant basic Helix-Loop-Helix (bHLH) transcription factor family represents one of the most prominent gene families and contains a bHLH motif that is highly conserved in eukaryotic organisms. By binding to specific positions in promoters, they activate or repress the transcription of specific response genes and thus affect multiple variables in plant physiology such as the response to abiotic stresses, which include drought, climatic variations, mineral deficiencies, excessive salinity, and water stress. The regulation of bHLH transcription factors is crucial to better control their activity. On the one hand, they are regulated at the transcriptional level by other upstream components; on the other hand, they undergo various modifications such as ubiquitination, phosphorylation, and glycosylation at the post-translational level. Modified bHLH transcription factors can form a complex regulatory network to regulate the expression of stress response genes and thus determine the activation of physiological and metabolic reactions. This review article focuses on the structural characteristics, classification, function, and regulatory mechanism of bHLH transcription factor expression at the transcriptional and post-translational levels during their responses to various abiotic stress conditions.
Collapse
Affiliation(s)
- Yasmina Radani
- State Key Laboratory of Tree Genetics and Breeding, Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Rongxue Li
- State Key Laboratory of Tree Genetics and Breeding, Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Harriet Mateko Korboe
- State Key Laboratory of Tree Genetics and Breeding, Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Hongyu Ma
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Liming Yang
- State Key Laboratory of Tree Genetics and Breeding, Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| |
Collapse
|
12
|
Ding Y, Wang X, Wang D, Jiang L, Xie J, Wang T, Song L, Zhao X. Identification of CmbHLH Transcription Factor Family and Excavation of CmbHLHs Resistant to Necrotrophic Fungus Alternaria in Chrysanthemum. Genes (Basel) 2023; 14:genes14020275. [PMID: 36833202 PMCID: PMC9957535 DOI: 10.3390/genes14020275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/15/2023] [Accepted: 01/16/2023] [Indexed: 01/22/2023] Open
Abstract
Chrysanthemum morifolium Ramat. 'Huaihuang' is a traditional Chinese medicinal plant. However, a black spot disease caused by Alternaria sp., a typical necrotrophic fungus, has a serious damaging influence on the field growth, yield, and quality of the plant. 'Huaiju 2#' being bred from 'Huaihuang', shows resistance to Alternaria sp. bHLH transcription factor has been widely studied because of their functions in growth development, signal transduction, and abiotic stress. However, the function of bHLH in biotic stress has rarely been studied. To characterize the resistance genes, the CmbHLH family was surveyed in 'Huaiju 2#'. On the basis of the transcriptome database of 'Huaiju 2#' after Alternaria sp. inoculation, with the aid of the Chrysanthemum genome database, 71 CmbHLH genes were identified and divided into 17 subfamilies. Most (64.8%) of the CmbHLH proteins were rich in negatively charged amino acids. CmbHLH proteins are generally hydrophilic proteins with a high aliphatic amino acid content. Among the 71 CmbHLH proteins, five CmbHLHs were significantly upregulated by Alternaria sp. infection, and the expression of CmbHLH18 was the most significant. Furthermore, heterologous overexpression of CmbHLH18 could improve the resistance of Arabidopsis thaliana to necrotrophic fungus Alternaria brassicicola by enhancing callose deposition, preventing spores from entering leaves, reducing ROS accumulation, increasing the activities of antioxidant enzymes and defense enzymes, and promoting their gene expression levels. These results indicate that the five CmbHLHs, especially CmbHLH18, may be considered candidate genes for resistance to necrotrophic fungus. These findings not only increase our understanding of the role CmbHLHs play in biotic stress but also provide a basis by using CmbHLHs to breed a new variety of Chrysanthemum with high resistance to necrotrophic fungus.
Collapse
Affiliation(s)
- Yifeng Ding
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Xiaomeng Wang
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Dandan Wang
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Liwei Jiang
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Jing Xie
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Tianle Wang
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Lingyu Song
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Xiting Zhao
- Department of Biological Sciences, College of Life Sciences, Henan Normal University, Xinxiang 453007, China
- Engineering Technology Research Center of Nursing and Utilization of Genuine Chinese Crude Drugs in Henan Province, Xinxiang 453007, China
- Engineering Laboratory of Biotechnology for Green Medicinal Plant of Henan Province, Xinxiang 453007, China
- Correspondence: or ; Tel.: +86-182-3739-1085 or +86-135-6988-6182
| |
Collapse
|
13
|
Zhu L, Yang J, Zhang Y, Hu H, Cui J, Xue J, Xu J. Overexpression of CfICE1 from Cryptomeria fortunei Enhances Cold, Drought and Salt Stress in Poplar. Int J Mol Sci 2022; 23:ijms232315214. [PMID: 36499538 PMCID: PMC9736380 DOI: 10.3390/ijms232315214] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/21/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
ICE1, a regulator of the cold-inducible transcriptome and freezing tolerance, is currently widely believed to be involved in plant resistance to cold stress. In this study, CfICE1 from Cryptomeria fortunei was transformed into poplar. Physiological indicators of transgenic, empty vector and wild-type poplar after abiotic stress (cold, drought and salt) were determined. Transgenic lines had a higher chlorophyll content, antioxidant enzyme activity and soluble protein content, as well as a lower malondialdehyde and hydrogen peroxide content. The ultrastructure of the plant was observed by transmission electron microscopy, and after stress, the cell structure of the transgenic line was more complete than that of the wild type. CfICE1 was upregulated in transgenic poplar trees after abiotic stress (cold, drought and salt). The CfICE1 transgenic plants improved plant resistance by regulating the CBF gene of poplar under cold and salt stress. In terms of plant responses to abiotic stress, this study showed that overexpression of CfICE1 improved the cold, drought and salt tolerance of poplars.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Jin Xu
- Correspondence: ; Tel.: +86-138-1383-1609
| |
Collapse
|
14
|
Noor I, Sohail H, Sun J, Nawaz MA, Li G, Hasanuzzaman M, Liu J. Heavy metal and metalloid toxicity in horticultural plants: Tolerance mechanism and remediation strategies. CHEMOSPHERE 2022; 303:135196. [PMID: 35659937 DOI: 10.1016/j.chemosphere.2022.135196] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 04/30/2022] [Accepted: 05/31/2022] [Indexed: 05/27/2023]
Abstract
Heavy metal/metalloids (HMs) are among the primary soil pollutants that limit crop production worldwide. Plants grown in HM contaminated soils exhibit reduced growth and development, resulting in a decrease in crop production. The exposure to HMs induces plant oxidative stress due to the formation of free radicals, which alter plant morphophysiological and biochemical mechanisms at cellular and tissue levels. When exposed to HM toxicity, plants evolve sophisticated physiological and cellular defense strategies, such as sequestration and transportation of metals, to ensure their survival. Plants also have developed efficient strategies by activating signaling pathways, which induce the expression of HM transporters. Plants either avoid the uptake of HMs from the soil or activate the detoxifying mechanism to tolerate HM stress, which involves the production of antioxidants (enzymatic and non-enzymatic) for the scavenging of reactive oxygen species. The metal-binding proteins including phytochelatins and metallothioneins also participate in metal detoxification. Furthermore, phytohormones and their signaling pathways also help to regulate cellular activities to counteract HM stress. The excessive levels of HMs in the soil can contribute to plant morpho-physiological, biochemical, and molecular alterations, which have a detrimental effect on the quality and productivity of crops. To maintain the commercial value of fruits and vegetables, various measures should be considered to remove HMs from the metal-polluted soils. Bioremediation is a promising approach that involves the use of tolerant microorganisms and plants to manage HMs pollution. The understanding of HM toxicity, signaling pathways, and tolerance mechanisms will facilitate the development of new crop varieties that help in improving phytoremediation.
Collapse
Affiliation(s)
- Iqra Noor
- Key Laboratory of Horticultural Plant Biology-Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Hamza Sohail
- Key Laboratory of Horticultural Plant Biology-Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Jingxian Sun
- Key Laboratory of Horticultural Plant Biology-Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Muhammad Azher Nawaz
- Department of Horticulture, College of Agriculture, University of Sargodha, Sargodha, 40100, Pakistan
| | - Guohuai Li
- Key Laboratory of Horticultural Plant Biology-Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Mirza Hasanuzzaman
- Department of Agronomy, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka, 1207, Bangladesh.
| | - Junwei Liu
- Key Laboratory of Horticultural Plant Biology-Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, PR China.
| |
Collapse
|
15
|
Qian Y, Zhang T, Yu Y, Gou L, Yang J, Xu J, Pi E. Regulatory Mechanisms of bHLH Transcription Factors in Plant Adaptive Responses to Various Abiotic Stresses. FRONTIERS IN PLANT SCIENCE 2021; 12:677611. [PMID: 34220896 PMCID: PMC8250158 DOI: 10.3389/fpls.2021.677611] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/19/2021] [Indexed: 05/05/2023]
Abstract
Basic helix-loop-helix proteins (bHLHs) comprise one of the largest families of transcription factors in plants. They have been shown to be involved in responses to various abiotic stresses, such as drought, salinity, chilling, heavy metal toxicity, iron deficiency, and osmotic damages. By specifically binding to cis-elements in the promoter region of stress related genes, bHLHs can regulate their transcriptional expression, thereby regulating the plant's adaptive responses. This review focuses on the structural characteristics of bHLHs, the regulatory mechanism of how bHLHs are involved transcriptional activation, and the mechanism of how bHLHs regulate the transcription of target genes under various stresses. Finally, as increasing research demonstrates that flavonoids are usually induced under fluctuating environments, the latest research progress and future research prospects are described on the mechanisms of how flavonoid biosynthesis is regulated by bHLHs in the regulation of the plant's responses to abiotic stresses.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Erxu Pi
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| |
Collapse
|
16
|
Current Understanding of bHLH Transcription Factors in Plant Abiotic Stress Tolerance. Int J Mol Sci 2021; 22:ijms22094921. [PMID: 34066424 PMCID: PMC8125693 DOI: 10.3390/ijms22094921] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/28/2021] [Accepted: 05/01/2021] [Indexed: 01/20/2023] Open
Abstract
Named for the characteristic basic helix-loop-helix (bHLH) region in their protein structure, bHLH proteins are a widespread transcription factor class in eukaryotes. bHLHs transcriptionally regulate their target genes by binding to specific positions on their promoters and thereby direct a variety of plant developmental and metabolic processes, such as photomorphogenesis, flowering induction, shade avoidance, and secondary metabolite biosynthesis, which are important for promoting plant tolerance or adaptation to adverse environments. In this review, we discuss the vital roles of bHLHs in plant responses to abiotic stresses, such as drought, salinity, cold, and iron deficiency. We suggest directions for future studies into the roles of bHLH genes in plant and discuss their potential applications in crop breeding.
Collapse
|
17
|
Gao F, Dubos C. Transcriptional integration of plant responses to iron availability. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:2056-2070. [PMID: 33246334 DOI: 10.1093/jxb/eraa556] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 05/16/2023]
Abstract
Iron is one of the most important micronutrients for plant growth and development. It functions as the enzyme cofactor or component of electron transport chains in various vital metabolic processes, including photosynthesis, respiration, and amino acid biosynthesis. To maintain iron homeostasis, and therefore prevent any deficiency or excess that could be detrimental, plants have evolved complex transcriptional regulatory networks to tightly control iron uptake, translocation, assimilation, and storage. These regulatory networks are composed of various transcription factors; among them, members of the basic helix-loop-helix (bHLH) family play an essential role. Here, we first review recent advances in understanding the roles of bHLH transcription factors involved in the regulatory cascade controlling iron homeostasis in the model plant Arabidopsis, and extend this understanding to rice and other plant species. The importance of other classes of transcription factors will also be discussed. Second, we elaborate on the post-translational mechanisms involved in the regulation of these regulatory networks. Finally, we provide some perspectives on future research that should be conducted in order to precisely understand how plants control the homeostasis of this micronutrient.
Collapse
Affiliation(s)
- Fei Gao
- BPMP, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Christian Dubos
- BPMP, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| |
Collapse
|
18
|
Li D, Sun Q, Zhang G, Zhai L, Li K, Feng Y, Wu T, Zhang X, Xu X, Wang Y, Han Z. MxMPK6-2-bHLH104 interaction is involved in reactive oxygen species signaling in response to iron deficiency in apple rootstock. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:1919-1932. [PMID: 33216933 DOI: 10.1093/jxb/eraa547] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 11/15/2020] [Indexed: 05/16/2023]
Abstract
Iron (Fe) is a trace element necessary for plant growth. Many land plants have evolved a set of mechanisms associated with the Fe absorption process to deal with the problem of insufficient Fe supply in the soil. During Fe absorption, reactive oxygen species (ROS) can be used as a signal to initiate a response to stress caused by Fe deficiency. However, the molecular mechanisms underlying the involvement of ROS in the Fe deficiency stress response remains unclear. In this study, we have identified a kinase, MxMPK6-2, from Malus xiaojinensis, an apple rootstock that is highly efficient at Fe absorption. MxMPK6-2 has been shown to be responsive to ROS signals during Fe deficiency, and MxMPK6-2 overexpression in apple calli enhanced its tolerance to Fe deficiency. We further screened for proteins in the Fe absorption pathway and identified MxbHLH104, a transcription factor which interacts with MxMPK6-2. MxbHLH104 can be phosphorylated by MxMPK6-2 in vivo, and we confirmed that its phosphorylation increased Fe absorption in apple calli under Fe deficiency, with the presence of ROS promoting this process. Overall, we have demonstrated that MxMPK6-2 is responsive to ROS signaling during Fe deficiency, and is able to control its response by regulating MxbHLH104.
Collapse
Affiliation(s)
- Duyue Li
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Qiran Sun
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Guifen Zhang
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Longmei Zhai
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Keting Li
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Yi Feng
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Ting Wu
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Xinzhong Zhang
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Xuefeng Xu
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Yi Wang
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| | - Zhenhai Han
- College of Horticulture, China Agricultural University, Beijing, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Ministry of Agriculture, Beijing, P. R. China
| |
Collapse
|
19
|
Qiu JR, Huang Z, Xiang XY, Xu WX, Wang JT, Chen J, Song L, Xiao Y, Li X, Ma J, Cai SZ, Sun LX, Jiang CZ. MfbHLH38, a Myrothamnus flabellifolia bHLH transcription factor, confers tolerance to drought and salinity stresses in Arabidopsis. BMC PLANT BIOLOGY 2020; 20:542. [PMID: 33267774 PMCID: PMC7709435 DOI: 10.1186/s12870-020-02732-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 11/09/2020] [Indexed: 05/08/2023]
Abstract
BACKGROUND The basic helix-loop-helix (bHLH) proteins, a large transcription factors family, are involved in plant growth and development, and defensive response to various environmental stresses. The resurrection plant Myrothamnus flabellifolia is known for its extremely strong drought tolerance, but few bHLHs taking part in abiotic stress response have been unveiled in M. flabellifolia. RESULTS In the present research, we cloned and characterized a dehydration-inducible gene, MfbHLH38, from M. flabellifolia. The MfbHLH38 protein is localized in the nucleus, where it may act as a transcription factor. Heterologous expression of MfbHLH38 in Arabidopsis improved the tolerance to drought and salinity stresses, as determined by the studies on physiological indexes, such as contents of chlorophyll, malondialdehyde (MDA), proline (Pro), soluble protein, and soluble sugar, water loss rate of detached leaves, reactive oxygen species (ROS) accumulation, as well as antioxidant enzyme activities. Besides, MfbHLH38 overexpression increased the sensitivity of stomatal closure to mannitol and abscisic acid (ABA), improved ABA level under drought stress, and elevated the expression of genes associated with ABA biosynthesis and ABA responding, sucha as NCED3, P5CS, and RD29A. CONCLUSIONS Our results presented evidence that MfbHLH38 enhanced tolerance to drought and salinity stresses in Arabidopsis through increasing water retention ability, regulating osmotic balance, decreasing stress-induced oxidation damage, and possibly participated in ABA-dependent stress-responding pathway.
Collapse
Affiliation(s)
- Jia-Rui Qiu
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Zhuo Huang
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China.
| | - Xiang-Ying Xiang
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Wen-Xin Xu
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Jia-Tong Wang
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Jia Chen
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Li Song
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Yao Xiao
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Xi Li
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Jun Ma
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Shi-Zhen Cai
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Ling-Xia Sun
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China
| | - Cai-Zhong Jiang
- Department of Plant Sciences, University of California Davis, Davis, CA, 95616, USA
- Crops Pathology and Genetics Research Unit, United States Department of Agriculture, Agricultural Research Service, Davis, CA, 95616, USA
| |
Collapse
|
20
|
Chen J, Zhang NN, Pan Q, Lin XY, Shangguan Z, Zhang JH, Wei GH. Hydrogen sulphide alleviates iron deficiency by promoting iron availability and plant hormone levels in Glycine max seedlings. BMC PLANT BIOLOGY 2020; 20:383. [PMID: 32819279 PMCID: PMC7441670 DOI: 10.1186/s12870-020-02601-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 08/16/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Hydrogen sulphide (H2S) is involved in regulating physiological processes in plants. We investigated how H2S ameliorates iron (Fe) deficiency in soybean (Glycine max L.) seedlings. Multidisciplinary approaches including physiological, biochemical and molecular, and transcriptome methods were used to investigate the H2S role in regulating Fe availability in soybean seedlings. RESULTS Our results showed that H2S completely prevented leaf interveinal chlorosis and caused an increase in soybean seedling biomass under Fe deficiency conditions. Moreover, H2S decreased the amount of root-bound apoplastic Fe and increased the Fe content in leaves and roots by regulating the ferric-chelate reductase (FCR) activities and Fe homeostasis- and sulphur metabolism-related gene expression levels, thereby promoting photosynthesis in soybean seedlings. In addition, H2S changed the plant hormone concentrations by modulating plant hormone-related gene expression abundances in soybean seedlings grown in Fe-deficient solution. Furthermore, organic acid biosynthesis and related genes expression also played a vital role in modulating the H2S-mediated alleviation of Fe deficiency in soybean seedlings. CONCLUSION Our results indicated that Fe deficiency was alleviated by H2S through enhancement of Fe acquisition and assimilation, thereby regulating plant hormones and organic acid synthesis in plants.
Collapse
Affiliation(s)
- Juan Chen
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China.
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, the Chinese University of Hong Kong, Shatin, Hong Kong.
| | - Ni-Na Zhang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China
| | - Qing Pan
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China
| | - Xue-Yuan Lin
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China
| | - Zhouping Shangguan
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China
| | - Jian-Hua Zhang
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, the Chinese University of Hong Kong, Shatin, Hong Kong
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong
| | - Ge-Hong Wei
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China.
| |
Collapse
|
21
|
Li YY, Sui XY, Yang JS, Xiang XH, Li ZQ, Wang YY, Zhou ZC, Hu RS, Liu D. A novel bHLH transcription factor, NtbHLH1, modulates iron homeostasis in tobacco (Nicotiana tabacum L.). Biochem Biophys Res Commun 2020; 522:233-239. [PMID: 31757426 DOI: 10.1016/j.bbrc.2019.11.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 11/10/2019] [Indexed: 01/05/2023]
Abstract
Iron (Fe) is a major micronutrient which influences plant growth, development, quality and yield. Although basic helix-loop-helix (bHLH) transcription factors (TFs) which respond to iron deficiency have been identified, the molecular mechanisms have not been fully elucidated. In this study, a novel bHLH TF, NtbHLH1, was found to be induced by iron deficiency. Further analysis indicated that NtbHLH1 is localized to the nucleus and functions as a transcriptional activator. Moreover, overexpression of NtbHLH1 resulted in longer roots, altered rhizosphere pH and increased ferric-chelate reductase activity in iron deficient conditions. Overall these changes resulted in increased iron uptake relative to wild type plants. NtbHLH1 mutants, on the other hand, had an opposite phenotype. In addition, transcript levels of seven genes associated with iron deficiency response were higher in the NtbHLH1 overexpression transgenic plants and lower in ntbhlh1 relative to the WT under iron deficiency treatment. Taken together, these results demonstrated that NtbHLH1 plays a key role in iron deficiency response and they provide new insights into the molecular basis of iron homeostasis in tobacco.
Collapse
Affiliation(s)
- Yang-Yang Li
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China; Hunan Tobacco Research Institute, Changsha, 410004, China.
| | - Xiao-Yan Sui
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China; State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Hunan Academy of Agricultural Sciences, Changsha, 410125, China.
| | - Jia-Shuo Yang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China; Hunan Tobacco Research Institute, Changsha, 410004, China.
| | - Xiao-Hua Xiang
- Hainan Cigar Research Institution, Haikou, 571100, Hainan, China.
| | - Zun-Qiang Li
- Mudanjiang Tobacco Science Research Institute, Harbin, 150010, China.
| | - Yuan-Ying Wang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China.
| | - Zhi-Cheng Zhou
- Hunan Tobacco Research Institute, Changsha, 410004, China.
| | - Ri-Sheng Hu
- Hunan Tobacco Research Institute, Changsha, 410004, China.
| | - Dan Liu
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China.
| |
Collapse
|
22
|
Wang M, Kawakami Y, Bhullar NK. Molecular Analysis of Iron Deficiency Response in Hexaploid Wheat. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2019. [DOI: 10.3389/fsufs.2019.00067] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
|
23
|
A key gene bHLH115 in iron homeostasis: comprehensive bioinformatics analyses in Arabidopsis, tomato, rice, and maize. Biometals 2019; 32:641-656. [DOI: 10.1007/s10534-019-00199-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 04/30/2019] [Indexed: 10/26/2022]
|
24
|
Zhou LJ, Zhang CL, Zhang RF, Wang GL, Li YY, Hao YJ. The SUMO E3 Ligase MdSIZ1 Targets MdbHLH104 to Regulate Plasma Membrane H +-ATPase Activity and Iron Homeostasis. PLANT PHYSIOLOGY 2019; 40:2068-2080. [PMID: 30333149 DOI: 10.1111/pce.12978] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 04/04/2017] [Accepted: 04/08/2017] [Indexed: 05/20/2023]
Abstract
SIZ1 (a SIZ/PIAS-type SUMO E3 ligase)-mediated small ubiquitin-like modifier (SUMO) modification of target proteins is important for various biological processes related to abiotic stress resistance in plants; however, little is known about its role in resistance toward iron (Fe) deficiency. Here, the SUMO E3 ligase MdSIZ1 was shown to be involved in the plasma membrane (PM) H+-ATPase-mediated response to Fe deficiency. Subsequently, a basic helix-loop-helix transcription factor, MdbHLH104 (a homolog of Arabidopsis bHLH104 in apple), which acts as a key component in regulating PM H+-ATPase-mediated rhizosphere acidification and Fe uptake in apples (Malus domestica), was identified as a direct target of MdSIZ1. MdSIZ1 directly sumoylated MdbHLH104 both in vitro and in vivo, especially under conditions of Fe deficiency, and this sumoylation was required for MdbHLH104 protein stability. Double substitution of K139R and K153R in MdbHLH104 blocked MdSIZ1-mediated sumoylation in vitro and in vivo, indicating that the K139 and K153 residues were the principal sites of SUMO conjugation. Moreover, the transcript level of the MdSIZ1 gene was substantially induced following Fe deficiency. MdSIZ1 overexpression exerted a positive influence on PM H+-ATPase-mediated rhizosphere acidification and Fe uptake. Our findings reveal an important role for sumoylation in the regulation of PM H+-ATPase-mediated rhizosphere acidification and Fe uptake during Fe deficiency in plants.
Collapse
Affiliation(s)
- Li-Jie Zhou
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Chun-Ling Zhang
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Rui-Fen Zhang
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
- Qingdao Academy of Agricultural Science, Qing-Dao, Shandong 266100, China
| | - Gui-Luan Wang
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Yuan-Yuan Li
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Yu-Jin Hao
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| |
Collapse
|
25
|
Zhou LJ, Zhang CL, Zhang RF, Wang GL, Li YY, Hao YJ. The SUMO E3 Ligase MdSIZ1 Targets MdbHLH104 to Regulate Plasma Membrane H +-ATPase Activity and Iron Homeostasis. PLANT PHYSIOLOGY 2019; 179:88-106. [PMID: 30333149 PMCID: PMC6324222 DOI: 10.1104/pp.18.00289] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 10/09/2018] [Indexed: 05/20/2023]
Abstract
SIZ1 (a SIZ/PIAS-type SUMO E3 ligase)-mediated small ubiquitin-like modifier (SUMO) modification of target proteins is important for various biological processes related to abiotic stress resistance in plants; however, little is known about its role in resistance toward iron (Fe) deficiency. Here, the SUMO E3 ligase MdSIZ1 was shown to be involved in the plasma membrane (PM) H+-ATPase-mediated response to Fe deficiency. Subsequently, a basic helix-loop-helix transcription factor, MdbHLH104 (a homolog of Arabidopsis bHLH104 in apple), which acts as a key component in regulating PM H+-ATPase-mediated rhizosphere acidification and Fe uptake in apples (Malus domestica), was identified as a direct target of MdSIZ1. MdSIZ1 directly sumoylated MdbHLH104 both in vitro and in vivo, especially under conditions of Fe deficiency, and this sumoylation was required for MdbHLH104 protein stability. Double substitution of K139R and K153R in MdbHLH104 blocked MdSIZ1-mediated sumoylation in vitro and in vivo, indicating that the K139 and K153 residues were the principal sites of SUMO conjugation. Moreover, the transcript level of the MdSIZ1 gene was substantially induced following Fe deficiency. MdSIZ1 overexpression exerted a positive influence on PM H+-ATPase-mediated rhizosphere acidification and Fe uptake. Our findings reveal an important role for sumoylation in the regulation of PM H+-ATPase-mediated rhizosphere acidification and Fe uptake during Fe deficiency in plants.
Collapse
Affiliation(s)
- Li-Jie Zhou
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Chun-Ling Zhang
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Rui-Fen Zhang
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
- Qingdao Academy of Agricultural Science, Qing-Dao, Shandong 266100, China
| | - Gui-Luan Wang
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Yuan-Yuan Li
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Yu-Jin Hao
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| |
Collapse
|
26
|
Khan SA, Li MZ, Wang SM, Yin HJ. Revisiting the Role of Plant Transcription Factors in the Battle against Abiotic Stress. Int J Mol Sci 2018; 19:ijms19061634. [PMID: 29857524 PMCID: PMC6032162 DOI: 10.3390/ijms19061634] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 05/10/2018] [Accepted: 05/24/2018] [Indexed: 01/01/2023] Open
Abstract
Owing to diverse abiotic stresses and global climate deterioration, the agricultural production worldwide is suffering serious losses. Breeding stress-resilient crops with higher quality and yield against multiple environmental stresses via application of transgenic technologies is currently the most promising approach. Deciphering molecular principles and mining stress-associate genes that govern plant responses against abiotic stresses is one of the prerequisites to develop stress-resistant crop varieties. As molecular switches in controlling stress-responsive genes expression, transcription factors (TFs) play crucial roles in regulating various abiotic stress responses. Hence, functional analysis of TFs and their interaction partners during abiotic stresses is crucial to perceive their role in diverse signaling cascades that many researchers have continued to undertake. Here, we review current developments in understanding TFs, with particular emphasis on their functions in orchestrating plant abiotic stress responses. Further, we discuss novel molecular mechanisms of their action under abiotic stress conditions. This will provide valuable information for understanding regulatory mechanisms to engineer stress-tolerant crops.
Collapse
Affiliation(s)
- Sardar-Ali Khan
- State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Meng-Zhan Li
- State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Suo-Min Wang
- State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Hong-Ju Yin
- State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China.
| |
Collapse
|
27
|
Zhao Q, Xiang X, Liu D, Yang A, Wang Y. Tobacco Transcription Factor NtbHLH123 Confers Tolerance to Cold Stress by Regulating the NtCBF Pathway and Reactive Oxygen Species Homeostasis. FRONTIERS IN PLANT SCIENCE 2018; 9:381. [PMID: 29643858 PMCID: PMC5882786 DOI: 10.3389/fpls.2018.00381] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 03/08/2018] [Indexed: 05/03/2023]
Abstract
Cold stress is a major environmental factor that impairs plant growth and development, geographic distribution, and crop productivity. The C-repeat binding factor (CBF) regulatory pathway has an essential role in response to cold stress. Here, we characterized a bHLH transcription factor from Nicotiana tabacum, NtbHLH123, in response to cold stress (4°C). Overexpression of NtbHLH123 enhanced cold tolerance in transgenic tobacco plants. Based on yeast one-hybrid, chromatin immunoprecipitation PCR, and transient expression analysis assays, NtbHLH123 binds directly to the G-box/E-box motifs in the promoter of the NtCBF genes and positively regulates their expression. Furthermore, NtbHLH123-overexpressing plants showed lower electrolyte leakage, reduced malondialdehyde contents, H2O2 and reactive oxygen species (ROS) accumulation under cold stress, which contributed to alleviating oxidative damage to the cell membrane after cold stress treatment. And NtbHLH123 increased stress tolerance by improving the expression of a number of abiotic stress-responsive genes to mediate the ROS scavenging ability and other stress tolerance pathways. Taken together, we present a model suggesting that NtbHLH123 is a transcriptional activator that functions as a positive regulator of cold tolerance by activating NtCBF, ROS scavenging-related, and stress-responsive genes.
Collapse
Affiliation(s)
- Qiang Zhao
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
- *Correspondence: Qiang Zhao, Yuanying Wang,
| | | | - Dan Liu
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Aiguo Yang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Yuanying Wang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
- *Correspondence: Qiang Zhao, Yuanying Wang,
| |
Collapse
|
28
|
Zhang H, Li Y, Yao X, Liang G, Yu D. POSITIVE REGULATOR OF IRON HOMEOSTASIS1, OsPRI1, Facilitates Iron Homeostasis. PLANT PHYSIOLOGY 2017; 175:543-554. [PMID: 28751317 PMCID: PMC5580773 DOI: 10.1104/pp.17.00794] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 07/25/2017] [Indexed: 05/19/2023]
Abstract
Oryza sativa HEMERYTHRIN MOTIF-CONTAINING REALLY INTERESTING NEW GENE AND ZINC-FINGER PROTEIN1 (OsHRZ1) is a putative iron-binding sensor. However, it is unclear how OsHRZ1 transmits signals. In this study, we reveal that POSITIVE REGULATOR OF IRON HOMEOSTASIS1 (OsPRI1) interacts with OsHRZ1. A loss-of-function mutation to OsPRI1 increased the sensitivity of plants to Fe-deficient conditions and down-regulated the expression of Fe-deficiency-responsive genes. Yeast one-hybrid and electrophoretic mobility shift assay results suggested that OsPRI1 binds to the OsIRO2 and OsIRO3 promoters. In vitro ubiquitination experiments indicated that OsPRI1 is ubiquitinated by OsHRZ1. Cell-free degradation assays revealed that the stability of OsPRI1 decreased in wild-type roots but increased in the hrz1-2 mutant, suggesting OsHRZ1 is responsible for the instability of OsPRI1. The hrz1-2 seedlings were insensitive to Fe-deficient conditions. When the pri1-1 mutation was introduced into hrz1-2 mutants, the pri1hrz1 double mutant was more sensitive to Fe deficiency than the hrz1-2 mutant. Additionally, the expression levels of Fe-deficiency-responsive genes were lower in the hrz1pri1 double mutant than in the hrz1-2 mutant. Collectively, these results imply that OsPRI1, which is ubiquitinated by OsHRZ1, mediates rice responses to Fe deficiency by positively regulating OsIRO2 and OsIRO3 expression as part of the OsHRZ1-OsPRI1-OsIRO2/3 signal transduction cascade.
Collapse
Affiliation(s)
- Huimin Zhang
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yang Li
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Xiani Yao
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gang Liang
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Diqiu Yu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| |
Collapse
|
29
|
dos Santos RS, de Araujo AT, Pegoraro C, de Oliveira AC. Dealing with iron metabolism in rice: from breeding for stress tolerance to biofortification. Genet Mol Biol 2017; 40:312-325. [PMID: 28304072 PMCID: PMC5452141 DOI: 10.1590/1678-4685-gmb-2016-0036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 09/22/2016] [Indexed: 12/23/2022] Open
Abstract
Iron is a well-known metal. Used by humankind since ancient times in many different ways, this element is present in all living organisms, where, unfortunately, it represents a two-way problem. Being an essential block in the composition of different proteins and metabolic pathways, iron is a vital component for animals and plants. That is why iron deficiency has a severe impact on the lives of different organisms, including humans, becoming a major concern, especially in developing countries where access to adequate nutrition is still difficult. On the other hand, this metal is also capable of causing damage when present in excess, becoming toxic to cells and affecting the whole organism. Because of its importance, iron absorption, transport and storage mechanisms have been extensively investigated in order to design alternatives that may solve this problem. As the understanding of the strategies that plants use to control iron homeostasis is an important step in the generation of improved plants that meet both human agricultural and nutritional needs, here we discuss some of the most important points about this topic.
Collapse
Affiliation(s)
- Railson Schreinert dos Santos
- Plant Genomics and Breeding Center (CGF), Universidade Federal de
Pelotas, Pelotas, RS, Brazil
- Technology Development Center (CDTec), Universidade Federal de
Pelotas, Pelotas, RS, Brazil
| | | | - Camila Pegoraro
- Plant Genomics and Breeding Center (CGF), Universidade Federal de
Pelotas, Pelotas, RS, Brazil
| | - Antonio Costa de Oliveira
- Plant Genomics and Breeding Center (CGF), Universidade Federal de
Pelotas, Pelotas, RS, Brazil
- Technology Development Center (CDTec), Universidade Federal de
Pelotas, Pelotas, RS, Brazil
| |
Collapse
|
30
|
Liang G, Zhang H, Li X, Ai Q, Yu D. bHLH transcription factor bHLH115 regulates iron homeostasis in Arabidopsis thaliana. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1743-1755. [PMID: 28369511 PMCID: PMC5441899 DOI: 10.1093/jxb/erx043] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Iron (Fe) deficiency is a limiting factor for the normal growth and development of plants, and many species have evolved sophisticated systems for adaptation to Fe-deficient environments. It is still unclear how plants sense Fe status and coordinate the expression of genes responsive to Fe deficiency. In this study, we show that the bHLH transcription factor bHLH115 is a positive regulator of the Fe-deficiency response. Loss-of-function of bHLH115 causes strong Fe-deficiency symptoms and alleviates expression of genes responsive to Fe deficiency, whereas its overexpression causes the opposite effect. Chromatin immunoprecipitation assays confirmed that bHLH115 binds to the promoters of the Fe-deficiency-responsive genes bHLH38/39/100/101 and POPEYE (PYE), which suggests redundant molecular functions with bHLH34, bHLH104, and bHLH105. This is further supported by the fact that the bhlh115-1 mutant was complemented by overexpression of any of bHLH34, bHLH104, bHLH105, and bHLH115. Further investigations determined that bHLH115 could interact with itself and with bHLH34, bHLH104, and bHLH105. Their differential tissue-specific expression patterns and the severe Fe deficiency symptoms of multiple mutants supported their non-redundant biological functions. Genetic analysis revealed that bHLH115 is negatively regulated by BRUTUS (BTS), an E3 ligase that can interact with bHLH115. Thus, bHLH115 plays key roles in the maintenance of Fe homeostasis in Arabidopsis thaliana.
Collapse
Affiliation(s)
- Gang Liang
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences Kunming, Yunnan 650223, China
| | - Huimin Zhang
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences Kunming, Yunnan 650223, China
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Xiaoli Li
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences Kunming, Yunnan 650223, China
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Qin Ai
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences Kunming, Yunnan 650223, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Diqiu Yu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences Kunming, Yunnan 650223, China
| |
Collapse
|
31
|
Zhao Q, Ren YR, Wang QJ, Wang XF, You CX, Hao YJ. Ubiquitination-Related MdBT Scaffold Proteins Target a bHLH Transcription Factor for Iron Homeostasis. PLANT PHYSIOLOGY 2016; 172:1973-1988. [PMID: 27660166 PMCID: PMC5100752 DOI: 10.1104/pp.16.01323] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 09/14/2016] [Indexed: 05/20/2023]
Abstract
Iron (Fe) homeostasis is crucial for plant growth and development. A network of basic helix-loop-helix (bHLH) transcription factors positively regulates Fe uptake during iron deficiency. However, their up-regulation or overexpression leads to Fe overload and reactive oxygen species generation, thereby damaging the plants. Here, we found that two BTB/TAZ proteins, MdBT1 and MdBT2, interact with the MbHLH104 protein in apple. In addition, the function of MdBT2 was characterized as a regulator of MdbHLH104 degradation via ubiquitination and the 26S proteasome pathway, thereby controlling the activity of plasma membrane H+-ATPases and the acquisition of iron. Furthermore, MdBT2 interacted with MdCUL3 proteins, which were required for the MdBT2-mediated ubiquitination modification of MdbHLH104 and its degradation. In sum, our findings demonstrate that MdBT proteins interact with MdCUL3 to bridge the formation of the MdBTsMdCUL3 complex, which negatively modulates the degradation of the MdbHLH104 protein in response to changes in Fe status to maintain iron homeostasis in plants.
Collapse
Affiliation(s)
- Qiang Zhao
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, and College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Yi-Ran Ren
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, and College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Qing-Jie Wang
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, and College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Xiao-Fei Wang
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, and College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Chun-Xiang You
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, and College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| | - Yu-Jin Hao
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, and College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China
| |
Collapse
|
32
|
Zhao Q, Ren YR, Wang QJ, Yao YX, You CX, Hao YJ. Overexpression of MdbHLH104 gene enhances the tolerance to iron deficiency in apple. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:1633-45. [PMID: 26801352 PMCID: PMC5066684 DOI: 10.1111/pbi.12526] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Revised: 11/14/2015] [Accepted: 12/07/2015] [Indexed: 05/17/2023]
Abstract
Fe deficiency is a widespread nutritional disorder in plants. The basic helix-loop-helix (bHLH) transcription factors (TFs), especially Ib subgroup bHLH TFs which are involved in iron uptake, have been identified. In this study, an IVc subgroup bHLH TF MdbHLH104 was identified and characterized as a key component in the response to Fe deficiency in apple. The overexpression of the MdbHLH104 gene noticeably increased the H(+) -ATPase activity under iron limitation conditions and the tolerance to Fe deficiency in transgenic apple plants and calli. Further investigation showed that MdbHLH104 proteins bonded directly to the promoter of the MdAHA8 gene, thereby positively regulating its expression, the plasma membrane (PM) H(+) -ATPase activity and Fe uptake. Similarly, MdbHLH104 directly modulated the expression of three Fe-responsive bHLH genes, MdbHLH38, MdbHLH39 and MdPYE. In addition, MdbHLH104 interacted with 5 other IVc subgroup bHLH proteins to coregulate the expression of the MdAHA8 gene, the activity of PM H(+) -ATPase and the content of Fe in apple calli. Therefore, MdbHLH104 acts together with other apple bHLH TFs to regulate Fe uptake by modulating the expression of the MdAHA8 gene and the activity of PM H(+) -ATPase in apple.
Collapse
Affiliation(s)
- Qiang Zhao
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong, China
| | - Yi-Ran Ren
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong, China
| | - Qing-Jie Wang
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong, China
| | - Yu-Xin Yao
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong, China
| | - Chun-Xiang You
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong, China
| | - Yu-Jin Hao
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong, China
| |
Collapse
|
33
|
Shen C, Yang Y, Liu K, Zhang L, Guo H, Sun T, Wang H. Involvement of endogenous salicylic acid in iron-deficiency responses in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:4179-93. [PMID: 27208542 DOI: 10.1093/jxb/erw196] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Several phytohormones have been demonstrated to be involved in iron (Fe) homeostasis. We took advantage of a salicylic acid (SA) biosynthesis defective mutant phytoalexin deficient 4 (pad4: T-DNA Salk_089936) to explore the possible effects of endogenous SA on the morphological and physiological responses to Fe deprivation. The morphological and physiological analysis was carried out between Col-0 and the pad4 mutant. Under an Fe-deficiency treatment, Col-0 showed more severe leaf chlorosis and root growth inhibition compared with the pad4 mutant. The soluble Fe concentrations were significantly higher in pad4 than in Col-0 under the Fe-deficiency treatment. Fe deficiency significantly induced SA accumulation in Col-0 and the loss-of-function of PAD4 blocked this process. The requirement of endogenous SA accumulation for Fe-deficiency responses was confirmed using a series of SA biosynthetic mutants and transgenic lines. Furthermore, a comparative RNA sequencing analysis of the whole seedling transcriptomes between Col-0 and the pad4 mutant was also performed. Based on the transcriptome data, the expression levels of many auxin- and ethylene-response genes were altered in pad4 compared with Col-0. Fe deficiency increases SA contents which elevates auxin and ethylene signalling, thereby activating Fe translocation via the bHLH38/39-mediated transcriptional regulation of downstream Fe genes.
Collapse
Affiliation(s)
- Chenjia Shen
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China
| | - Yanjun Yang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China
| | - Kaidong Liu
- Life Science and Technology School, Lingnan Normal University, Zhanjiang, Guangdong 524048, China
| | - Lei Zhang
- Department of Plant Pathology, North Carolina State University, Raleigh, NC 27607, USA
| | - Hong Guo
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China
| | - Tao Sun
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China
| | - Huizhong Wang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China
| |
Collapse
|
34
|
Involvement of CmWRKY10 in Drought Tolerance of Chrysanthemum through the ABA-Signaling Pathway. Int J Mol Sci 2016; 17:ijms17050693. [PMID: 27187353 PMCID: PMC4881519 DOI: 10.3390/ijms17050693] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 04/15/2016] [Accepted: 04/28/2016] [Indexed: 12/30/2022] Open
Abstract
Drought is one of the important abiotic factors that adversely affects plant growth and production. The WRKY transcription factor plays a pivotal role in plant growth and development, as well as in the elevation of many abiotic stresses. Among three major groups of the WRKY family, the group IIe WRKY has been the least studied in floral crops. Here, we report functional aspects of group IIe WRKY member, i.e., CmWRKY10 in chrysanthemum involved in drought tolerance. The transactivation assay showed that CmWRKY10 had transcriptional activity in yeast cells and subcellular localization demonstrated that it was localized in nucleus. Our previous study showed that CmWRKY10 could be induced by drought in chrysanthemum. Moreover, the overexpression of CmWRKY10 in transgenic chrysanthemum plants improved tolerance to drought stress compared to wild-type (WT). High expression of DREB1A, DREB2A, CuZnSOD, NCED3A, and NCED3B transcripts in overexpressed plants provided strong evidence that drought tolerance mechanism was associated with abscisic acid (ABA) pathway. In addition, lower accumulation of reactive oxygen species (ROS) and higher enzymatic activity of peroxidase, superoxide dismutase and catalase in CmWRKY10 overexpressed lines than that of WT demonstrates its role in drought tolerance. Together, these findings reveal that CmWRKY10 works as a positive regulator in drought stress by regulating stress-related genes.
Collapse
|
35
|
A Novel bHLH Transcription Factor Involved in Regulating Anthocyanin Biosynthesis in Chrysanthemums (Chrysanthemum morifolium Ramat.). PLoS One 2015; 10:e0143892. [PMID: 26619181 PMCID: PMC4664390 DOI: 10.1371/journal.pone.0143892] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/10/2015] [Indexed: 12/21/2022] Open
Abstract
Chrysanthemums (Chrysanthemum morifolium Ramat.) exhibit a variety of flower colors due to their differing abilities to accumulate anthocyanins. One MYB member, CmMYB6, has been verified as a transcription regulator of chrysanthemum genes involved in anthocyanin biosynthesis; however, the co-regulators for CmMYB6 remain unclear in chrysanthemum. Here, the expression pattern of CmbHLH2, which is clustered in the IIIf bHLH subgroup, was shown to be positively correlated with the anthocyanin content of cultivars with red, pink and yellow flower colors, respectively. CmbHLH2 significantly upregulated the CmDFR promoter and triggered anthocyanin accumulation when co-expressed with CmMYB6. Yeast one-hybrid analyses indicated that CmbHLH2 was able to bind directly to the CmDFR promoter. Moreover, yeast two-hybrid assays indicated protein-protein interaction between CmbHLH2 and CmMYB6. These results suggest that CmbHLH2 is the essential partner for CmMYB6 in regulating anthocyanin biosynthesis in chrysanthemum.
Collapse
|
36
|
Zhang J, Liu B, Li M, Feng D, Jin H, Wang P, Liu J, Xiong F, Wang J, Wang HB. The bHLH transcription factor bHLH104 interacts with IAA-LEUCINE RESISTANT3 and modulates iron homeostasis in Arabidopsis. THE PLANT CELL 2015; 27:787-805. [PMID: 25794933 PMCID: PMC4558652 DOI: 10.1105/tpc.114.132704] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 02/02/2015] [Accepted: 02/17/2015] [Indexed: 05/18/2023]
Abstract
Iron (Fe) is an indispensable micronutrient for plant growth and development. The regulation of Fe homeostasis in plants is complex and involves a number of transcription factors. Here, we demonstrate that a basic helix-loop-helix (bHLH) transcription factor, bHLH104, belonging to the IVc subgroup of bHLH family, acts as a key component positively regulating Fe deficiency responses. Knockout of bHLH104 in Arabidopsis thaliana greatly reduced tolerance to Fe deficiency, whereas overexpression of bHLH104 had the opposite effect and led to accumulation of excess Fe in soil-grown conditions. The activation of Fe deficiency-inducible genes was substantially suppressed by loss of bHLH104. Further investigation showed that bHLH104 interacted with another IVc subgroup bHLH protein, IAA-LEUCINE RESISTANT3 (ILR3), which also plays an important role in Fe homeostasis. Moreover, bHLH104 and ILR3 could bind directly to the promoters of Ib subgroup bHLH genes and POPEYE (PYE) functioning in the regulation of Fe deficiency responses. Interestingly, genetic analysis showed that loss of bHLH104 could decrease the tolerance to Fe deficiency conferred by the lesion of BRUTUS, which encodes an E3 ligase and interacts with bHLH104. Collectively, our data support that bHLH104 and ILR3 play pivotal roles in the regulation of Fe deficiency responses via targeting Ib subgroup bHLH genes and PYE expression.
Collapse
Affiliation(s)
- Jie Zhang
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Bing Liu
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Mengshu Li
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Dongru Feng
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Honglei Jin
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Peng Wang
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Jun Liu
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Feng Xiong
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Jinfa Wang
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| | - Hong-Bin Wang
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275 Guangzhou, People's Republic of China
| |
Collapse
|