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Li C, Feng Y, Tian P, Yu X. Mathematical Estimation of Endogenous Proline as a Bioindicator to Regulate the Stress of Trivalent Chromium on Rice Plants Grown in Different Nitrogenous Conditions. TOXICS 2023; 11:803. [PMID: 37888654 PMCID: PMC10611392 DOI: 10.3390/toxics11100803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/14/2023] [Accepted: 09/20/2023] [Indexed: 10/28/2023]
Abstract
The accumulation of proline impacts the defense mechanisms of plants against the harmful effects of adverse environmental conditions; however, its concentration in plants is associated with the metabolism of N. Therefore, the effects of exogenous organic [glutamate (Glu)/arginine (Arg)] and inorganic [nitrate (NO3-)/ammonium (NH4+)] N on the accumulation of proline (Pro) in rice plants under trivalent chromium [Cr(III)] stress were studied through using the mass balance matrix model (MBMM). Application of 'NH4+' showed the largest contribution to the Pro content in rice shoots under different concentrations of Cr(III), followed by 'NO3-', 'Arg', and 'Glu' applications. On the other hand, 'Arg' application displayed the largest contribution to the Pro content in roots under Cr(III) stress, followed by 'NH4+', 'Glu', and 'NO3-' applications. The combined application of 'NH4++Arg' showed the greatest contribution to the Pro content in both roots and shoots of Cr(III)-treated rice seedlings, while the application of 'NO3-+Glu' showed the least contribution to the Pro content in rice seedlings. The current study indicated that the endogenous level of Pro in rice seedlings is quite sensitive to Cr(III) stress under different N sources, and the mathematical modeling showed a reliable result while estimating the relationship between Pro content and N source application.
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Affiliation(s)
| | | | | | - Xiaozhang Yu
- College of Environmental Science & Engineering, Guilin University of Technology, Guilin 541004, China (Y.F.)
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Liu L, Cui K, Qi X, Wu Y, Huang J, Peng S. Varietal responses of root characteristics to low nitrogen application explain the differing nitrogen uptake and grain yield in two rice varieties. FRONTIERS IN PLANT SCIENCE 2023; 14:1244281. [PMID: 37600168 PMCID: PMC10435752 DOI: 10.3389/fpls.2023.1244281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 07/18/2023] [Indexed: 08/22/2023]
Abstract
Rice root characteristics are tightly associated with high-efficient nitrogen uptake. To understand the relationship of root plastic responses with nitrogen uptake when reducing nitrogen application for green rice production, a hydroponic experiment and a soil pot experiment were conducted under high (HN) and low (LN) nitrogen applications, using two rice (Oryza sativa L.) varieties, NK57 and YD6, three nitrogen absorption traits (total nitrogen accumulation, net NH4 + influx on root surface, nitrogen uptake via apoplasmic pathway) and root characteristics were investigated. In comparison with HN, LN significantly reduced nitrogen absorption and grain yield in both varieties. Concomitantly, there was a decrease in total root length, root surface area, root number, root volume, and root cortical area under LN, while single root length, root aerenchyma area, and root lignin content increased. The expression of OsAMT1;1 and OsAMT1;2 down-regulated in both varieties. The findings revealed that YD6 had smaller reduction degree for the three nitrogen absorption traits and grain yield, accompanied by smaller reduction degree in total root length, root surface area, root cortical area, and expression of the two genes under LN. These root characteristics were significantly and positively correlated with the three nitrogen absorption traits and grain yield, especially under LN. These results indicate that a large root system, lower reduction degree in several root characters, and high expression of OsAMT genes in YD6 explains its high nitrogen accumulation and grain yield under reduced nitrogen application. The study may provide rationale for developing varieties with low nitrogen fertilizer requirements for enabling green rice production.
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Affiliation(s)
- Lei Liu
- National Key Laboratory of Crop Genetic Improvement, Wuhan, Hubei, China
- Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, Hubei, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Kehui Cui
- National Key Laboratory of Crop Genetic Improvement, Wuhan, Hubei, China
- Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, Hubei, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Xiaoli Qi
- National Key Laboratory of Crop Genetic Improvement, Wuhan, Hubei, China
- Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, Hubei, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yu Wu
- National Key Laboratory of Crop Genetic Improvement, Wuhan, Hubei, China
- Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, Hubei, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jianliang Huang
- National Key Laboratory of Crop Genetic Improvement, Wuhan, Hubei, China
- Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, Hubei, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Shaobing Peng
- National Key Laboratory of Crop Genetic Improvement, Wuhan, Hubei, China
- Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, Hubei, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
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Fu YF, Yang XY, Zhang ZW, Yuan S. Synergistic effects of nitrogen metabolites on auxin regulating plant growth and development. FRONTIERS IN PLANT SCIENCE 2022; 13:1098787. [PMID: 36605959 PMCID: PMC9807920 DOI: 10.3389/fpls.2022.1098787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Nitrogen is one of the important nutrients required for plant growth and development. There is increasing evidences that almost all types of nitrogen metabolites affect, at least to some extent, auxin content and/or signaling in plants, which in turn affects seed germination, plant root elongation, gravitropism, leaf expansion and floral transition. This opinion focuses on the roles of nitrogen metabolites, NO 3 - , NH 4 + , tryptophan and NO and their synergistic effects with auxin on plant growth and development. Nitrate reductase (NR) converts nitrate into nitrite, and was roughly positive-correlated with the root auxin level, suggesting a crosstalk between nitrate signaling and auxin signaling. Abscisic Acid Responsive Element Binding Factor 3 (AFB3) and Tryptophan Aminotransferase of Arabidopsis 1 (TAA1) are also the key enzymes involved in nitrogen metabolite-regulated auxin biosynthesis. Recent advances in the crosstalk among NO 3 - , NH 4 + , tryptophan and NO in regulation to NR, AFB3 and TAA1 are also summarized.
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Affiliation(s)
- Yu-Fan Fu
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Xin-Yue Yang
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Zhong-Wei Zhang
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Shu Yuan
- College of Resources, Sichuan Agricultural University, Chengdu, China
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Rajendran S, Kim CM. OsCSLD1 Mediates NH 4+-Dependent Root Hair Growth Suppression and AMT1;2 Expression in Rice ( Oryza sativa L.). PLANTS (BASEL, SWITZERLAND) 2022; 11:3580. [PMID: 36559692 PMCID: PMC9788582 DOI: 10.3390/plants11243580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 12/07/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
Root hairs play crucial roles in the roots, including nutrient uptake, water assimilation, and anchorage with soil, along with supporting rhizospheric microorganisms. In rice, ammonia uptake is mediated by a specialized ammonium transporter (AMT). AMT1;1, AMT1;2, and AMT1;3 have been extensively studied in relation to nitrogen signaling. Cellulose synthase-like D1 (CSLD1) is essential for cell expansion and is highly specific to root hair cells. csld1 mutants showed successful initiation but failed to elongate. However, when nitrogen was depleted, csld1 root hairs resumed elongation. Further experiments revealed that in the presence of ammonium (NH4+), csld1 roots failed to elongate. csld1 elongated normally in the presence of nitrate (NO3−). Expression analysis showed an increase in root hair-specific AMT1;2 expression in csld1. CSLD1 was positively co-expressed with AMT1;2 changing nitrogen concentration in the growth media. CSLD1 showed increased expression in the presence of both ammonium and nitrate. Methylammonium (MeA) treatment of CSLD1 overexpression lines suggests that CSLD1 does not directly participate in nitrogen transport. Further studies on the root hair elongation mutant sndp1 showed that nitrogen assimilation is unlikely to depend on root hair length. Therefore, these results suggest that CSLD1 is closely involved in nitrogen-dependent root hair elongation and regulation of AMT1;2 expression in rice roots.
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Genome-Wide Identification of AMT2-Type Ammonium Transporters Reveal That CsAMT2.2 and CsAMT2.3 Potentially Regulate NH 4+ Absorption among Three Different Cultivars of Camellia sinensis. Int J Mol Sci 2022; 23:ijms232415661. [PMID: 36555302 PMCID: PMC9779401 DOI: 10.3390/ijms232415661] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/30/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022] Open
Abstract
Ammonium (NH4+), as a major inorganic source of nitrogen (N) for tea plant growth, is transported and distributed across membranes by the proteins of ammonium transporters (AMTs). However, the AMT2-type AMTs from tea plants remain poorly understood. In this study, five CsAMT2 subfamily genes were identified in tea plant genomes, and their full-length coding sequences (CDS) were isolated from roots. Then, a NH4+ uptake kinetic comparison of Fudingdabaicha (FD), Huangdan (HD), and Maoxie (MX) showed that FD was a high N efficiency (HNE) cultivar that had a wide range of adaptability to NH4+, HD was a high N efficiency under high N conditions (HNEH) cultivar, in which it was easy to obtain higher yield in a high N environment, and MX was a high N efficiency under low N conditions (HNEL) cultivar, which had a higher affinity for NH4+ than the other two. Tissue-specific expression analysis suggested that CsAMT2.2 and CsAMT2.3 were highly expressed in the roots, indicating that these two members may be unique in the CsAMT2 subfamily. This is further supported by our findings from the temporal expression profiles in the roots among these three different N adaptation cultivars. Expression levels of CsAMT2.2 and CsAMT2.3 in FD and HD were upregulated by a short time (2 h) under high NH4+ treatment, while under low NH4+ treatment, CsAMT2.2 and CsAMT2.3 were highly expressed at 0 h and 2 h in the HNEL-type cultivar-MX. Furthermore, the functional analysis illustrated that CsAMT2.2 and CsAMT2.3 could make a functional complementation of NH4+-defective mutant yeast cells at low NH4+ levels, and the transport efficiency of CsAMT2.3 was higher than that of CsAMT2.2. Thus, we concluded that CsAMT2.2 and CsAMT2.3 might play roles in controlling the NH4+ uptake from the soil to the roots. These results will further the understanding of the NH4+ signal networks of AMT2-type proteins in tea plants.
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Wang Y, Xuan YM, Wang SM, Fan DM, Wang XC, Zheng XQ. Genome-wide identification, characterization, and expression analysis of the ammonium transporter gene family in tea plants (Camellia sinensis L.). PHYSIOLOGIA PLANTARUM 2022; 174:e13646. [PMID: 35129836 DOI: 10.1111/ppl.13646] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 01/30/2022] [Accepted: 02/02/2022] [Indexed: 06/14/2023]
Abstract
As a preferred nitrogen form, ammonium (NH4 + ) transport via specific transporters is particularly important for the growth and development of tea plants (Camellia sinensis L.). However, our understanding of the functions of the AMT family in tea plants is limited. We identified and named 16 putative AMT genes according to phylogenetic analysis. All CsAMT genes were divided into three groups, distributed on 12 chromosomes with only one segmental duplication repetition. The CsAMT genes showed different expression levels in different organs, and most of them were expressed mainly in the apical buds and roots. Complementation analysis of yeast mutants showed that CsAMTs restored the uptake of NH4 + . This study provides insights into the genome-wide distribution and spatial expression of AMT genes in tea plants.
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Affiliation(s)
- Yu Wang
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Yi-Min Xuan
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Shu-Mao Wang
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Dong-Mei Fan
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Xiao-Chang Wang
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Xin-Qiang Zheng
- Tea Research Institute, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
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Hao DL, Zhou JY, Yang SY, Huang YN, Su YH. Functional and Regulatory Characterization of Three AMTs in Maize Roots. FRONTIERS IN PLANT SCIENCE 2020; 11:884. [PMID: 32676086 PMCID: PMC7333355 DOI: 10.3389/fpls.2020.00884] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
Maize grows in nitrate-dominated dryland soils, but shortly upon localized dressing of nitrogen fertilizers, ammonium is retained as a noticeable form of nitrogen source available to roots. Thus in addition to nitrate, the absorption of ammonium can be an important strategy that promotes rapid plant growth at strong nitrogen demanding stages. The present study reports the functional characterization of three root-expressed ammonium transporters (AMTs), aiming at finding out functional and regulatory properties that correlate with efficient nitrogen acquisition of maize. Using a stable electrophysiological recording method we previously established in Xenopus laevis oocytes that integrates the capture of currents in response to voltage ramps with onsite stability controls, we demonstrate that all three ZmAMT1s engage NH4 + uniporting as ammonium uptake mechanisms. The K m value for ZmAMT1.1a, 1.1b, or ZmAMT1.3 is, respectively, 9.9, 15.6, or 18.6 μM, indicating a typical high-affinity transport of NH4 + ions. Importantly, the uptake currents of these ZmAMT1s are markedly amplified upon extracellular acidification. A pH drop from 7.4 to 5.4 results in a 140.8%, 64.1% or a 120.7% increase of ammonium uptake activity through ZmAMT1.1a, 1.1b, or ZmAMT1.3. Since ammonium uptake by plant roots accompanies a spontaneous acidification to the root medium, the functional promotion of ZmAMT1.1a, 1.1b, and ZmAMT1.3 by low pH is in line with the facilitated ammonium uptake activity in maize roots. Furthermore, the expression of the three ZmAMT1 genes is induced under ammonium-dominated conditions. Thus we describe a facilitated ammonium uptake strategy in maize roots by functional and expression regulations of ZmAMT1 transporters that may coordinate with efficient acquisition of this form of nitrogen source when available.
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Sun YC, Sheng S, Fan TF, Liu L, Ke J, Wang DB, Hua JP, Liu LH, Cao FQ. Molecular identification and functional characterization of GhAMT1.3 in ammonium transport with a high affinity from cotton (Gossypium hirsutum L.). PHYSIOLOGIA PLANTARUM 2019; 167:217-231. [PMID: 30467856 DOI: 10.1111/ppl.12882] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/10/2018] [Accepted: 11/19/2018] [Indexed: 06/09/2023]
Abstract
Ammonium (NH4 + ) represents a primary nitrogen source for many plants, its effective transport into and between tissues and further assimilation in cells determine greatly plant nitrogen use efficiency. However, biological components involved in NH4 + movement in woody plants are unclear. Here, we report kinetic evidence for cotton NH4 + uptake and molecular identification of certain NH4 + transporters (AMTs) from cotton (Gossypium hirustum). A substrate-influx assay using 15 N-isotope revealed that cotton possessed a high-affinity transport system with a Km of 58 μM for NH4 + . Sequence analysis showed that GhAMT1.1-1.3 encoded respectively a membrane protein containing 485, 509 or 499 amino acids. Heterologous functionality test demonstrated that GhAMT1.1-1.3 expression mediated NH4 + permeation across the plasma membrane (PM) of yeast and/or Arabidopsis qko-mutant cells, allowing a growth restoration of both mutants on NH4 + . Quantitative PCR measurement showed that GhAMT1.3 was expressed in roots and leaves and markedly up-regulated by N-starvation, repressed by NH4 + resupply and regulated diurnally and age-dependently, suggesting that GhAMT1.3 should be a N-responsive gene. Importantly, GhAMT1.3 expression in Arabidopsis improved plant growth on NH4 + and enhanced total nitrogen accumulation (∼50% more), conforming with the observation of 2-fold more NH4 + absorption by GhAMT1.3-transformed qko plant roots during a 1-h root influx period. Together with its targeting to the PM and saturated transport kinetics with a Km of 72 μM for NH4 + , GhAMT1.3 is suggested to be a high-affinity NH4 + permease that may play a significant role in cotton NH4 + acquisition and utilization, adding a new member in the plant AMT family.
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Affiliation(s)
- Yi-Chen Sun
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Song Sheng
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Teng-Fei Fan
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing, 400716, China
| | - Lu Liu
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Jie Ke
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Dai-Bin Wang
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing, 400716, China
| | - Jin-Ping Hua
- College of Agronomy and Biotechnology, Beijing Key Lab of Crop Genetic Improvement, China Agricultural University, Beijing, 100193, China
| | - Lai-Hua Liu
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, 100193, China
| | - Feng-Qiu Cao
- Shanghai Center for Plant Stress Biology, Institute of Plant Physiology Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
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Dechorgnat J, Francis KL, Dhugga KS, Rafalski JA, Tyerman SD, Kaiser BN. Tissue and nitrogen-linked expression profiles of ammonium and nitrate transporters in maize. BMC PLANT BIOLOGY 2019; 19:206. [PMID: 31109290 PMCID: PMC6528335 DOI: 10.1186/s12870-019-1768-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 04/09/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND In order to grow, plants rely on soil nutrients which can vary both spatially and temporally depending on the environment, the soil type or the microbial activity. An essential nutrient is nitrogen, which is mainly accessible as nitrate and ammonium. Many studies have investigated transport genes for these ions in Arabidopsis thaliana and recently in crop species, including Maize, Rice and Barley. However, in most crop species, an understanding of the participants in nitrate and ammonium transport across the soil plant continuum remains undefined. RESULTS We have mapped a non-exhaustive set of putative nitrate and ammonium transporters in maize. The selected transporters were defined based on previous studies comparing nitrate transport pathways conserved between Arabidopsis and Zea mays (Plett D et. al, PLOS ONE 5:e15289, 2010). We also selected genes from published studies (Gu R et. al, Plant and Cell Physiology, 54:1515-1524, 2013, Garnett T et. al, New Phytol 198:82-94, 2013, Garnett T et. al, Frontiers in Plant Sci 6, 2015, Dechorgnat J et. al, Front Plant Sci 9:531, 2018). To analyse these genes, the plants were grown in a semi-hydroponic system to carefully control nitrogen delivery and then harvested at both vegetative and reproductive stages. The expression patterns of 26 putative nitrogen transporters were then tested. Six putative genes were found not expressed in our conditions. Transcripts of 20 other genes were detected at both the vegetative and reproductive stages of maize development. We observed the expression of nitrogen transporters in all organs tested: roots, young leaves, old leaves, silks, cobs, tassels and husk leaves. We also followed the gene expression response to nitrogen starvation and resupply and uncovered mainly three expression patterns: (i) genes unresponsiveness to nitrogen supply; (ii) genes showing an increase of expression after nitrogen starvation; (iii) genes showing a decrease of expression after nitrogen starvation. CONCLUSIONS These data allowed the mapping of putative nitrogen transporters in maize at both the vegetative and reproductive stages of development. No growth-dependent expression was seen in our conditions. We found that nitrogen transporter genes were expressed in all the organs tested and in many cases were regulated by the availability of nitrogen supplied to the plant. The gene expression patterns in relation to organ specificity and nitrogen availability denote a speciality of nitrate and ammonium transporter genes and their probable function depending on the plant organ and the environment.
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Affiliation(s)
- Julie Dechorgnat
- University of Adelaide, School of Agriculture Food and Wine, 2B Hartley Grove, Urrbrae, SA 5064 Australia
- University of Sydney, School of Life and Environmental Sciences, 380 Werombi Road, Brownlow Hill, NSW 2570 Australia
| | - Karen L. Francis
- University of Adelaide, School of Agriculture Food and Wine, 2B Hartley Grove, Urrbrae, SA 5064 Australia
| | - Kanwarpal S. Dhugga
- Genetic Discovery Group, DuPont Pioneer, Johnston, IA 50131-1004 USA
- Present Address: Genetic Resources Group, International Center for Maize and Wheat Improvement (CIMMYT), El Batan, 56237 Texcoco, Mexico
| | - J. Antony Rafalski
- Genetic Discovery Group, DuPont Crop Genetics Research, DuPont Experimental Station, Building E353, Wilmington, DE 198803 USA
| | - Stephen D. Tyerman
- University of Adelaide, School of Agriculture Food and Wine, 2B Hartley Grove, Urrbrae, SA 5064 Australia
| | - Brent N. Kaiser
- University of Sydney, School of Life and Environmental Sciences, 380 Werombi Road, Brownlow Hill, NSW 2570 Australia
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Fan TF, Cheng XY, Shi DX, He MJ, Yang C, Liu L, Li CJ, Sun YC, Chen YY, Xu C, Zhang L, Liu LH. Molecular identification of tobacco NtAMT1.3 that mediated ammonium root-influx with high affinity and improved plant growth on ammonium when overexpressed in Arabidopsis and tobacco. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 264:102-111. [PMID: 28969790 DOI: 10.1016/j.plantsci.2017.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 06/07/2023]
Abstract
Although biological functions of ammonium (NH4+) transporters (AMTs) have been intensively studied in many plant species, little is known about molecular bases responsible for NH4+ movement in tobacco. Here, we reported the identification and functional characterization of a putative NH4+ transporter NtAMT1.3 from tobacco (Nicotiana tabacum). Analysis in silico showed that NtAMT1.3 encoded an integral membrane protein containing 464 amino acid residues and exhibiting 10 predicted transmembrane α-helices. Heterologous functionality study demonstrated that NtAMT1.3 expression facilitated NH4+ entry across plasma membrane of NH4+-uptake defective yeast and Arabidopsis qko mutant, allowing a restored growth of both yeast and Arabidopsis mutant on low NH4+. qPCR assay revealed that NtAMT1.3 was expressed in both roots and leaves and significantly up-regulated by nitrogen starvation and resupply of its putative substrate NH4+ and even nitrate, suggesting that NtAMT1.3 should represent a nitrogen-responsive gene. Critically, constitutive overexpression of NtAMT1.3 in tobacco per se improved obviously the growth of transgenic plants on NH4+ and enhanced leaf nitrogen (15% more) accumulation, consistent with observation of 35% more NH4+ uptake by the roots of transgenic lines in 20min root-influx test. Together with data showing its plasma membrane localization and saturated transport nature with Km of about 50μM for NH4+, we suggest that NtAMT1.3 acts an active NH4+ transporter that plays a significant role in NH4+ acquisition and utilization in tobacco.
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Affiliation(s)
- Teng-Fei Fan
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Xiao-Yuan Cheng
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Dong-Xue Shi
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Ming-Jie He
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; College of Agriculture Sciences, Hunan Agricultural University, Changsha 410128, China
| | - Chao Yang
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Lu Liu
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Chang-Jun Li
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Yi-Chen Sun
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Yi-Yin Chen
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Chen Xu
- Institute of Tobacco Science Research of Chongqing Tobacco Company, China Tobacco Corporation, Chongqing 400716, China
| | - Lei Zhang
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Lai-Hua Liu
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
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Gupta SM, Arora S, Mirza N, Pande A, Lata C, Puranik S, Kumar J, Kumar A. Finger Millet: A "Certain" Crop for an "Uncertain" Future and a Solution to Food Insecurity and Hidden Hunger under Stressful Environments. FRONTIERS IN PLANT SCIENCE 2017; 8:643. [PMID: 28487720 PMCID: PMC5404511 DOI: 10.3389/fpls.2017.00643] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 04/10/2017] [Indexed: 05/05/2023]
Abstract
Crop growth and productivity has largely been vulnerable to various abiotic and biotic stresses that are only set to be compounded due to global climate change. Therefore developing improved varieties and designing newer approaches for crop improvement against stress tolerance have become a priority now-a-days. However, most of the crop improvement strategies are directed toward staple cereals such as rice, wheat, maize etc., whereas attention on minor cereals such as finger millet [Eleusine coracana (L.) Gaertn.] lags far behind. It is an important staple in several semi-arid and tropical regions of the world with excellent nutraceutical properties as well as ensuring food security in these areas even during harsh environment. This review highlights the importance of finger millet as a model nutraceutical crop. Progress and prospects in genetic manipulation for the development of abiotic and biotic stress tolerant varieties is also discussed. Although limited studies have been conducted for genetic improvement of finger millets, its nutritional significance in providing minerals, calories and protein makes it an ideal model for nutrition-agriculture research. Therefore, improved genetic manipulation of finger millets for resistance to both abiotic and biotic stresses, as well as for enhancing nutrient content will be very effective in millet improvement. Key message: Apart from the excellent nutraceutical value of finger millet, its ability to tolerate various abiotic stresses and resist pathogens make it an excellent model for exploring vast genetic and genomic potential of this crop, which provide us a wide choice for developing strategies for making climate resilient staple crops.
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Affiliation(s)
- Sanjay Mohan Gupta
- Molecular Biology and Genetic Engineering Laboratory, Defence Institute of Bio-Energy Research, Defence Research and Development OrganisationHaldwani, India
| | - Sandeep Arora
- Department of Molecular Biology and Genetic Engineering, College of Basic Sciences and Humanities, G. B. Pant University of Agriculture and TechnologyPantnagar, India
| | - Neelofar Mirza
- Department of Molecular Biology and Genetic Engineering, College of Basic Sciences and Humanities, G. B. Pant University of Agriculture and TechnologyPantnagar, India
| | - Anjali Pande
- Department of Molecular Biology and Genetic Engineering, College of Basic Sciences and Humanities, G. B. Pant University of Agriculture and TechnologyPantnagar, India
| | - Charu Lata
- Council of Scientific and Industrial Research-National Botanical Research InstituteLucknow, India
| | - Swati Puranik
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, UK
| | - J. Kumar
- Department of Plant Pathology, College of Agriculture, G. B. Pant University of Agriculture and TechnologyPantnagar, India
| | - Anil Kumar
- Department of Molecular Biology and Genetic Engineering, College of Basic Sciences and Humanities, G. B. Pant University of Agriculture and TechnologyPantnagar, India
- *Correspondence: Anil Kumar,
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Hao D, Yang S, Huang Y, Su Y. Identification of structural elements involved in fine-tuning of the transport activity of the rice ammonium transporter OsAMT1;3. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 108:99-108. [PMID: 27423220 DOI: 10.1016/j.plaphy.2016.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/01/2016] [Accepted: 07/03/2016] [Indexed: 05/13/2023]
Abstract
Ammonium transporters (AMTs) are major routes for plant uptake of the NH4+-form nitrogen. Plant AMTs mediate predominantly the uptake of NH4+ and to a lesser extent, its organic analog methylammonium (MeA+). Mutagenesis studies on potential phosphorylation residues have achieved solid recognition that alteration of the phosphorylation status can result in allosteric regulation and impair the functionality of plant AMTs. However, molecular insights to the fine-tuning of a functional ammonium transporter remain less clear. In this report, we demonstrate that the rice root expressed OsAMT1;3 (Oryza sativa ammonium transporter 1;3) functions as a typical high-affinity NH4+ transporter and is weakly permeable to MeA+ using growth assays in NH4+ uptake defective yeast cells and electrophysiological measurements in Xenopus oocytes. Upon screening of six point mutations generated with the transporter, we identified two amino acid residues involved in the functional modulation of OsAMT1;3. The H199E mutation caused loss of transport activity whereas other five mutations retained the functionality of OsAMT1;3. Furthermore, the L56F mutation enabled respectively 5- and 3.5 -fold increased capability for NH4+ and MeA+ uptake with several-fold decreased affinity (Km) and accelerated Vmax values. Surprisingly, yeast cells expressing the L56F mutation shown increased Na+ toxicity leading to a speculation that enhanced Na+ permeation occurred with this mutation. The phenomenon was further supported by the observation of significant Na+ uptake current in oocytes. Our results seemingly support a speculation that the L56F mutation of OsAMT1;3 widens the substrate passage tunnel and allows enhanced permeability to NH4+ and larger ions MeA+ and Na+.
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Affiliation(s)
- Dongli Hao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shunying Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Yanan Huang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanhua Su
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
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Van Bockhaven J, Steppe K, Bauweraerts I, Kikuchi S, Asano T, Höfte M, De Vleesschauwer D. Primary metabolism plays a central role in moulding silicon-inducible brown spot resistance in rice. MOLECULAR PLANT PATHOLOGY 2015; 16:811-24. [PMID: 25583155 PMCID: PMC6638399 DOI: 10.1111/mpp.12236] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Over recent decades, a multitude of studies have shown the ability of silicon (Si) to protect various plants against a range of microbial pathogens exhibiting different lifestyles and infection strategies. Despite this relative wealth of knowledge, an understanding of the action mechanism of Si is still in its infancy, which hinders its widespread application for agricultural purposes. In an attempt to further elucidate the molecular underpinnings of Si-induced disease resistance, we studied the transcriptome of control and Si-treated rice plants infected with the necrotrophic brown spot fungus Cochliobolus miyabeanus. Analysis of brown spot-infected control plants suggested that C. miyabeanus represses plant photosynthetic processes and nitrate reduction in order to trigger premature senescence and cause disease. In Si-treated plants, however, these pathogen-induced metabolic alterations are strongly impaired, suggesting that Si alleviates stress imposed by the pathogen. Interestingly, Si also significantly increased photorespiration rates in brown spot-infected plants. Although photorespiration is often considered as a wasteful process, recent studies have indicated that this metabolic bypass also enhances resistance during abiotic stress and pathogen attack by protecting the plant's photosynthetic machinery. In view of these findings, our results favour a scenario in which Si enhances brown spot resistance by counteracting C. miyabeanus-induced senescence and cell death via increased photorespiration. Moreover, our results shed light onto the mechanistic basis of Si-induced disease control and support the view that, in addition to activating plant immune responses, Si can also reduce disease severity by interfering with pathogen virulence strategies.
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Affiliation(s)
- Jonas Van Bockhaven
- Laboratory of Phytopathology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
| | - Ingvar Bauweraerts
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
| | - Shoshi Kikuchi
- Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences, Tsukuba, 305-8602, Ibaraki, Japan
| | - Takayuki Asano
- Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences, Tsukuba, 305-8602, Ibaraki, Japan
| | - Monica Höfte
- Laboratory of Phytopathology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
| | - David De Vleesschauwer
- Laboratory of Phytopathology, Faculty of Bioscience Engineering, Ghent University, B-9000, Ghent, Belgium
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14
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Bao A, Liang Z, Zhao Z, Cai H. Overexpressing of OsAMT1-3, a High Affinity Ammonium Transporter Gene, Modifies Rice Growth and Carbon-Nitrogen Metabolic Status. Int J Mol Sci 2015; 16:9037-63. [PMID: 25915023 PMCID: PMC4463577 DOI: 10.3390/ijms16059037] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 04/11/2015] [Accepted: 04/13/2015] [Indexed: 11/16/2022] Open
Abstract
AMT1-3 encodes the high affinity NH₄⁺ transporter in rice roots and is predominantly expressed under nitrogen starvation. In order to evaluate the effect of AMT1-3 gene on rice growth, nitrogen absorption and metabolism, we generated AMT1-3-overexpressing plants and analyzed the growth phenotype, yield, carbon and nitrogen metabolic status, and gene expression profiles. Although AMT1-3 mRNA accumulated in transgenic plants, these plants displayed significant decreases in growth when compared to the wild-type plants. The nitrogen uptake assay using a 15N tracer revealed poor nitrogen uptake ability in AMT1-3-overexpressing plants. We found significant decreases in AMT1-3-overexpressing plant leaf carbon and nitrogen content accompanied with a higher leaf C/N ratio. Significant changes in soluble proteins and carbohydrates were also observed in AMT1-3-overexpressing plants. In addition, metabolite profile analysis demonstrated significant changes in individual sugars, organic acids and free amino acids. Gene expression analysis revealed distinct expression patterns of genes that participate in carbon and nitrogen metabolism. Additionally, the correlation between the metabolites and gene expression patterns was consistent in AMT1-3-overexpressing plants under both low and high nitrogen growth conditions. Therefore, we hypothesized that the carbon and nitrogen metabolic imbalance caused by AMT1-3 overexpressing attributed to the poor growth and yield of transgenic plants.
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Affiliation(s)
- Aili Bao
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Microelement Research Center, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China.
| | - Zhijun Liang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Microelement Research Center, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China.
| | - Zhuqing Zhao
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Microelement Research Center, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China.
| | - Hongmei Cai
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Microelement Research Center, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China.
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15
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Yang S, Hao D, Cong Y, Jin M, Su Y. The rice OsAMT1;1 is a proton-independent feedback regulated ammonium transporter. PLANT CELL REPORTS 2015; 34:321-30. [PMID: 25433856 DOI: 10.1007/s00299-014-1709-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 10/20/2014] [Accepted: 11/19/2014] [Indexed: 05/22/2023]
Abstract
Functional identification of a relatively lower affinity ammonium transporter, OsAMT1;1, which is a proton-independent feedback regulated ammonium transporter in rice. Rice genome contains at least 12 ammonium transporters, though their functionality has not been clearly resolved. Here, we demonstrate the functional properties of OsAMT1;1 applying functional complementation and (15)NH4 (+) uptake determination in yeast cells in combination with electrophysiological measurements in Xenopus oocytes. Our results show that OsAMT1;1 is a NH4 (+) transporter with relatively lower affinity to NH4 (+) (110-129 μM in oocytes and yeast cells, respectively). Under our experimental conditions, OsAMT1;1-mediated NH4 (+) uptake or current is not significantly modulated by extra- or intracellular pH gradient, suggesting that this transporter probably functions as a NH4 (+) uniporter. Inhibition of yeast growth or currents elicited from oocytes by ammonium assimilation inhibitor L-methionine sulfoximine indicates that NH4 (+) transport by OsAMT1;1 is likely feedback regulated by accumulation of the substrate. In addition, effects of phosphorylation inhibitors imply that NH4 (+) uptake by OsAMT1;1 is also modulated by tyrosine-specific protein kinase or calcium-regulated serine/threonine-specific protein phosphatase involved phosphorylation processes.
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Affiliation(s)
- Shunying Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71, East Beijing Road, Nanjing, 210008, China
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Reddy MM, Ulaganathan K. Nitrogen Nutrition, Its Regulation and Biotechnological Approaches to Improve Crop Productivity. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/ajps.2015.618275] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Pérez-Tienda J, Corrêa A, Azcón-Aguilar C, Ferrol N. Transcriptional regulation of host NH₄⁺ transporters and GS/GOGAT pathway in arbuscular mycorrhizal rice roots. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 75:1-8. [PMID: 24361504 DOI: 10.1016/j.plaphy.2013.11.029] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 11/29/2013] [Indexed: 05/21/2023]
Abstract
Arbuscular mycorrhizal (AM) fungi play a key role in the nutrition of many land plants. AM roots have two pathways for nutrient uptake, directly through the root epidermis and root hairs and via AM fungal hyphae into root cortical cells, where arbuscules or hyphal coils provide symbiotic interfaces. Recent studies demonstrated that the AM symbiosis modifies the expression of plant transporter genes and that NH₄⁺ is the main form of N transported in the symbiosis. The aim of the present work was to get insights into the mycorrhizal N uptake pathway in Oryza sativa by analysing the expression of genes encoding ammonium transporters (AMTs), glutamine synthase (GS) and glutamate synthase (GOGAT) in roots colonized by the AM fungus Rhizophagus irregularis and grown under two N regimes. We found that the AM symbiosis down-regulated OsAMT1;1 and OsAMT1;3 expression at low-N, but not at high-N conditions, and induced, independently of the N status of the plant, a strong up-regulation of OsAMT3;1 expression. The AM-inducible NH₄⁺ transporter OsAMT3;1 belongs to the family 2 of plant AMTs and is phylogenetically related to the AM-inducible AMTs of other plant species. Moreover, for the first time we provide evidence of the specific induction of a GOGAT gene upon colonization with an AM fungus. These data suggest that OsAMT3;1 is likely involved in the mycorrhizal N uptake pathway in rice roots and that OsGOGAT2 plays a role in the assimilation of the NH₄⁺ supplied via the OsAMT3;1 AM-inducible transporter.
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Affiliation(s)
- Jacob Pérez-Tienda
- Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, CSIC, C. Profesor Albareda 1, 18008 Granada, Spain
| | - Ana Corrêa
- Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, CSIC, C. Profesor Albareda 1, 18008 Granada, Spain
| | - Concepción Azcón-Aguilar
- Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, CSIC, C. Profesor Albareda 1, 18008 Granada, Spain
| | - Nuria Ferrol
- Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, CSIC, C. Profesor Albareda 1, 18008 Granada, Spain.
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18
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Gaur VS, Singh US, Gupta AK, Kumar A. Influence of different nitrogen inputs on the members of ammonium transporter and glutamine synthetase genes in two rice genotypes having differential responsiveness to nitrogen. Mol Biol Rep 2012; 39:8035-44. [PMID: 22531935 DOI: 10.1007/s11033-012-1650-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 04/16/2012] [Indexed: 10/28/2022]
Abstract
Two aromatic rice genotypes, Pusa Basmati 1 (PB1) and Kalanamak 3119 (KN3119) having 120 and 30 kg/ha optimum nitrogen requirement respectively, to produce optimal yield, were chosen to understand their differential nitrogen responsiveness. Both the genotypes grown under increasing nitrogen inputs showed differences in seed/panicle, 1,000 seed weight, %nitrogen in the biomass and protein content in the seeds. All these parameters in PB1 were found to be in the increasing order in contrast to KN3119 which showed declined response on increasing nitrogen dose exceeding the normal dose indicating that both the genotypes respond differentially to the nitrogen inputs. Gene expression analysis of members of ammonium transporter gene family in flag leaves during active grain filling stage revealed that all the three members of OsAMT3 family genes (OsAMT1;1-3), only one member of OsAMT2 family i.e., OsAMT2;3 and the high affinity OsAMT1;1 were differentially expressed and were affected by different doses of nitrogen. In both the genotypes, both increase and decline in seed protein contents matched with the expressions levels of OsAMT1;1, OsGS1;1 and OsGS1;2 in the flag leaves during grain filling stage indicating that high nitrogen nutrition in KN3119 probably causes the repression of these genes which might be important during grain filling.
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Affiliation(s)
- Vikram Singh Gaur
- Department of Molecular Biology and Genetic Engineering, College of Basic Sciences and Humanities, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India
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