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Saifi F, Biró JB, Horváth B, Vizler C, Laczi K, Rákhely G, Kovács S, Kang M, Li D, Chen Y, Chen R, Domonkos Á, Kaló P. Two members of a Nodule-specific Cysteine-Rich (NCR) peptide gene cluster are required for differentiation of rhizobia in Medicago truncatula nodules. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 38923649 DOI: 10.1111/tpj.16871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 05/13/2024] [Accepted: 05/27/2024] [Indexed: 06/28/2024]
Abstract
Legumes have evolved a nitrogen-fixing symbiotic interaction with rhizobia, and this association helps them to cope with the limited nitrogen conditions in soil. The compatible interaction between the host plant and rhizobia leads to the formation of root nodules, wherein internalization and transition of rhizobia into their symbiotic form, termed bacteroids, occur. Rhizobia in the nodules of the Inverted Repeat-Lacking Clade legumes, including Medicago truncatula, undergo terminal differentiation, resulting in elongated and endoreduplicated bacteroids. This transition of endocytosed rhizobia is mediated by a large gene family of host-produced nodule-specific cysteine-rich (NCR) peptides in M. truncatula. Few NCRs have been recently found to be essential for complete differentiation and persistence of bacteroids. Here, we show that a M. truncatula symbiotic mutant FN9285, defective in the complete transition of rhizobia, is deficient in a cluster of NCR genes. More specifically, we show that the loss of the duplicated genes NCR086 and NCR314 in the A17 genotype, found in a single copy in Medicago littoralis R108, is responsible for the ineffective symbiotic phenotype of FN9285. The NCR086 and NCR314 gene pair encodes the same mature peptide but their transcriptional activity varies considerably. Nevertheless, both genes can restore the effective symbiosis in FN9285 indicating that their complementation ability does not depend on the strength of their expression activity. The identification of the NCR086/NCR314 peptide, essential for complete bacteroid differentiation, has extended the list of peptides, from a gene family of several hundred members, that are essential for effective nitrogen-fixing symbiosis in M. truncatula.
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Affiliation(s)
- Farheen Saifi
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - János Barnabás Biró
- HUN-REN Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
| | - Beatrix Horváth
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - Csaba Vizler
- HUN-REN Biological Research Centre, Institute of Biochemistry, Szeged, Hungary
| | - Krisztián Laczi
- HUN-REN Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
- Department of Biotechnology, University of Szeged, Szeged, Hungary
| | - Gábor Rákhely
- Department of Biotechnology, University of Szeged, Szeged, Hungary
- HUN-REN Biological Research Centre, Institute of Biophysics, Biological Research Center, Szeged, Hungary
| | - Szilárd Kovács
- HUN-REN Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
| | - Mingming Kang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Dengyao Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Yuhui Chen
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Rujin Chen
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Ágota Domonkos
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - Péter Kaló
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
- HUN-REN Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
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Berrabah F, Benaceur F, Yin C, Xin D, Magne K, Garmier M, Gruber V, Ratet P. Defense and senescence interplay in legume nodules. PLANT COMMUNICATIONS 2024; 5:100888. [PMID: 38532645 PMCID: PMC11009364 DOI: 10.1016/j.xplc.2024.100888] [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: 10/03/2023] [Revised: 02/05/2024] [Accepted: 03/23/2024] [Indexed: 03/28/2024]
Abstract
Immunity and senescence play a crucial role in the functioning of the legume symbiotic nodules. The miss-regulation of one of these processes compromises the symbiosis leading to death of the endosymbiont and the arrest of the nodule functioning. The relationship between immunity and senescence has been extensively studied in plant organs where a synergistic response can be observed. However, the interplay between immunity and senescence in the symbiotic organ is poorly discussed in the literature and these phenomena are often mixed up. Recent studies revealed that the cooperation between immunity and senescence is not always observed in the nodule, suggesting complex interactions between these two processes within the symbiotic organ. Here, we discuss recent results on the interplay between immunity and senescence in the nodule and the specificities of this relationship during legume-rhizobium symbiosis.
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Affiliation(s)
- Fathi Berrabah
- Faculty of Sciences, University Amar Telidji, 03000 Laghouat, Algeria; Research Unit of Medicinal Plants (RUMP), National Center of Biotechnology Research, CRBt, 25000 Constantine, Algeria.
| | - Farouk Benaceur
- Faculty of Sciences, University Amar Telidji, 03000 Laghouat, Algeria; Research Unit of Medicinal Plants (RUMP), National Center of Biotechnology Research, CRBt, 25000 Constantine, Algeria
| | - Chaoyan Yin
- Université Paris-Saclay, CNRS, INRAE, University of Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France; Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Dawei Xin
- Key Laboratory of Soybean Biology in the Chinese Ministry of Education, College of Agriculture, Northeast Agricultural University, Harbin 150030, China
| | - Kévin Magne
- Université Paris-Saclay, CNRS, INRAE, University of Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France; Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Marie Garmier
- Université Paris-Saclay, CNRS, INRAE, University of Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France; Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Véronique Gruber
- Université Paris-Saclay, CNRS, INRAE, University of Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France; Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France.
| | - Pascal Ratet
- Université Paris-Saclay, CNRS, INRAE, University of Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France; Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
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3
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Ghosh P, Chakraborty J. Exploring the role of symbiotic modifier peptidases in the legume - rhizobium symbiosis. Arch Microbiol 2024; 206:147. [PMID: 38462552 DOI: 10.1007/s00203-024-03920-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 03/12/2024]
Abstract
Legumes can establish a mutual association with soil-derived nitrogen-fixing bacteria called 'rhizobia' forming lateral root organs called root nodules. Rhizobia inside the root nodules get transformed into 'bacteroids' that can fix atmospheric nitrogen to ammonia for host plants in return for nutrients and shelter. A substantial 200 million tons of nitrogen is fixed annually through biological nitrogen fixation. Consequently, the symbiotic mechanism of nitrogen fixation is utilized worldwide for sustainable agriculture and plays a crucial role in the Earth's ecosystem. The development of effective nitrogen-fixing symbiosis between legumes and rhizobia is very specialized and requires coordinated signaling. A plethora of plant-derived nodule-specific cysteine-rich (NCR or NCR-like) peptides get actively involved in this complex and tightly regulated signaling process of symbiosis between some legumes of the IRLC (Inverted Repeat-Lacking Clade) and Dalbergioid clades and nitrogen-fixing rhizobia. Recent progress has been made in identifying two such peptidases that actively prevent bacterial differentiation, leading to symbiotic incompatibility. In this review, we outlined the functions of NCRs and two nitrogen-fixing blocking peptidases: HrrP (host range restriction peptidase) and SapA (symbiosis-associated peptidase A). SapA was identified through an overexpression screen from the Sinorhizobium meliloti 1021 core genome, whereas HrrP is inherited extra-chromosomally. Interestingly, both peptidases affect the symbiotic outcome by degrading the NCR peptides generated from the host plants. These NCR-degrading peptidases can shed light on symbiotic incompatibility, helping to elucidate the reasons behind the inefficiency of nitrogen fixation observed in certain groups of rhizobia with specific legumes.
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Affiliation(s)
- Prithwi Ghosh
- Department of Botany, Narajole Raj College, Vidyasagar University, Midnapore, 721211, India.
| | - Joydeep Chakraborty
- School of Plant Sciences and Food Security, Tel Aviv University, Tel-Aviv, Israel
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Chekan JR, Mydy LS, Pasquale MA, Kersten RD. Plant peptides - redefining an area of ribosomally synthesized and post-translationally modified peptides. Nat Prod Rep 2024. [PMID: 38411572 DOI: 10.1039/d3np00042g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Covering 1965 to February 2024Plants are prolific peptide chemists and are known to make thousands of different peptidic molecules. These peptides vary dramatically in their size, chemistry, and bioactivity. Despite their differences, all plant peptides to date are biosynthesized as ribosomally synthesized and post-translationally modified peptides (RiPPs). Decades of research in plant RiPP biosynthesis have extended the definition and scope of RiPPs from microbial sources, establishing paradigms and discovering new families of biosynthetic enzymes. The discovery and elucidation of plant peptide pathways is challenging due to repurposing and evolution of housekeeping genes as both precursor peptides and biosynthetic enzymes and due to the low rates of gene clustering in plants. In this review, we highlight the chemistry, biosynthesis, and function of the known RiPP classes from plants and recommend a nomenclature for the recent addition of BURP-domain-derived RiPPs termed burpitides. Burpitides are an emerging family of cyclic plant RiPPs characterized by macrocyclic crosslinks between tyrosine or tryptophan side chains and other amino acid side chains or their peptide backbone that are formed by copper-dependent BURP-domain-containing proteins termed burpitide cyclases. Finally, we review the discovery of plant RiPPs through bioactivity-guided, structure-guided, and gene-guided approaches.
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Affiliation(s)
- Jonathan R Chekan
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC, USA.
| | - Lisa S Mydy
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA.
| | - Michael A Pasquale
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC, USA.
| | - Roland D Kersten
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA.
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Alhhazmi AA, Alluhibi SS, Alhujaily R, Alenazi ME, Aljohani TL, Al-Jazzar AAT, Aljabri AD, Albaqami R, Almutairi D, Alhelali LK, Albasri HM, Almutawif YA, Alturkostani MA, Almutairi AZ. Novel antimicrobial peptides identified in legume plant, Medicago truncatula. Microbiol Spectr 2024; 12:e0182723. [PMID: 38236024 PMCID: PMC10845954 DOI: 10.1128/spectrum.01827-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 12/16/2023] [Indexed: 01/19/2024] Open
Abstract
One of the major issues in healthcare today is antibiotic resistance. Antimicrobial peptides (AMPs), a subclass of host defense peptides, have been suggested as a viable solution for the multidrug resistance problem. Legume plants express more than 700 nodule-specific cysteine-rich (NCR) peptides. Three NCR peptides (NCR094, NCR888, and NCR992) were predicted to have antimicrobial activity using in silico AMP prediction programs. This study focused on investigating the roles of the NCRs in antimicrobial activity and antibiofilm activity, followed by in vitro toxicity profiling. Different variants were synthesized, i.e., mutated and truncated derivatives. The effect on the growth of Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA) was monitored post-treatment, and survived cells were counted using an in vitro and ex vivo killing assay. The antibiofilm assay was conducted using subinhibitory concentrations of the NCRs and monitoring K. pneumoniae biomass, followed by crystal violet staining. The cytotoxicity profile was evaluated using erythrocyte hemolysis and leukemia (K562) cell line toxicity assays. Out of the NCRs, NCR094 and NCR992 displayed mainly in vitro and ex vivo bactericidal activity on K. pneumoniae. NCR094 wild type (WT) and NCR992 eradicated K. pneumoniae at different potency; NCR094 and NCR992 killed K. pneumoniae completely at 25 and 50 µM, respectively. However, both peptides in the wild type showed negligible bactericidal effect on MRSA in vitro and ex vivo. NCR094 and its derivatives relatively retained the antimicrobial activity on K. pneumoniae in vitro and ex vivo. NCR992 WT lost its antimicrobial activity on K. pneumoniae ex vivo, yet the different truncated and mutated variants retained some of the antimicrobial role ex vivo. All the different variants of NCR094 had no effect on MRSA in vitro and ex vivo. Similarly, NCR992's variants had a negligible bactericidal role on MRSA in vitro, yet the truncated variants had a significantly high bactericidal effect on MRSA ex vivo. NCR094.3 (cystine replacement variant) and NCR992.1 displayed significant antibiofilm activity more than 90%. NCR992.3 and NCR992.2 displayed more than 50% of antibiofilm activity. All the NCR094 forms had no toxicity, except NCR094.1 (49.38%, SD ± 3.46) and all NCR992 forms (63%-93%), which were above the cutoff (20%). Only NCR992.2 showed low toxicity on K562 (24.8%, SD ± 3.40), yet above the 20% cutoff. This study provided preliminary antimicrobial and safety data for the potential use of these peptides for therapeutical applications.IMPORTANCEThe discovery of new antibiotics is urgently needed, given the global expansion of antibiotic-resistant bacteria and the rising mortality rate. One of the initial lines of defense against microbial infections is antimicrobial peptides (AMPs). Plants can express hundreds of such AMPs as defensins and defensin-like peptides. The nodule-specific cysteine-rich (NCR) peptides are a class of defensin-like peptides that have evolved in rhizobial-legume symbioses. This study screened the antimicrobial activity of a subset of NCR sequences using online computational AMP prediction algorithms. Two novel NCRs, NCR094 and NCR992, with different variants were identified to exhibit antimicrobial activity with various potency on two problematic pathogens, K. pneumoniae and MRSA, using in vitro and ex vivo killing assays. Yet, one variant, NCR094.3, had no toxicity toward human cells and displayed antibiofilm activity, which make it a promising lead for antimicrobial drug development.
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Affiliation(s)
- Areej A. Alhhazmi
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Sarah S. Alluhibi
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Rahaf Alhujaily
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Maymona E. Alenazi
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Taif L. Aljohani
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Al-Anoud T. Al-Jazzar
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Ahaad D. Aljabri
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Razan Albaqami
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Dalal Almutairi
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Lujain K. Alhelali
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
| | - Hibah M. Albasri
- Department of Biology, College of Science, Taibah University, Medina, Saudi Arabia
| | - Yahya A. Almutawif
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia
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Güngör B, Biró JB, Domonkos Á, Horváth B, Kaló P. Targeted mutagenesis of Medicago truncatula Nodule-specific Cysteine-Rich (NCR) genes using the Agrobacterium rhizogenes-mediated CRISPR/Cas9 system. Sci Rep 2023; 13:20676. [PMID: 38001333 PMCID: PMC10673856 DOI: 10.1038/s41598-023-47608-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
The host-produced nodule specific cysteine-rich (NCR) peptides control the terminal differentiation of endosymbiotic rhizobia in the nodules of IRLC legumes. Although the Medicago truncatula genome encodes about 700 NCR peptides, only few of them have been proven to be crucial for nitrogen-fixing symbiosis. In this study, we applied the CRISPR/Cas9 gene editing technology to generate knockout mutants of NCR genes for which no genetic or functional data were previously available. We have developed a workflow to analyse the mutation and the symbiotic phenotype of individual nodules formed on Agrobacterium rhizogenes-mediated transgenic hairy roots. The selected NCR genes were successfully edited by the CRISPR/Cas9 system and nodules formed on knockout hairy roots showed wild type phenotype indicating that peptides NCR068, NCR089, NCR128 and NCR161 are not essential for symbiosis between M. truncatula Jemalong and Sinorhizobium medicae WSM419. We regenerated stable mutants edited for the NCR068 from hairy roots obtained by A. rhizogenes-mediated transformation. The analysis of the symbiotic phenotype of stable ncr068 mutants showed that peptide NCR068 is not required for symbiosis with S. meliloti strains 2011 and FSM-MA either. Our study reports that gene editing can help to elicit the role of certain NCRs in symbiotic nitrogen fixation.
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Affiliation(s)
- Berivan Güngör
- Institute of Plant Biology, HUN-REN Biological Research Centre, Szeged, Hungary
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - János Barnabás Biró
- Institute of Plant Biology, HUN-REN Biological Research Centre, Szeged, Hungary
| | - Ágota Domonkos
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - Beatrix Horváth
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - Péter Kaló
- Institute of Plant Biology, HUN-REN Biological Research Centre, Szeged, Hungary.
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary.
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Ma Y, Zhu W, Zhao W, Zhang B, He J, Zhang C, Li P, Hu Y, Zhou Z, Yan Z, Li J, Cai W, Ren G, Chen R. MtESN2 is a subgroup II sulphate transporter required for symbiotic nitrogen fixation and prevention of nodule early senescence in Medicago truncatula. PLANT, CELL & ENVIRONMENT 2023; 46:3558-3574. [PMID: 37545348 DOI: 10.1111/pce.14678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 07/07/2023] [Accepted: 07/24/2023] [Indexed: 08/08/2023]
Abstract
Adequate distribution of mineral sulphur (S) nutrition to nodules mediated by sulphate transporters is crucial for nitrogen fixation in symbiosis establishment process. However, the molecular mechanisms underlying this process remain largely unknown. In this study, we characterized the function of Early Senescent Nodule 2 (MtESN2), a gene crucial to nitrogen fixation in Medicago truncatula. Mutations in MtESN2 resulted in severe developmental and functional defects including dwarf shoots, early senescent nodules, and lower nitrogenase activity under symbiotic conditions compared to wild-type plants. MtESN2 encodes an M. truncatula sulphate transporter that is expressed only in roots and nodules, with the highest expression levels in the transition zone and nitrogen-fixing zone of nodules. MtESN2 exhibited sulphate transport activity when expressed in yeast. Immunolocalization analysis showed that MtESN2-yellow fluorescent protein fusion protein was localized to the plasma membranes of both uninfected and infected cells of nodules, where it might transport sulphate into both rhizobia-infected and uninfected cells within the nodules. Our results reveal an unreported sulphate transporter that contributes to effective symbiosis and prevents nodule early senescence in M. truncatula.
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Affiliation(s)
- Yanlin Ma
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
- State Key Laboratory of Grassland Agro-Ecosystem, College of Ecology, Lanzhou University, Lanzhou, China
| | - Weike Zhu
- College of Cuiying Honors, Lanzhou University, Lanzhou, China
| | - Weichen Zhao
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Beihong Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Juanxia He
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Chenyan Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Peng Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Yibo Hu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Zaicai Zhou
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Zezhang Yan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Juanjuan Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Wenkai Cai
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Guangpeng Ren
- State Key Laboratory of Grassland Agro-Ecosystem, College of Ecology, Lanzhou University, Lanzhou, China
| | - Rujin Chen
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
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8
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Zhang R, Shen Y, He J, Zhang C, Ma Y, Sun C, Song X, Li L, Zhang S, Biró JB, Saifi F, Kaló P, Chen R. Nodule-specific cysteine-rich peptide 343 is required for symbiotic nitrogen fixation in Medicago truncatula. PLANT PHYSIOLOGY 2023; 193:1897-1912. [PMID: 37555448 DOI: 10.1093/plphys/kiad454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 07/14/2023] [Indexed: 08/10/2023]
Abstract
Symbiotic interactions between legumes and rhizobia lead to the development of root nodules and nitrogen fixation by differentiated bacteroids within nodules. Differentiation of the endosymbionts is reversible or terminal, determined by plant effectors. In inverted repeat lacking clade legumes, nodule-specific cysteine-rich (NCR) peptides control the terminal differentiation of bacteroids. Medicago truncatula contains ∼700 NCR-coding genes. However, the role of few NCR peptides has been demonstrated. Here, we report characterization of fast neutron 2106 (FN2106), a symbiotic nitrogen fixation defective (fix-) mutant of M. truncatula. Using a transcript-based approach, together with linkage and complementation tests, we showed that loss-of-function of NCR343 results in impaired bacteroid differentiation and/or maintenance and premature nodule senescence of the FN2106 mutant. NCR343 was specifically expressed in nodules. Subcellular localization studies showed that the functional NCR343-YFP fusion protein colocalizes with bacteroids in symbiosomes in infected nodule cells. Transcriptomic analyses identified senescence-, but not defense-related genes, as being significantly upregulated in ncr343 (FN2106) nodules. Taken together, results from our phenotypic and transcriptomic analyses of a loss-of-function ncr343 mutant demonstrate an essential role of NCR343 in bacteroid differentiation and/or maintenance required for symbiotic nitrogen fixation.
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Affiliation(s)
- Rui Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Yitong Shen
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Juanxia He
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Chenyan Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Yelin Ma
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Chenghui Sun
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Xiaopan Song
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Li Li
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Sisi Zhang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
| | - János Barnabás Biró
- Institute of Plant Biology, Biological Research Centre, Eötvös Lóránd Research Network, Szeged, Hungary
| | - Farheen Saifi
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - Péter Kaló
- Institute of Plant Biology, Biological Research Centre, Eötvös Lóránd Research Network, Szeged, Hungary
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - Rujin Chen
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China
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9
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Gao F, Yang J, Zhai N, Zhang C, Ren X, Zeng Y, Chen Y, Chen R, Pan H. NCR343 is required to maintain the viability of differentiated bacteroids in nodule cells in Medicago truncatula. THE NEW PHYTOLOGIST 2023; 240:815-829. [PMID: 37533094 DOI: 10.1111/nph.19180] [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: 03/16/2023] [Accepted: 07/13/2023] [Indexed: 08/04/2023]
Abstract
Bacteroid (name for rhizobia inside nodule cells) differentiation is a prerequisite for successful nitrogen-fixing symbiosis. In certain legumes, under the regulation of host proteins, for example, a large group of NCR (nodule cysteine rich) peptides, bacteroids undergo irreversible terminal differentiation. This process causes them to lose the ability to propagate inside nodule cells while boosting their competency for nitrogen fixation. How host cells maintain the viability of differentiated bacteroids while maximizing their nitrogen-reducing activities remains elusive. Here, through mutant screen, map-based cloning, and genetic complementation, we find that NCR343 is required for the viability of differentiated bacteroids. In Medicago truncatula debino1 mutant, differentiated bacteroids decay prematurely, and NCR343 is proved to be the casual gene for debino1. NCR343 is mainly expressed in the nodule fixation zone, where bacteroids are differentiated. In nodule cells, mature NCR343 peptide is secreted into the symbiosomes. RNA-Seq assay shows that many stress-responsive genes are significantly induced in debino1 bacteroids. Additionally, a group of stress response-related rhizobium proteins are identified as putative interacting partners of NCR343. In summary, our findings demonstrate that beyond promoting bacteroid differentiation, NCR peptides are also required in maintaining the viability of differentiated bacteroids.
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Affiliation(s)
- Fengzhan Gao
- College of Biology, Hunan University, Changsha, 410082, China
| | - Jian Yang
- College of Biology, Hunan University, Changsha, 410082, China
| | - Niu Zhai
- Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, 450001, China
| | - Chao Zhang
- College of Biology, Hunan University, Changsha, 410082, China
| | - Xinru Ren
- College of Biology, Hunan University, Changsha, 410082, China
| | - Yating Zeng
- College of Biology, Hunan University, Changsha, 410082, China
| | - Yuhui Chen
- College of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Rujin Chen
- College of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Huairong Pan
- College of Biology, Hunan University, Changsha, 410082, China
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10
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Bustamante JA, Ceron JS, Gao IT, Ramirez HA, Aviles MV, Bet Adam D, Brice JR, Cuellar RA, Dockery E, Jabagat MK, Karp DG, Lau JKO, Li S, Lopez-Magaña R, Moore RR, Morin BKR, Nzongo J, Rezaeihaghighi Y, Sapienza-Martinez J, Tran TTK, Huang Z, Duthoy AJ, Barnett MJ, Long SR, Chen JC. A protease and a lipoprotein jointly modulate the conserved ExoR-ExoS-ChvI signaling pathway critical in Sinorhizobium meliloti for symbiosis with legume hosts. PLoS Genet 2023; 19:e1010776. [PMID: 37871041 PMCID: PMC10659215 DOI: 10.1371/journal.pgen.1010776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 11/20/2023] [Accepted: 10/11/2023] [Indexed: 10/25/2023] Open
Abstract
Sinorhizobium meliloti is a model alpha-proteobacterium for investigating microbe-host interactions, in particular nitrogen-fixing rhizobium-legume symbioses. Successful infection requires complex coordination between compatible host and endosymbiont, including bacterial production of succinoglycan, also known as exopolysaccharide-I (EPS-I). In S. meliloti EPS-I production is controlled by the conserved ExoS-ChvI two-component system. Periplasmic ExoR associates with the ExoS histidine kinase and negatively regulates ChvI-dependent expression of exo genes, necessary for EPS-I synthesis. We show that two extracytoplasmic proteins, LppA (a lipoprotein) and JspA (a lipoprotein and a metalloprotease), jointly influence EPS-I synthesis by modulating the ExoR-ExoS-ChvI pathway and expression of genes in the ChvI regulon. Deletions of jspA and lppA led to lower EPS-I production and competitive disadvantage during host colonization, for both S. meliloti with Medicago sativa and S. medicae with M. truncatula. Overexpression of jspA reduced steady-state levels of ExoR, suggesting that the JspA protease participates in ExoR degradation. This reduction in ExoR levels is dependent on LppA and can be replicated with ExoR, JspA, and LppA expressed exogenously in Caulobacter crescentus and Escherichia coli. Akin to signaling pathways that sense extracytoplasmic stress in other bacteria, JspA and LppA may monitor periplasmic conditions during interaction with the plant host to adjust accordingly expression of genes that contribute to efficient symbiosis. The molecular mechanisms underlying host colonization in our model system may have parallels in related alpha-proteobacteria.
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Affiliation(s)
- Julian A. Bustamante
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Josue S. Ceron
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Ivan Thomas Gao
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Hector A. Ramirez
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Milo V. Aviles
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Demsin Bet Adam
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Jason R. Brice
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Rodrigo A. Cuellar
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Eva Dockery
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Miguel Karlo Jabagat
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Donna Grace Karp
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Joseph Kin-On Lau
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Suling Li
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Raymondo Lopez-Magaña
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Rebecca R. Moore
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Bethany Kristi R. Morin
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Juliana Nzongo
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Yasha Rezaeihaghighi
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Joseph Sapienza-Martinez
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Tuyet Thi Kim Tran
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Zhenzhong Huang
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Aaron J. Duthoy
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Melanie J. Barnett
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Sharon R. Long
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Joseph C. Chen
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
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11
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Feng YZ, Zhu QF, Xue J, Chen P, Yu Y. Shining in the dark: the big world of small peptides in plants. ABIOTECH 2023; 4:238-256. [PMID: 37970469 PMCID: PMC10638237 DOI: 10.1007/s42994-023-00100-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 02/24/2023] [Indexed: 11/17/2023]
Abstract
Small peptides represent a subset of dark matter in plant proteomes. Through differential expression patterns and modes of action, small peptides act as important regulators of plant growth and development. Over the past 20 years, many small peptides have been identified due to technical advances in genome sequencing, bioinformatics, and chemical biology. In this article, we summarize the classification of plant small peptides and experimental strategies used to identify them as well as their potential use in agronomic breeding. We review the biological functions and molecular mechanisms of small peptides in plants, discuss current problems in small peptide research and highlight future research directions in this field. Our review provides crucial insight into small peptides in plants and will contribute to a better understanding of their potential roles in biotechnology and agriculture.
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Affiliation(s)
- Yan-Zhao Feng
- Guangdong Key Laboratory of Crop Germplasm Resources Preservation and Utilization, Key Laboratory of South China Modern Biological Seed Industry, Ministry of Agriculture and Rural Affairs, Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 China
| | - Qing-Feng Zhu
- Guangdong Key Laboratory of Crop Germplasm Resources Preservation and Utilization, Key Laboratory of South China Modern Biological Seed Industry, Ministry of Agriculture and Rural Affairs, Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 China
| | - Jiao Xue
- Guangdong Key Laboratory of Crop Germplasm Resources Preservation and Utilization, Key Laboratory of South China Modern Biological Seed Industry, Ministry of Agriculture and Rural Affairs, Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 China
| | - Pei Chen
- Guangdong Key Laboratory of Crop Germplasm Resources Preservation and Utilization, Key Laboratory of South China Modern Biological Seed Industry, Ministry of Agriculture and Rural Affairs, Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 China
| | - Yang Yu
- Guangdong Key Laboratory of Crop Germplasm Resources Preservation and Utilization, Key Laboratory of South China Modern Biological Seed Industry, Ministry of Agriculture and Rural Affairs, Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 China
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12
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Shen Y, Ma Y, Li D, Kang M, Pei Y, Zhang R, Tao W, Huang S, Song W, Li Y, Huang W, Wang D, Chen Y. Biological and genomic analysis of a symbiotic nitrogen fixation defective mutant in Medicago truncatula. FRONTIERS IN PLANT SCIENCE 2023; 14:1209664. [PMID: 37457346 PMCID: PMC10345209 DOI: 10.3389/fpls.2023.1209664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 06/13/2023] [Indexed: 07/18/2023]
Abstract
Medicago truncatula has been selected as one of the model legume species for gene functional studies. To elucidate the functions of the very large number of genes present in plant genomes, genetic mutant resources are very useful and necessary tools. Fast Neutron (FN) mutagenesis is effective in inducing deletion mutations in genomes of diverse species. Through this method, we have generated a large mutant resource in M. truncatula. This mutant resources have been used to screen for different mutant using a forward genetics methods. We have isolated and identified a large amount of symbiotic nitrogen fixation (SNF) deficiency mutants. Here, we describe the detail procedures that are being used to characterize symbiotic mutants in M. truncatula. In recent years, whole genome sequencing has been used to speed up and scale up the deletion identification in the mutant. Using this method, we have successfully isolated a SNF defective mutant FN007 and identified that it has a large segment deletion on chromosome 3. The causal deletion in the mutant was confirmed by tail PCR amplication and sequencing. Our results illustrate the utility of whole genome sequencing analysis in the characterization of FN induced deletion mutants for gene discovery and functional studies in the M. truncatula. It is expected to improve our understanding of molecular mechanisms underlying symbiotic nitrogen fixation in legume plants to a great extent.
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13
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Nguyen CX, Dohnalkova A, Hancock CN, Kirk KR, Stacey G, Stacey MG. Critical role for uricase and xanthine dehydrogenase in soybean nitrogen fixation and nodule development. THE PLANT GENOME 2023; 16:e20171. [PMID: 34904377 DOI: 10.1002/tpg2.20172] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 09/22/2021] [Indexed: 06/14/2023]
Abstract
De novo purine biosynthesis is required for the incorporation of fixed nitrogen in ureide exporting nodules, as formed on soybean [Glycine max (L.) Merr.] roots. However, in many cases, the enzymes involved in this pathway have been deduced strictly from genome annotations with little direct genetic evidence, such as mutant studies, to confirm their biochemical function or importance to nodule development. While efforts to develop large mutant collections of soybean are underway, research on this plant is still hampered by the inability to obtain mutations in any specific gene of interest. Using a forward genetic approach, as well as CRISPR/Cas9 gene editing via Agrobacterium rhizogenes-mediated hairy root transformation, we identified and characterized the role of GmUOX (Uricase) and GmXDH (Xanthine Dehydrogenase) in nitrogen fixation and nodule development in soybean. The gmuox knockout soybean mutants displayed nitrogen deficiency chlorosis and early nodule senescence, as exemplified by the reduced nitrogenase (acetylene reduction) activity in nodules, the internal greenish-white internal appearance of nodules, and diminished leghemoglobin production. In addition, gmuox1 nodules showed collapsed infected cells with degraded cytoplasm, aggregated bacteroids with no discernable symbiosome membranes, and increased formation of poly-β-hydroxybutyrate granules. Similarly, knockout gmxdh mutant nodules, generated with the CRISPR/Cas9 system, also exhibited early nodule senescence. These genetic studies confirm the critical role of the de novo purine metabolisms pathway not only in the incorporation of fixed nitrogen but also in the successful development of a functional, nitrogen-fixing nodule. Furthermore, these studies demonstrate the great utility of the CRISPR/Cas9 system for studying root-associated gene traits when coupled with hairy root transformation.
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Affiliation(s)
- Cuong X Nguyen
- Division of Plant Sciences, Univ. of Missouri, Columbia, MO, 65211, USA
| | - Alice Dohnalkova
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - C Nathan Hancock
- Dep. of Biology & Geology, Univ. of South Carolina, Aiken, SC, 29801, USA
| | - Kendall R Kirk
- Edisto Research & Education Center, Clemson Univ., Blackville, SC, 29817, USA
| | - Gary Stacey
- Division of Plant Sciences, Univ. of Missouri, Columbia, MO, 65211, USA
- Division of Biochemistry, Univ. of Missouri, Columbia, MO, 65211, USA
| | - Minviluz G Stacey
- Division of Plant Sciences, Univ. of Missouri, Columbia, MO, 65211, USA
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14
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Jardinaud MF, Carrere S, Gourion B, Gamas P. Symbiotic Nodule Development and Efficiency in the Medicago truncatula Mtefd-1 Mutant Is Highly Dependent on Sinorhizobium Strains. PLANT & CELL PHYSIOLOGY 2023; 64:27-42. [PMID: 36151948 DOI: 10.1093/pcp/pcac134] [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: 06/30/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Symbiotic nitrogen fixation (SNF) can play a key role in agroecosystems to reduce the negative impact of nitrogen fertilizers. Its efficiency is strongly affected by the combination of bacterial and plant genotypes, but the mechanisms responsible for the differences in the efficiency of rhizobium strains are not well documented. In Medicago truncatula, SNF has been mostly studied using model systems, such as M. truncatula A17 in interaction with Sinorhizobium meliloti Sm2011. Here we analyzed both the wild-type (wt) A17 and the Mtefd-1 mutant in interaction with five S. meliloti and two Sinorhizobium medicae strains. ETHYLENE RESPONSE FACTOR REQUIRED FOR NODULE DIFFERENTIATION (MtEFD) encodes a transcription factor, which contributes to the control of nodule number and differentiation in M. truncatula. We found that, in contrast to Sm2011, four strains induce functional (Fix+) nodules in Mtefd-1, although less efficient for SNF than in wt A17. In contrast, the Mtefd-1 hypernodulation phenotype is not strain-dependent. We compared the plant nodule transcriptomes in response to SmBL225C, a highly efficient strain with A17, versus Sm2011, in wt and Mtefd-1 backgrounds. This revealed faster nodule development with SmBL225C and early nodule senescence with Sm2011. These RNA sequencing analyses allowed us to identify candidate plant factors that could drive the differential nodule phenotype. In conclusion, this work shows the value of having a set of rhizobium strains to fully evaluate the biological importance of a plant symbiotic gene.
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Affiliation(s)
- Marie-Françoise Jardinaud
- LIPME, INRAE, CNRS, Université de Toulouse, 24 Chemin de Borde Rouge, Auzeville-Tolosane 31320, France
| | - Sebastien Carrere
- LIPME, INRAE, CNRS, Université de Toulouse, 24 Chemin de Borde Rouge, Auzeville-Tolosane 31320, France
| | - Benjamin Gourion
- LIPME, INRAE, CNRS, Université de Toulouse, 24 Chemin de Borde Rouge, Auzeville-Tolosane 31320, France
| | - Pascal Gamas
- LIPME, INRAE, CNRS, Université de Toulouse, 24 Chemin de Borde Rouge, Auzeville-Tolosane 31320, France
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15
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Competitiveness and Phylogenetic Relationship of Rhizobial Strains with Different Symbiotic Efficiency in Trifolium repens: Conversion of Parasitic into Non-Parasitic Rhizobia by Natural Symbiotic Gene Transfer. BIOLOGY 2023; 12:biology12020243. [PMID: 36829520 PMCID: PMC9953144 DOI: 10.3390/biology12020243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/25/2023] [Accepted: 01/27/2023] [Indexed: 02/09/2023]
Abstract
In Uruguayan soils, populations of native and naturalized rhizobia nodulate white clover. These populations include efficient rhizobia but also parasitic strains, which compete for nodule occupancy and hinder optimal nitrogen fixation by the grassland. Nodulation competitiveness assays using gusA-tagged strains proved a high nodule occupancy by the inoculant strain U204, but this was lower than the strains with intermediate efficiencies, U268 and U1116. Clover biomass production only decreased when the parasitic strain UP3 was in a 99:1 ratio with U204, but not when UP3 was at equal or lower numbers than U204. Based on phylogenetic analyses, strains with different efficiencies did not cluster together, and U1116 grouped with the parasitic strains. Our results suggest symbiotic gene transfer from an effective strain to U1116, thereby improving its symbiotic efficiency. Genome sequencing of U268 and U204 strains allowed us to assign them to species Rhizobium redzepovicii, the first report of this species nodulating clover, and Rhizobium leguminosarun, respectively. We also report the presence of hrrP- and sapA-like genes in the genomes of WSM597, U204, and U268 strains, which are related to symbiotic efficiency in rhizobia. Interestingly, we report here chromosomally located hrrP-like genes.
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16
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Gourion B. NCRs make the difference. NATURE PLANTS 2023; 9:199-200. [PMID: 36690787 DOI: 10.1038/s41477-023-01346-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Affiliation(s)
- Benjamin Gourion
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France.
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17
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Singh J, Valdés-López O. A nodule peptide confiscates haem to promote iron uptake in rhizobia. TRENDS IN PLANT SCIENCE 2023; 28:125-127. [PMID: 36443185 DOI: 10.1016/j.tplants.2022.11.005] [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: 09/12/2022] [Revised: 11/09/2022] [Accepted: 11/16/2022] [Indexed: 06/16/2023]
Abstract
Nodule cysteine-rich (NCR) peptides have a major role in the differentiation of endocytosed bacteria into nitrogen-fixing bacteroids. A recent paper by Sankari et al. indicates that NCR247 is essential for the uptake of iron, a mineral nutrient required for nitrogenase activity. Furthermore, the special ability of NCR247 to sequester haem suggests potential applications for human health.
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Affiliation(s)
- Jawahar Singh
- Laboratorio de Genómica Funcional de Leguminosas, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla 54090, México
| | - Oswaldo Valdés-López
- Laboratorio de Genómica Funcional de Leguminosas, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla 54090, México.
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18
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Zhang S, Wang T, Lima RM, Pettkó-Szandtner A, Kereszt A, Downie JA, Kondorosi E. Widely conserved AHL transcription factors are essential for NCR gene expression and nodule development in Medicago. NATURE PLANTS 2023; 9:280-288. [PMID: 36624259 PMCID: PMC9946822 DOI: 10.1038/s41477-022-01326-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 12/02/2022] [Indexed: 05/13/2023]
Abstract
Symbiotic nitrogen fixation by Rhizobium bacteria in the cells of legume root nodules alleviates the need for nitrogen fertilizers. Nitrogen fixation requires the endosymbionts to differentiate into bacteroids which can be reversible or terminal. The latter is controlled by the plant, it is more beneficial and has evolved in multiple clades of the Leguminosae family. The plant effectors of terminal differentiation in inverted repeat-lacking clade legumes (IRLC) are nodule-specific cysteine-rich (NCR) peptides, which are absent in legumes such as soybean where there is no terminal differentiation of rhizobia. It was assumed that NCRs co-evolved with specific transcription factors, but our work demonstrates that expression of NCR genes does not require NCR-specific transcription factors. Introduction of the Medicago truncatula NCR169 gene under its own promoter into soybean roots resulted in its nodule-specific expression, leading to bacteroid changes associated with terminal differentiation. We identified two AT-Hook Motif Nuclear Localized (AHL) transcription factors from both M. truncatula and soybean nodules that bound to AT-rich sequences in the NCR169 promoter inducing its expression. Whereas mutation of NCR169 arrested bacteroid development at a late stage, the absence of MtAHL1 or MtAHL2 completely blocked bacteroid differentiation indicating that they also regulate other NCR genes required for the development of nitrogen-fixing nodules. Regulation of NCRs by orthologous transcription factors in non-IRLC legumes opens up the possibility of increasing the efficiency of nitrogen fixation in legumes lacking NCRs.
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Affiliation(s)
- Senlei Zhang
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
| | - Ting Wang
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
| | - Rui M Lima
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
| | | | - Attila Kereszt
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
| | - J Allan Downie
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
- John Innes Centre, Norwich, UK
| | - Eva Kondorosi
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary.
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19
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Howan DHO, Jenei S, Szolomajer J, Endre G, Kondorosi É, Tóth GK. Enhanced Antibacterial Activity of Substituted Derivatives of NCR169C Peptide. Int J Mol Sci 2023; 24:ijms24032694. [PMID: 36769017 PMCID: PMC9917201 DOI: 10.3390/ijms24032694] [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: 01/16/2023] [Revised: 01/25/2023] [Accepted: 01/26/2023] [Indexed: 02/04/2023] Open
Abstract
Medicago truncatula in symbiosis with its rhizobial bacterium partner produces more than 700 nodule-specific cysteine-rich (NCR) peptides with diverse physicochemical properties. Most of the cationic NCR peptides have antimicrobial activity and the potential to tackle antimicrobial resistance with their novel modes of action. This work focuses on the antibacterial activity of the NCR169 peptide derivatives as we previously demonstrated that the C-terminal sequence of NCR169 (NCR169C17-38) has antifungal activity, affecting the viability, morphology, and biofilm formation of various Candida species. Here, we show that NCR169C17-38 and its various substituted derivatives are also able to kill ESKAPE pathogens such as Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli. The replacement of the two cysteines with serines enhanced the antimicrobial activity against most of the tested bacteria, indicating that the formation of a disulfide bridge is not required. As tryptophan can play role in the interaction with bacterial membranes and thus in antibacterial activity, we replaced the tryptophans in the NCR169C17-38C12,17/S sequence with various modified tryptophans, namely 5-methyl tryptophan, 5-fluoro tryptophan, 6-fluoro tryptophan, 7-aza tryptophan, and 5-methoxy tryptophan, in the synthesis of NCR169C17-38C12,17/S analogs. The results demonstrate that the presence of modified fluorotryptophans can significantly enhance the antimicrobial activity without notable hemolytic effect, and this finding could be beneficial for the further development of new AMPs from the members of the NCR peptide family.
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Affiliation(s)
- Dian H. O. Howan
- Department of Medical Chemistry, Albert Szent-Györgyi Medical School, University of Szeged, H-6720 Szeged, Hungary
| | - Sándor Jenei
- Biological Research Centre, Institute of Plant Biology, H-6726 Szeged, Hungary
| | - János Szolomajer
- Department of Medical Chemistry, Albert Szent-Györgyi Medical School, University of Szeged, H-6720 Szeged, Hungary
| | - Gabriella Endre
- Biological Research Centre, Institute of Plant Biology, H-6726 Szeged, Hungary
| | - Éva Kondorosi
- Biological Research Centre, Institute of Plant Biology, H-6726 Szeged, Hungary
| | - Gábor K. Tóth
- Department of Medical Chemistry, Albert Szent-Györgyi Medical School, University of Szeged, H-6720 Szeged, Hungary
- MTA-SZTE Biomimetic Systems Research Group, Albert Szent-Györgyi Medical School, University of Szeged, H-6720 Szeged, Hungary
- Correspondence:
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20
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Berrabah F, Bernal G, Elhosseyn AS, El Kassis C, L’Horset R, Benaceur F, Wen J, Mysore KS, Garmier M, Gourion B, Ratet P, Gruber V. Insight into the control of nodule immunity and senescence during Medicago truncatula symbiosis. PLANT PHYSIOLOGY 2023; 191:729-746. [PMID: 36305683 PMCID: PMC9806560 DOI: 10.1093/plphys/kiac505] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/25/2022] [Indexed: 06/16/2023]
Abstract
Medicago (Medicago truncatula) establishes a symbiosis with the rhizobia Sinorhizobium sp, resulting in the formation of nodules where the bacteria fix atmospheric nitrogen. The loss of immunity repression or early senescence activation compromises symbiont survival and leads to the formation of nonfunctional nodules (fix-). Despite many studies exploring an overlap between immunity and senescence responses outside the nodule context, the relationship between these processes in the nodule remains poorly understood. To investigate this phenomenon, we selected and characterized three Medicago mutants developing fix- nodules and showing senescence responses. Analysis of specific defense (PATHOGENESIS-RELATED PROTEIN) or senescence (CYSTEINE PROTEASE) marker expression demonstrated that senescence and immunity seem to be antagonistic in fix- nodules. The growth of senescence mutants on non-sterile (sand/perlite) substrate instead of sterile in vitro conditions decreased nodule senescence and enhanced defense, indicating that environment can affect the immunity/senescence balance. The application of wounding stress on wild-type (WT) fix+ nodules led to the death of intracellular rhizobia and associated with co-stimulation of defense and senescence markers, indicating that in fix+ nodules the relationship between the two processes switches from opposite to synergistic to control symbiont survival during response to the stress. Our data show that the immune response in stressed WT nodules is linked to the repression of DEFECTIVE IN NITROGEN FIXATION 2 (DNF2), Symbiotic CYSTEINE-RICH RECEPTOR-LIKE KINASE (SymCRK), and REGULATOR OF SYMBIOSOME DIFFERENTIATION (RSD), key genes involved in symbiotic immunity suppression. This study provides insight to understand the links between senescence and immunity in Medicago nodules.
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Affiliation(s)
- Fathi Berrabah
- Faculty of Sciences, Department of Biology, Amar Telidji University, 03000 Laghouat, Algeria
- Research Unit of Medicinal Plants (RUMP), National Center of Biotechnology Research, CRBt, 25000 Constantine, Algeria
| | - Gautier Bernal
- Université Paris-Saclay, CNRS, INRAE, Université d’Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
- Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Ait-Salem Elhosseyn
- Université Paris-Saclay, CNRS, INRAE, Université d’Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
- Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Cyrille El Kassis
- Université Paris-Saclay, CNRS, INRAE, Université d’Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
- Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Roxane L’Horset
- Pôle de Protection des Plantes, UMR PVBMT, 97410 Saint-Pierre, Réunion, France
| | - Farouk Benaceur
- Faculty of Sciences, Department of Biology, Amar Telidji University, 03000 Laghouat, Algeria
- Research Unit of Medicinal Plants (RUMP), National Center of Biotechnology Research, CRBt, 25000 Constantine, Algeria
| | - Jiangqi Wen
- The Institute of Agricultural Biosciences, Oklahoma State University, Ardmore, Oklahoma 73401, USA
| | - Kirankumar S Mysore
- The Institute of Agricultural Biosciences, Oklahoma State University, Ardmore, Oklahoma 73401, USA
| | - Marie Garmier
- Université Paris-Saclay, CNRS, INRAE, Université d’Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
- Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Benjamin Gourion
- LIPME, Université de Toulouse, INRAE, CNRS, 31320 Castanet-Tolosan, France
| | - Pascal Ratet
- Université Paris-Saclay, CNRS, INRAE, Université d’Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
- Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
| | - Véronique Gruber
- Université Paris-Saclay, CNRS, INRAE, Université d’Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
- Université Paris Cité, Institute of Plant Sciences Paris-Saclay (IPS2), 91190 Gif-sur-Yvette, France
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21
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Li Y, Yu H, Liu L, Liu Y, Huang L, Tan H. Transcriptomic and physiological analyses unravel the effect and mechanism of halosulfuron-methyl on the symbiosis between rhizobium and soybean. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 247:114248. [PMID: 36332406 DOI: 10.1016/j.ecoenv.2022.114248] [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: 04/22/2022] [Revised: 10/24/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
Halosulfuron-methyl (HSM) is a new and highly effective sulfonylurea herbicide widely used in weed control, but its residue in the environment poses a potential risk to soybean. Soybean-rhizobium symbiotic nitrogen fixation is crucial for sustainable agricultural development and ecological environment health. However, the impact of HSM on the symbiosis between soybean and rhizobium is unclear. In this study, the effects of HSM on the soybean-rhizobium symbiotic process and nitrogen fixation were investigated by means of transcriptomic and physiological analyses. Treatment with a concentration of HSM less than 0.5 mg L-1 had no effect on rhizobium growth, but significantly reduced nodules number, the biomass of soybean nodules, and nitrogenase activity in root nodules (P < 0.05). Transcriptomic analysis showed that differentially expressed genes (DEGs) involved in NH4+ assimilation were significantly downregulated (P < 0.05). In addition, the activities of NH4+ assimilation enzymes were markedly reduced. This result was further confirmed by the accumulation of NH4+ in root nodules, indicating that the inhibition of nitrogen fixation by HSM may be caused by excessive NH4+ accumulation in root nodules. Furthermore, DEGs involved in flavonoid synthesis, phytohormone biosynthesis, and phytohormone signaling transduction were significantly downregulated (P < 0.05), which was consistent with the decrease in flavonoid and phytohormone contents determined in this study. These results suggested that HSM may inhibit soybean nodulation by inhibiting flavonoid synthesis in soybean roots, disrupting the balance of plant endogenous hormones in roots during symbiosis, and blocking the transmission of hormone signals during the symbiosis. Our findings provide new insights into the effects of HSM on the legume-rhizobium nodule symbiotic process.
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Affiliation(s)
- Yuanfu Li
- Guangxi Key Laboratory for Agro-Environment and Agro, Product Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, China
| | - Huan Yu
- Guangxi Key Laboratory for Agro-Environment and Agro, Product Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, China
| | - Li Liu
- Guangxi Key Laboratory for Agro-Environment and Agro, Product Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, China
| | - Yanmei Liu
- Guangxi Key Laboratory for Agro-Environment and Agro, Product Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, China
| | - Lulu Huang
- Guangxi Key Laboratory for Agro-Environment and Agro, Product Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, China
| | - Huihua Tan
- Guangxi Key Laboratory for Agro-Environment and Agro, Product Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, China.
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22
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Zorin EA, Kliukova MS, Afonin AM, Gribchenko ES, Gordon ML, Sulima AS, Zhernakov AI, Kulaeva OA, Romanyuk DA, Kusakin PG, Tsyganova AV, Tsyganov VE, Tikhonovich IA, Zhukov VA. A variable gene family encoding nodule-specific cysteine-rich peptides in pea ( Pisum sativum L.). FRONTIERS IN PLANT SCIENCE 2022; 13:884726. [PMID: 36186063 PMCID: PMC9515463 DOI: 10.3389/fpls.2022.884726] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 08/08/2022] [Indexed: 06/16/2023]
Abstract
Various legume plants form root nodules in which symbiotic bacteria (rhizobia) fix atmospheric nitrogen after differentiation into a symbiotic form named bacteroids. In some legume species, bacteroid differentiation is promoted by defensin-like nodule-specific cysteine-rich (NCR) peptides. NCR peptides have best been studied in the model legume Medicago truncatula Gaertn., while in many other legumes relevant information is still fragmentary. Here, we characterize the NCR gene family in pea (Pisum sativum L.) using genomic and transcriptomic data. We found 360 genes encoding NCR peptides that are expressed in nodules. The sequences of pea NCR genes and putative peptides are highly variable and differ significantly from NCR sequences of M. truncatula. Indeed, only one pair of orthologs (PsNCR47-MtNCR312) has been identified. The NCR genes in the pea genome are located in clusters, and the expression patterns of NCR genes from one cluster tend to be similar. These data support the idea of independent evolution of NCR genes by duplication and diversification in related legume species. We also described spatiotemporal expression profiles of NCRs and identified specific transcription factor (TF) binding sites in promoters of "early" and "late" NCR genes. Further, we studied the expression of NCR genes in nodules of Fix- mutants and predicted potential regulators of NCR gene expression, one among them being the TF ERN1 involved in the early steps of nodule organogenesis. In general, this study contributes to understanding the functions of NCRs in legume nodules and contributes to understanding the diversity and potential antibiotic properties of pea nodule-specific antimicrobial molecules.
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Affiliation(s)
- Evgeny A. Zorin
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Marina S. Kliukova
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Alexey M. Afonin
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Emma S. Gribchenko
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Mikhail L. Gordon
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Anton S. Sulima
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | | | - Olga A. Kulaeva
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Daria A. Romanyuk
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Pyotr G. Kusakin
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Anna V. Tsyganova
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Viktor E. Tsyganov
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Igor A. Tikhonovich
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
- Department of Genetics and Biotechnology, Faculty of Biology, Saint Petersburg State University, Saint Petersburg, Russia
| | - Vladimir A. Zhukov
- All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
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23
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Sankari S, Babu VM, Bian K, Alhhazmi A, Andorfer MC, Avalos DM, Smith TA, Yoon K, Drennan CL, Yaffe MB, Lourido S, Walker GC. A haem-sequestering plant peptide promotes iron uptake in symbiotic bacteria. Nat Microbiol 2022; 7:1453-1465. [PMID: 35953657 PMCID: PMC9420810 DOI: 10.1038/s41564-022-01192-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 06/29/2022] [Indexed: 11/09/2022]
Abstract
Symbiotic partnerships with rhizobial bacteria enable legumes to grow without nitrogen fertilizer because rhizobia convert atmospheric nitrogen gas into ammonia via nitrogenase. After Sinorhizobium meliloti penetrate the root nodules that they have elicited in Medicago truncatula, the plant produces a family of about 700 nodule cysteine-rich (NCR) peptides that guide the differentiation of endocytosed bacteria into nitrogen-fixing bacteroids. The sequences of the NCR peptides are related to the defensin class of antimicrobial peptides, but have been adapted to play symbiotic roles. Using a variety of spectroscopic, biophysical and biochemical techniques, we show here that the most extensively characterized NCR peptide, 24 amino acid NCR247, binds haem with nanomolar affinity. Bound haem molecules and their iron are initially made biologically inaccessible through the formation of hexamers (6 haem/6 NCR247) and then higher-order complexes. We present evidence that NCR247 is crucial for effective nitrogen-fixing symbiosis. We propose that by sequestering haem and its bound iron, NCR247 creates a physiological state of haem deprivation. This in turn induces an iron-starvation response in rhizobia that results in iron import, which itself is required for nitrogenase activity. Using the same methods as for L-NCR247, we show that the D-enantiomer of NCR247 can bind and sequester haem in an equivalent manner. The special abilities of NCR247 and its D-enantiomer to sequester haem suggest a broad range of potential applications related to human health.
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Affiliation(s)
- Siva Sankari
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Vignesh M.P. Babu
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Ke Bian
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Areej Alhhazmi
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Mary C. Andorfer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Dante M. Avalos
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Harvard Graduate Program in Biophysics, Harvard University, Cambridge, MA 02138, USA
| | - Tyler A. Smith
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Kwan Yoon
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Catherine L. Drennan
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Michael B. Yaffe
- Departments of Biology and Biological Engineering, and Center for Precision Cancer Medicine, David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute for Technology, Cambridge, MA 02139, USA.,Divisions of Acute Care Surgery, Trauma, and Surgical Critical Care, and Surgical Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215 USA
| | - Sebastian Lourido
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Graham C. Walker
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
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24
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Jardinaud MF, Fromentin J, Auriac MC, Moreau S, Pecrix Y, Taconnat L, Cottret L, Aubert G, Balzergue S, Burstin J, Carrere S, Gamas P. MtEFD and MtEFD2: Two transcription factors with distinct neofunctionalization in symbiotic nodule development. PLANT PHYSIOLOGY 2022; 189:1587-1607. [PMID: 35471237 PMCID: PMC9237690 DOI: 10.1093/plphys/kiac177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/21/2022] [Indexed: 05/31/2023]
Abstract
Rhizobium-legume nitrogen-fixing symbiosis involves the formation of a specific organ, the root nodule, which provides bacteria with the proper cellular environment for atmospheric nitrogen fixation. Coordinated differentiation of plant and bacterial cells is an essential step of nodule development, for which few transcriptional regulators have been characterized. Medicago truncatula ETHYLENE RESPONSE FACTOR REQUIRED FOR NODULE DIFFERENTIATION (MtEFD) encodes an APETALA2/ETHYLENE RESPONSIVE FACTOR (ERF) transcription factor, the mutation of which leads to both hypernodulation and severe defects in nodule development. MtEFD positively controls a negative regulator of cytokinin signaling, the RESPONSE REGULATOR 4 (MtRR4) gene. Here we showed that that the Mtefd-1 mutation affects both plant and bacterial endoreduplication in nodules, as well as the expression of hundreds of genes in young and mature nodules, upstream of known regulators of symbiotic differentiation. MtRR4 expressed with the MtEFD promoter complemented Mtefd-1 hypernodulation but not the nodule differentiation phenotype. Unexpectedly, a nonlegume homolog of MtEFD, AtERF003 in Arabidopsis (Arabidopsis thaliana), could efficiently complement both phenotypes of Mtefd-1, in contrast to the MtEFD paralog MtEFD2 expressed in the root and nodule meristematic zone. A domain swap experiment showed that MtEFD2 differs from MtEFD by its C-terminal fraction outside the DNA binding domain. Furthermore, clustered regularly interspaced short palindromic repeats-CRISPR associated protein 9 (CRISPR-Cas9) mutagenesis of MtEFD2 led to a reduction in the number of nodules formed in Mtefd-1, with downregulation of a set of genes, including notably NUCLEAR FACTOR-YA1 (MtNF-YA1) and MtNF-YB16, which are essential for nodule meristem establishment. We, therefore, conclude that nitrogen-fixing symbiosis recruited two proteins originally expressed in roots, MtEFD and MtEFD2, with distinct functions and neofunctionalization processes for each of them.
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Affiliation(s)
| | | | | | - Sandra Moreau
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | | | | | - Ludovic Cottret
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - Grégoire Aubert
- Agroécologie, AgroSup Dijon, INRAE, Université Bourgogne Franche-Comté, Dijon, France
| | | | - Judith Burstin
- Agroécologie, AgroSup Dijon, INRAE, Université Bourgogne Franche-Comté, Dijon, France
| | - Sébastien Carrere
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
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25
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Zhang Y, Gallant É, Park JD, Seyedsayamdost MR. The Small-Molecule Language of Dynamic Microbial Interactions. Annu Rev Microbiol 2022; 76:641-660. [PMID: 35679616 PMCID: PMC10171915 DOI: 10.1146/annurev-micro-042722-091052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although microbes are routinely grown in monocultures in the laboratory, they are almost never encountered as single species in the wild. Our ability to detect and identify new microorganisms has advanced significantly in recent years, but our understanding of the mechanisms that mediate microbial interactions has lagged behind. What makes this task more challenging is that microbial alliances can be dynamic, consisting of multiple phases. The transitions between phases, and the interactions in general, are often mediated by a chemical language consisting of small molecules, also referred to as secondary metabolites or natural products. In this microbial lexicon, the molecules are like words and through their effects on recipient cells they convey meaning. The current review highlights three dynamic microbial interactions in which some of the words and their meanings have been characterized, especially those that mediate transitions in selected multiphasic associations. These systems provide insights into the principles that govern microbial symbioses and a playbook for interrogating similar associations in diverse ecological niches. Expected final online publication date for the Annual Review of Microbiology, Volume 76 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Yifan Zhang
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA; ,
| | - Étienne Gallant
- Department of Chemistry, Princeton University, Princeton, New Jersey, USA; ,
| | - Jong-Duk Park
- Department of Chemistry, Princeton University, Princeton, New Jersey, USA; ,
| | - Mohammad R Seyedsayamdost
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA; , .,Department of Chemistry, Princeton University, Princeton, New Jersey, USA; ,
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26
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Huang R, Snedden WA, diCenzo GC. Reference nodule transcriptomes for Melilotus officinalis and Medicago sativa cv. Algonquin. PLANT DIRECT 2022; 6:e408. [PMID: 35774624 PMCID: PMC9219011 DOI: 10.1002/pld3.408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 05/14/2022] [Accepted: 05/19/2022] [Indexed: 05/10/2023]
Abstract
Host/symbiont compatibility is a hallmark of the symbiotic nitrogen-fixing interaction between rhizobia and legumes, mediated in part by plant-produced nodule-specific cysteine-rich (NCR) peptides and the bacterial BacA membrane protein that can act as a NCR peptide transporter. In addition, the genetic and metabolic properties supporting symbiotic nitrogen fixation often differ between compatible partners, including those sharing a common partner, highlighting the need for multiple study systems. Here, we report high-quality nodule transcriptome assemblies for Medicago sativa cv. Algonquin and Melilotus officinalis, two legumes able to form compatible symbioses with Sinorhizobium meliloti. The compressed M. sativa and M. officinalis assemblies consisted of 79,978 and 64,593 contigs, respectively, of which 33,341 and 28,278 were assigned putative annotations, respectively. As expected, the two transcriptomes showed broad similarity at a global level. We were particularly interested in the NCR peptide profiles of these plants, as these peptides drive bacterial differentiation during the symbiosis. A total of 412 and 308 NCR peptides were predicted from the M. sativa and M. officinalis transcriptomes, respectively, with approximately 9% of the transcriptome of both species consisting of NCR transcripts. Notably, transcripts encoding highly cationic NCR peptides (isoelectric point > 9.5), which are known to have antimicrobial properties, were ∼2-fold more abundant in M. sativa than in M. officinalis, and ∼27-fold more abundant when considering only NCR peptides in the six-cysteine class. We hypothesize that the difference in abundance of highly cationic NCR peptides explains our previous observation that some rhizobial bacA alleles which can support symbiosis with M. officinalis are unable to support symbiosis with M. sativa.
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Affiliation(s)
- Rui Huang
- Department of BiologyQueen's UniversityKingstonOntarioCanada
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27
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Improved and Highly Efficient Agrobacterium rhizogenes-Mediated Genetic Transformation Protocol: Efficient Tools for Functional Analysis of Root-Specific Resistance Genes for Solanum lycopersicum cv. Micro-Tom. SUSTAINABILITY 2022. [DOI: 10.3390/su14116525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Gene function analysis, molecular breeding, and the introduction of new traits in crop plants all require the development of a high-performance genetic transformation system. In numerous crops, including tomatoes, Agrobacterium-mediated genetic transformation is the preferred method. As one of our ongoing research efforts, we are in the process of mapping a broad-spectrum nematode resistance gene (Me1) in pepper. We work to transform tomato plants with candidate genes to confer resistance to nematodes in Solanaceae members. The transformation technology development is designed to produce a reproducible, rapid, and highly effective Agrobacterium-mediated genetic transformation system of Micro-Tom. In our system, a transformation efficiency of over 90% was achieved. The entire procedure, starting from the germination of seeds to the establishment of transformed plants in soil, was completed in 53 days. We confirmed the presence of the NeoR/KanR and DsRed genes in the transformed roots by polymerase chain reaction. The hairy root plants were infected with nematodes, and after 3 months, the presence of DsRed and NeoR/KanR genes was detected in the transformant roots to confirm the long-term effectiveness of the method. The presented study may facilitate root-related research and exploration of root–pathogen interactions.
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28
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Wendlandt CE, Roberts M, Nguyen KT, Graham ML, Lopez Z, Helliwell EE, Friesen ML, Griffitts JS, Price P, Porter SS. Negotiating mutualism: A locus for exploitation by rhizobia has a broad effect size distribution and context-dependent effects on legume hosts. J Evol Biol 2022; 35:844-854. [PMID: 35506571 PMCID: PMC9325427 DOI: 10.1111/jeb.14011] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 03/07/2022] [Accepted: 04/02/2022] [Indexed: 01/02/2023]
Abstract
In mutualisms, variation at genes determining partner fitness provides the raw material upon which coevolutionary selection acts, setting the dynamics and pace of coevolution. However, we know little about variation in the effects of genes that underlie symbiotic fitness in natural mutualist populations. In some species of legumes that form root nodule symbioses with nitrogen‐fixing rhizobial bacteria, hosts secrete nodule‐specific cysteine‐rich (NCR) peptides that cause rhizobia to differentiate in the nodule environment. However, rhizobia can cleave NCR peptides through the expression of genes like the plasmid‐borne Host range restriction peptidase (hrrP), whose product degrades specific NCR peptides. Although hrrP activity can confer host exploitation by depressing host fitness and enhancing symbiont fitness, the effects of hrrP on symbiosis phenotypes depend strongly on the genotypes of the interacting partners. However, the effects of hrrP have yet to be characterised in a natural population context, so its contribution to variation in wild mutualist populations is unknown. To understand the distribution of effects of hrrP in wild rhizobia, we measured mutualism phenotypes conferred by hrrP in 12 wild Ensifer medicae strains. To evaluate context dependency of hrrP effects, we compared hrrP effects across two Medicago polymorpha host genotypes and across two experimental years for five E. medicae strains. We show for the first time in a natural population context that hrrP has a wide distribution of effect sizes for many mutualism traits, ranging from strongly positive to strongly negative. Furthermore, we show that hrrP effect size varies across host genotypes and experiment years, suggesting that researchers should be cautious about extrapolating the role of genes in natural populations from controlled laboratory studies of single genetic variants.
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Affiliation(s)
- Camille E Wendlandt
- School of Biological Sciences, Washington State University, Vancouver, Washington, USA
| | - Miles Roberts
- School of Biological Sciences, Washington State University, Vancouver, Washington, USA
| | - Kyle T Nguyen
- School of Biological Sciences, Washington State University, Vancouver, Washington, USA
| | - Marion L Graham
- Biology Department, Eastern Michigan University, Ypsilanti, Michigan, USA
| | - Zoie Lopez
- School of Biological Sciences, Washington State University, Vancouver, Washington, USA
| | - Emily E Helliwell
- School of Biological Sciences, Washington State University, Vancouver, Washington, USA
| | - Maren L Friesen
- Department of Plant Pathology, Washington State University, Pullman, Washington, USA.,Department of Crop & Soil Sciences, Washington State University, Pullman, Washington, USA
| | - Joel S Griffitts
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, USA
| | - Paul Price
- Biology Department, Eastern Michigan University, Ypsilanti, Michigan, USA
| | - Stephanie S Porter
- School of Biological Sciences, Washington State University, Vancouver, Washington, USA
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29
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Fan W, Xia C, Wang S, Liu J, Deng L, Sun S, Wang X. Rhizobial infection of 4C cells triggers their endoreduplication during symbiotic nodule development in soybean. THE NEW PHYTOLOGIST 2022; 234:1018-1030. [PMID: 35175637 DOI: 10.1111/nph.18036] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
Symbiosis between legumes and rhizobia results in the formation of nitrogen-fixing root nodules. Endoreduplication is essential for nodule development and efficient nitrogen fixation; however, the cellular mechanism by which rhizobial infection causes endoreduplication in symbiotic nodules and the roles of the resulting polyploid cells in nitrogen fixation remain largely unknown. Here, we developed a series of different approaches to separate infected cells (ICs) and uninfected cells (UCs) and determined their ploidy levels in soybean (Glycine max) developing nodules. We demonstrated that 4C nuclei exist in both UCs and ICs of developing nodules and that these 4C cells are primarily invaded by rhizobia and subsequently undergo endoreduplication. Furthermore, RNA-sequencing analysis of nuclei with different ploidy levels from soybean nodules at 12 d post-infection (dpi) and 20 dpi showed that 4C cells are predominantly ICs in 12-dpi nodules but UCs in 20-dpi nodules. We conclude that the infection of 4C cells by rhizobia is critical for initiating endoreduplication. These findings provide significant insight into rhizobial infection, nodule endoreduplication and nitrogen fixation in symbiotic nodules.
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Affiliation(s)
- Wei Fan
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475004, China
| | - Chunjiao Xia
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shixiang Wang
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jing Liu
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475004, China
| | - Lijun Deng
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475004, China
| | - Shiyong Sun
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475004, China
| | - Xuelu Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475004, China
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30
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Wang D, Dong W, Murray J, Wang E. Innovation and appropriation in mycorrhizal and rhizobial Symbioses. THE PLANT CELL 2022; 34:1573-1599. [PMID: 35157080 PMCID: PMC9048890 DOI: 10.1093/plcell/koac039] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 01/21/2022] [Indexed: 05/20/2023]
Abstract
Most land plants benefit from endosymbiotic interactions with mycorrhizal fungi, including legumes and some nonlegumes that also interact with endosymbiotic nitrogen (N)-fixing bacteria to form nodules. In addition to these helpful interactions, plants are continuously exposed to would-be pathogenic microbes: discriminating between friends and foes is a major determinant of plant survival. Recent breakthroughs have revealed how some key signals from pathogens and symbionts are distinguished. Once this checkpoint has been passed and a compatible symbiont is recognized, the plant coordinates the sequential development of two types of specialized structures in the host. The first serves to mediate infection, and the second, which appears later, serves as sophisticated intracellular nutrient exchange interfaces. The overlap in both the signaling pathways and downstream infection components of these symbioses reflects their evolutionary relatedness and the common requirements of these two interactions. However, the different outputs of the symbioses, phosphate uptake versus N fixation, require fundamentally different components and physical environments and necessitated the recruitment of different master regulators, NODULE INCEPTION-LIKE PROTEINS, and PHOSPHATE STARVATION RESPONSES, for nodulation and mycorrhization, respectively.
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Affiliation(s)
- Dapeng Wang
- National Key Laboratory of Plant Molecular Genetics, Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Wentao Dong
- National Key Laboratory of Plant Molecular Genetics, Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | | | - Ertao Wang
- Authors for correspondence: (E.W) and (J.M.)
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31
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Wang T, Balla B, Kovács S, Kereszt A. Varietas Delectat: Exploring Natural Variations in Nitrogen-Fixing Symbiosis Research. FRONTIERS IN PLANT SCIENCE 2022; 13:856187. [PMID: 35481136 PMCID: PMC9037385 DOI: 10.3389/fpls.2022.856187] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
The nitrogen-fixing symbiosis between leguminous plants and soil bacteria collectively called rhizobia plays an important role in the global nitrogen cycle and is an essential component of sustainable agriculture. Genetic determinants directing the development and functioning of the interaction have been identified with the help of a very limited number of model plants and bacterial strains. Most of the information obtained from the study of model systems could be validated on crop plants and their partners. The investigation of soybean cultivars and different rhizobia, however, has revealed the existence of ineffective interactions between otherwise effective partners that resemble gene-for-gene interactions described for pathogenic systems. Since then, incompatible interactions between natural isolates of model plants, called ecotypes, and different bacterial partner strains have been reported. Moreover, diverse phenotypes of both bacterial mutants on different host plants and plant mutants with different bacterial strains have been described. Identification of the genetic factors behind the phenotypic differences did already and will reveal novel functions of known genes/proteins, the role of certain proteins in some interactions, and the fine regulation of the steps during nodule development.
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Affiliation(s)
- Ting Wang
- Eötvös Loránd Research Network, Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
- Doctoral School in Biology, University of Szeged, Szeged, Hungary
| | - Benedikta Balla
- Eötvös Loránd Research Network, Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
- Doctoral School in Biology, University of Szeged, Szeged, Hungary
| | - Szilárd Kovács
- Eötvös Loránd Research Network, Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
| | - Attila Kereszt
- Eötvös Loránd Research Network, Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
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32
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Cangioli L, Vaccaro F, Fini M, Mengoni A, Fagorzi C. Scent of a Symbiont: The Personalized Genetic Relationships of Rhizobium—Plant Interaction. Int J Mol Sci 2022; 23:ijms23063358. [PMID: 35328782 PMCID: PMC8954435 DOI: 10.3390/ijms23063358] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 01/24/2023] Open
Abstract
Many molecular signals are exchanged between rhizobia and host legume plants, some of which are crucial for symbiosis to take place, while others are modifiers of the interaction, which have great importance in the competition with the soil microbiota and in the genotype-specific perception of host plants. Here, we review recent findings on strain-specific and host genotype-specific interactions between rhizobia and legumes, discussing the molecular actors (genes, gene products and metabolites) which play a role in the establishment of symbiosis, and highlighting the need for research including the other components of the soil (micro)biota, which could be crucial in developing rational-based strategies for bioinoculants and synthetic communities’ assemblage.
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33
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Li A, Liu A, Wu S, Qu K, Hu H, Yang J, Shrestha N, Liu J, Ren G. Comparison of structural variants in the whole genome sequences of two Medicago truncatula ecotypes: Jemalong A17 and R108. BMC PLANT BIOLOGY 2022; 22:77. [PMID: 35193491 PMCID: PMC8862580 DOI: 10.1186/s12870-022-03469-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Structural variants (SVs) constitute a large proportion of the genomic variation that results in phenotypic variation in plants. However, they are still a largely unexplored feature in most plant genomes. Here, we present the whole-genome landscape of SVs between two model legume Medicago truncatula ecotypes-Jemalong A17 and R108- that have been extensively used in various legume biology studies. RESULTS To catalogue SVs, we first resolved the previously published R108 genome assembly (R108 v1.0) to chromosome-scale using 124 × Hi-C data, resulting in a high-quality genome assembly. The inter-chromosomal reciprocal translocations between chromosomes 4 and 8 were confirmed by performing syntenic analysis between the two genomes. Combined with the Hi-C data, it appears that these translocation events had a significant effect on chromatin organization. Using both whole-genome and short-read alignments, we identified the genomic landscape of SVs between the two genomes, some of which may account for several phenotypic differences, including their differential responses to aluminum toxicity and iron deficiency, and the development of different anthocyanin leaf markings. We also found extensive SVs within the nodule-specific cysteine-rich gene family which encodes antimicrobial peptides essential for terminal bacteroid differentiation during nitrogen-fixing symbiosis. CONCLUSIONS Our results provide a near-complete R108 genome assembly and the first genomic landscape of SVs obtained by comparing two M. truncatula ecotypes. This may provide valuable genomic resources for the functional and molecular research of legume biology in the future.
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Affiliation(s)
- Ao Li
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
| | - Ai Liu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
| | - Shuang Wu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
| | - Kunjing Qu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
| | - Hongyin Hu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
| | - Jinli Yang
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
| | - Nawal Shrestha
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
| | - Jianquan Liu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Lab of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, China
| | - Guangpeng Ren
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, China.
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34
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DNA Methylation in
Ensifer
Species during Free-Living Growth and during Nitrogen-Fixing Symbiosis with
Medicago
spp. mSystems 2022; 7:e0109221. [PMID: 35089065 PMCID: PMC8725594 DOI: 10.1128/msystems.01092-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Nitrogen fixation by rhizobia in symbiosis with legumes is economically and ecologically important. The symbiosis can involve a complex bacterial transformation—terminal differentiation—that includes major shifts in the transcriptome and cell cycle.
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Hawkins JP, Oresnik IJ. The Rhizobium-Legume Symbiosis: Co-opting Successful Stress Management. FRONTIERS IN PLANT SCIENCE 2022; 12:796045. [PMID: 35046982 PMCID: PMC8761673 DOI: 10.3389/fpls.2021.796045] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 12/02/2021] [Indexed: 05/20/2023]
Abstract
The interaction of bacteria with plants can result in either a positive, negative, or neutral association. The rhizobium-legume interaction is a well-studied model system of a process that is considered a positive interaction. This process has evolved to require a complex signal exchange between the host and the symbiont. During this process, rhizobia are subject to several stresses, including low pH, oxidative stress, osmotic stress, as well as growth inhibiting plant peptides. A great deal of work has been carried out to characterize the bacterial response to these stresses. Many of the responses to stress are also observed to have key roles in symbiotic signaling. We propose that stress tolerance responses have been co-opted by the plant and bacterial partners to play a role in the complex signal exchange that occurs between rhizobia and legumes to establish functional symbiosis. This review will cover how rhizobia tolerate stresses, and how aspects of these tolerance mechanisms play a role in signal exchange between rhizobia and legumes.
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Affiliation(s)
| | - Ivan J. Oresnik
- Department of Microbiology, University of Manitoba, Winnipeg, MB, Canada
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36
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Rainwater R, Mukherjee A. The legume-rhizobia symbiosis can be supported on Mars soil simulants. PLoS One 2021; 16:e0259957. [PMID: 34879082 PMCID: PMC8654199 DOI: 10.1371/journal.pone.0259957] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 10/30/2021] [Indexed: 11/20/2022] Open
Abstract
Legumes (soybeans, peas, lentils, etc.) play important roles in agriculture on Earth because of their food value and their ability to form a mutualistic beneficial association with rhizobia bacteria. In this association, the host plant benefits from atmospheric nitrogen fixation by rhizobia. The presence of nitrogen in the Mars atmosphere offers the possibility to take advantage of this important plant-microbe association. While some studies have shown that Mars soil simulants can support plant growth, none have investigated if these soils can support the legume-rhizobia symbiosis. In this study, we investigated the establishment of the legume-rhizobia symbiosis on different Mars soil simulants (different grades of the Mojave Mars Simulant (MMS)-1: Coarse, Fine, Unsorted, Superfine, and the MMS-2 simulant). We used the model legume, Medicago truncatula, and its symbiotic partners, Sinorhizobium meliloti and Sinorhizobium medicae, in these experiments. Our results show that root nodules could develop on M. truncatula roots when grown on these Mars soil simulants and were comparable to those formed on plants that were grown on sand. We also detected nifH (a reporter gene for nitrogen fixation) expression inside these nodules. Our results indicate that the different Mars soil simulants used in this study can support legume-rhizobia symbiosis. While the average number of lateral roots and nodule numbers were comparable on plants grown on the different soil simulants, total plant mass was higher in plants grown on MMS-2 soil than on MMS-1 soil and its variants. Our results imply that the chemical composition of the simulants is more critical than their grain size for plant mass. Based on these results, we recommend that the MMS-2 Superfine soil simulant is a better fit than the MMS-1 soil and it’s variants for future studies. Our findings can serve as an excellent resource for future studies investigating beneficial plant-microbe associations for sustainable agriculture on Mars.
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Affiliation(s)
- Randall Rainwater
- Department of Biology, University of Central Arkansas, Conway, AR, United States of America
| | - Arijit Mukherjee
- Department of Biology, University of Central Arkansas, Conway, AR, United States of America
- * E-mail:
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37
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Pirhanov GG. Sinorhizobium meliloti AS A PERSPECTIVE OBJECT FOR MODERN BIOTECHNOLOGY. BIOTECHNOLOGIA ACTA 2021. [DOI: 10.15407/biotech14.06.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Sinorhizobium meliloti is a Gram-negative soil nitrogen-fixing bacterium that increases the yield of legumes. There is information in the literature about the complete genome sequence of this bacterium, in addition, the polysaccharide composition of the biofilm, which is actively involved in nitrogen fixation, has been studied. The well-known nucleotide sequence, as well as the genetic and biochemical features of S. meliloti make this organism an ideal model for biotechnological research. The purpose of this work was to analyze the current data provided in the literature on the symbiotic interaction of Sinorhizobium meliloti with the host plant, and to characterize the main directions of the use of this bacterium in agriculture, bioremediation and medicine.
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38
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Sinorhizobium meliloti Functions Required for Resistance to Antimicrobial NCR Peptides and Bacteroid Differentiation. mBio 2021; 12:e0089521. [PMID: 34311575 PMCID: PMC8406287 DOI: 10.1128/mbio.00895-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Legumes of the Medicago genus have a symbiotic relationship with the bacterium Sinorhizobium meliloti and develop root nodules housing large numbers of intracellular symbionts. Members of the nodule-specific cysteine-rich peptide (NCR) family induce the endosymbionts into a terminal differentiated state. Individual cationic NCRs are antimicrobial peptides that have the capacity to kill the symbiont, but the nodule cell environment prevents killing. Moreover, the bacterial broad-specificity peptide uptake transporter BacA and exopolysaccharides contribute to protect the endosymbionts against the toxic activity of NCRs. Here, we show that other S. meliloti functions participate in the protection of the endosymbionts; these include an additional broad-specificity peptide uptake transporter encoded by the yejABEF genes and lipopolysaccharide modifications mediated by lpsB and lpxXL, as well as rpoH1, encoding a stress sigma factor. Strains with mutations in these genes show a strain-specific increased sensitivity profile against a panel of NCRs and form nodules in which bacteroid differentiation is affected. The lpsB mutant nodule bacteria do not differentiate, the lpxXL and rpoH1 mutants form some seemingly fully differentiated bacteroids, although most of the nodule bacteria are undifferentiated, while the yejABEF mutants form hypertrophied but nitrogen-fixing bacteroids. The nodule bacteria of all the mutants have a strongly enhanced membrane permeability, which is dependent on the transport of NCRs to the endosymbionts. Our results suggest that S. meliloti relies on a suite of functions, including peptide transporters, the bacterial envelope structures, and stress response regulators, to resist the aggressive assault of NCR peptides in the nodule cells. IMPORTANCE The nitrogen-fixing symbiosis of legumes with rhizobium bacteria has a predominant ecological role in the nitrogen cycle and has the potential to provide the nitrogen required for plant growth in agriculture. The host plants allow the rhizobia to colonize specific symbiotic organs, the nodules, in large numbers in order to produce sufficient reduced nitrogen for the plants' needs. Some legumes, including Medicago spp., produce massively antimicrobial peptides to keep this large bacterial population in check. These peptides, known as NCRs, have the potential to kill the rhizobia, but in nodules, they rather inhibit the division of the bacteria, which maintain a high nitrogen-fixing activity. In this study, we show that the tempering of the antimicrobial activity of the NCR peptides in the Medicago symbiont Sinorhizobium meliloti is multifactorial and requires the YejABEF peptide transporter, the lipopolysaccharide outer membrane, and the stress response regulator RpoH1.
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A conserved rhizobial peptidase that interacts with host-derived symbiotic peptides. Sci Rep 2021; 11:11779. [PMID: 34083727 PMCID: PMC8175422 DOI: 10.1038/s41598-021-91394-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 05/24/2021] [Indexed: 02/07/2023] Open
Abstract
In the Medicago truncatula-Sinorhizobium meliloti symbiosis, chemical signaling initiates rhizobial infection of root nodule tissue, where a large portion of the bacteria are endocytosed into root nodule cells to function in nitrogen-fixing organelles. These intracellular bacteria are subjected to an arsenal of plant-derived nodule-specific cysteine-rich (NCR) peptides, which induce the physiological changes that accompany nitrogen fixation. NCR peptides drive these intracellular bacteria toward terminal differentiation. The bacterial peptidase HrrP was previously shown to degrade host-derived NCR peptides and give the bacterial symbionts greater fitness at the expense of host fitness. The hrrP gene is found in roughly 10% of Sinorhizobium isolates, as it is carried on an accessory plasmid. The objective of the present study is to identify peptidase genes in the core genome of S. meliloti that modulate symbiotic outcome in a manner similar to the accessory hrrP gene. In an overexpression screen of annotated peptidase genes, we identified one such symbiosis-associated peptidase (sap) gene, sapA (SMc00451). When overexpressed, sapA leads to a significant decrease in plant fitness. Its promoter is active in root nodules, with only weak expression evident under free-living conditions. The SapA enzyme can degrade a broad range of NCR peptides in vitro.
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40
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Hu XL, Lu H, Hassan MM, Zhang J, Yuan G, Abraham PE, Shrestha HK, Villalobos Solis MI, Chen JG, Tschaplinski TJ, Doktycz MJ, Tuskan GA, Cheng ZMM, Yang X. Advances and perspectives in discovery and functional analysis of small secreted proteins in plants. HORTICULTURE RESEARCH 2021; 8:130. [PMID: 34059650 PMCID: PMC8167165 DOI: 10.1038/s41438-021-00570-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 04/26/2021] [Indexed: 05/02/2023]
Abstract
Small secreted proteins (SSPs) are less than 250 amino acids in length and are actively transported out of cells through conventional protein secretion pathways or unconventional protein secretion pathways. In plants, SSPs have been found to play important roles in various processes, including plant growth and development, plant response to abiotic and biotic stresses, and beneficial plant-microbe interactions. Over the past 10 years, substantial progress has been made in the identification and functional characterization of SSPs in several plant species relevant to agriculture, bioenergy, and horticulture. Yet, there are potentially a lot of SSPs that have not been discovered in plant genomes, which is largely due to limitations of existing computational algorithms. Recent advances in genomics, transcriptomics, and proteomics research, as well as the development of new computational algorithms based on machine learning, provide unprecedented capabilities for genome-wide discovery of novel SSPs in plants. In this review, we summarize known SSPs and their functions in various plant species. Then we provide an update on the computational and experimental approaches that can be used to discover new SSPs. Finally, we discuss strategies for elucidating the biological functions of SSPs in plants.
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Affiliation(s)
- Xiao-Li Hu
- Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Haiwei Lu
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | | | - Jin Zhang
- State Key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, Zhejiang, China
| | - Guoliang Yuan
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Paul E Abraham
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Him K Shrestha
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA
| | | | - Jin-Gui Chen
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Timothy J Tschaplinski
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Mitchel J Doktycz
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Gerald A Tuskan
- The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Zong-Ming Max Cheng
- Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
- College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu, China.
| | - Xiaohan Yang
- Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
- The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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41
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Characteristics and Research Progress of Legume Nodule Senescence. PLANTS 2021; 10:plants10061103. [PMID: 34070891 PMCID: PMC8227080 DOI: 10.3390/plants10061103] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/28/2021] [Accepted: 05/28/2021] [Indexed: 11/17/2022]
Abstract
Delaying the nodule senescence of legume crops can prolong the time of nitrogen fixation and attenuate the lack of fertilizer in the later stage of legume crop cultivation, resulting in improved crop yield and reduced usage of nitrogen fertilizer. However, effective measures to delay the nodule senescence of legume crops in agriculture are relatively lacking. In the present review, we summarized the structural and physiological characteristics of nodule senescence, as well as the corresponding detection methods, providing technical support for the identification of nodule senescence phenotype. We then outlined the key genes currently known to be involved in the regulation of nodule senescence, offering the molecular genetic information for breeding varieties with delayed nodule senescence. In addition, we reviewed various abiotic factors affecting nodule senescence, providing a theoretical basis for the interaction between molecular genetics and abiotic factors in the regulation of nodule senescence. Finally, we briefly prospected research foci of nodule senescence in the future.
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42
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Isozumi N, Masubuchi Y, Imamura T, Mori M, Koga H, Ohki S. Structure and antimicrobial activity of NCR169, a nodule-specific cysteine-rich peptide of Medicago truncatula. Sci Rep 2021; 11:9923. [PMID: 33972675 PMCID: PMC8110993 DOI: 10.1038/s41598-021-89485-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/21/2021] [Indexed: 11/09/2022] Open
Abstract
A model legume, Medicago truncatula, has over 600 nodule-specific cysteine-rich (NCR) peptides required for symbiosis with rhizobia. Among them, NCR169, an essential factor for establishing symbiosis, has four cysteine residues that are indispensable for its function. However, knowledge of NCR169 structure and mechanism of action is still lacking. In this study, we solved two NMR structures of NCR169 caused by different disulfide linkage patterns. We show that both structures have a consensus C-terminal β-sheet attached to an extended N-terminal region with dissimilar features; one moves widely, whereas the other is relatively stapled. We further revealed that the disulfide bonds of NCR169 contribute to its structural stability and solubility. Regarding the function, one of the NCR169 oxidized forms could bind to negatively charged bacterial phospholipids. Furthermore, the positively charged lysine-rich region of NCR169 may be responsible for its antimicrobial activity against Escherichia coli and Sinorhizobium meliloti. This active region was disordered even in the phospholipid bound state, suggesting that the disordered conformation of this region is key to its function. Morphological observations suggested the mechanism of action of NCR169 on bacteria. The present study on NCR169 provides new insights into the structure and function of NCR peptides.
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Affiliation(s)
- Noriyoshi Isozumi
- Center for Nano Materials and Technology (CNMT), Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan
| | - Yuya Masubuchi
- Center for Nano Materials and Technology (CNMT), Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan
| | - Tomohiro Imamura
- Ishikawa Prefectural University, 1-308, Suematsu, Nonoichi, Ishikawa, 921-8836, Japan
| | - Masashi Mori
- Ishikawa Prefectural University, 1-308, Suematsu, Nonoichi, Ishikawa, 921-8836, Japan
| | - Hironori Koga
- Ishikawa Prefectural University, 1-308, Suematsu, Nonoichi, Ishikawa, 921-8836, Japan
| | - Shinya Ohki
- Center for Nano Materials and Technology (CNMT), Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan.
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Moore WM, Chan C, Ishikawa T, Rennie EA, Wipf HML, Benites V, Kawai-Yamada M, Mortimer JC, Scheller HV. Reprogramming sphingolipid glycosylation is required for endosymbiont persistence in Medicago truncatula. Curr Biol 2021; 31:2374-2385.e4. [PMID: 33857428 DOI: 10.1016/j.cub.2021.03.067] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/10/2020] [Accepted: 03/19/2021] [Indexed: 11/16/2022]
Abstract
Plant endosymbiosis relies on the development of specialized membranes that encapsulate the endosymbiont and facilitate nutrient exchange. However, the identity and function of lipids within these membrane interfaces is largely unknown. Here, we identify GLUCOSAMINE INOSITOL PHOSPHORYLCERAMIDE TRANSFERASE1 (GINT1) as a sphingolipid glycosyltransferase highly expressed in Medicago truncatula root nodules and roots colonized by arbuscular mycorrhizal (AM) fungi and further demonstrate that this enzyme functions in the synthesis of N-acetyl-glucosamine-decorated glycosyl inositol phosphoryl ceramides (GIPCs) in planta. MtGINT1 expression was developmentally regulated in symbiotic tissues associated with the development of symbiosome and periarbuscular membranes. RNAi silencing of MtGINT1 did not affect overall root growth but strongly impaired nodulation and AM symbiosis, resulting in the senescence of symbiosomes and arbuscules. Our results indicate that, although M. truncatula root sphingolipidome predominantly consists of hexose-decorated GIPCs, local reprogramming of GIPC glycosylation by MtGINT1 is required for the persistence of endosymbionts within the plant cell.
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Affiliation(s)
- William M Moore
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Candace Chan
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Toshiki Ishikawa
- Graduate School of Science and Engineering, Saitama University, Saitama 388-8570, Japan
| | - Emilie A Rennie
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Heidi M-L Wipf
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Veronica Benites
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Maki Kawai-Yamada
- Graduate School of Science and Engineering, Saitama University, Saitama 388-8570, Japan
| | - Jenny C Mortimer
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Henrik V Scheller
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
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Nguyen NNT, Clua J, Vetal PV, Vuarambon DJ, De Bellis D, Pervent M, Lepetit M, Udvardi M, Valentine AJ, Poirier Y. PHO1 family members transport phosphate from infected nodule cells to bacteroids in Medicago truncatula. PLANT PHYSIOLOGY 2021; 185:196-209. [PMID: 33631809 PMCID: PMC8133656 DOI: 10.1093/plphys/kiaa016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/14/2020] [Indexed: 05/20/2023]
Abstract
Legumes play an important role in the soil nitrogen availability via symbiotic nitrogen fixation (SNF). Phosphate (Pi) deficiency severely impacts SNF because of the high Pi requirement of symbiosis. Whereas PHT1 transporters are involved in Pi uptake into nodules, it is unknown how Pi is transferred from the plant infected cells to nitrogen-fixing bacteroids. We hypothesized that Medicago truncatula genes homologous to Arabidopsis PHO1, encoding a vascular apoplastic Pi exporter, are involved in Pi transfer to bacteroids. Among the seven MtPHO1 genes present in M. truncatula, we found that two genes, namely MtPHO1.1 and MtPHO1.2, were broadly expressed across the various nodule zones in addition to the root vascular system. Expressions of MtPHO1.1 and MtPHO1.2 in Nicotiana benthamiana mediated specific Pi export. Plants with nodule-specific downregulation of both MtPHO1.1 and MtPHO1.2 were generated by RNA interference (RNAi) to examine their roles in nodule Pi homeostasis. Nodules of RNAi plants had lower Pi content and a three-fold reduction in SNF, resulting in reduced shoot growth. Whereas the rate of 33Pi uptake into nodules of RNAi plants was similar to control, transfer of 33Pi from nodule cells into bacteroids was reduced and bacteroids activated their Pi-deficiency response. Our results implicate plant MtPHO1 genes in bacteroid Pi homeostasis and SNF via the transfer of Pi from nodule infected cells to bacteroids.
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Affiliation(s)
- Nga N T Nguyen
- Department of Plant Molecular Biology, Biophore Building, University of Lausanne, Lausanne 1015, Switzerland
| | - Joaquin Clua
- Department of Plant Molecular Biology, Biophore Building, University of Lausanne, Lausanne 1015, Switzerland
| | - Pallavi V Vetal
- Department of Plant Molecular Biology, Biophore Building, University of Lausanne, Lausanne 1015, Switzerland
| | - Dominique Jacques Vuarambon
- Department of Plant Molecular Biology, Biophore Building, University of Lausanne, Lausanne 1015, Switzerland
| | - Damien De Bellis
- Department of Plant Molecular Biology, Biophore Building, University of Lausanne, Lausanne 1015, Switzerland
- Electron Microscopy Facility, Biophore Building, University of Lausanne, Lausanne 1015, Switzerland
| | - Marjorie Pervent
- Laboratoire des Symbioses Tropicales et Méditerranéennes UMR 1342 INRAE-IRD-CIRAD-UM-Montpellier SupAgro, Montpellier, France
| | - Marc Lepetit
- Laboratoire des Symbioses Tropicales et Méditerranéennes UMR 1342 INRAE-IRD-CIRAD-UM-Montpellier SupAgro, Montpellier, France
| | - Michael Udvardi
- The Noble Research Institute, 2510 Sam Noble Parkway, Ardmore, OK, USA
| | - Alexander J Valentine
- Botany & Zoology Department, University of Stellenbosch, Matieland 7602, South Africa
| | - Yves Poirier
- Department of Plant Molecular Biology, Biophore Building, University of Lausanne, Lausanne 1015, Switzerland
- Author for communication:
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Peng Z, Chen H, Tan L, Shu H, Varshney RK, Zhou Z, Zhao Z, Luo Z, Chitikineni A, Wang L, Maku J, López Y, Gallo M, Zhou H, Wang J. Natural polymorphisms in a pair of NSP2 homoeologs can cause loss of nodulation in peanut. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:1104-1118. [PMID: 33130897 DOI: 10.1093/jxb/eraa505] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/27/2020] [Indexed: 06/11/2023]
Abstract
Microbial symbiosis in legumes is achieved through nitrogen-fixing root nodules, and these are important for sustainable agriculture. The molecular mechanisms underlying development of root nodules in polyploid legume crops are largely understudied. Through map-based cloning and QTL-seq approaches, we identified a pair of homoeologous GRAS transcription factor genes, Nodulation Signaling Pathway 2 (AhNSP2-B07 or Nb) and AhNSP2-A08 (Na), controlling nodulation in cultivated peanut (Arachis hypogaea L.), an allotetraploid legume crop, which exhibited non-Mendelian and Mendelian inheritance, respectively. The segregation of nodulation in the progeny of Nananbnb genotypes followed a 3:1 Mendelian ratio, in contrast to the 5:3~1:1 non-Mendelian ratio for nanaNbnb genotypes. Additionally, a much higher frequency of the nb allele (13%) than the na allele (4%) exists in the peanut germplasm collection, suggesting that Nb is less essential than Na in nodule organogenesis. Our findings reveal the genetic basis of naturally occurred non-nodulating peanut plants, which can be potentially used for nitrogen fixation improvement in peanut. Furthermore, the results have implications for and provide insights into the evolution of homoeologous genes in allopolyploid species.
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Affiliation(s)
- Ze Peng
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Huiqiong Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Lubin Tan
- Department of Plant Genetics and Breeding, China Agricultural University, Beijing, China
| | - Hongmei Shu
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Rajeev K Varshney
- Center of Excellence in Genomics and Systems Biology, International Crops Research Institute for the Semi-Arid Tropics, Patancheru, India
| | - Zhekai Zhou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Zifan Zhao
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Ziliang Luo
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Annapurna Chitikineni
- Center of Excellence in Genomics and Systems Biology, International Crops Research Institute for the Semi-Arid Tropics, Patancheru, India
| | - Liping Wang
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - James Maku
- Sciences and Mathematics Department, Glenville State College, Glenville, WV, USA
| | - Yolanda López
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Maria Gallo
- Delaware Valley University, Doylestown, PA, USA
| | - Hai Zhou
- Agronomy Department, University of Florida, Gainesville, FL, USA
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Jianping Wang
- Agronomy Department, University of Florida, Gainesville, FL, USA
- Genetics Institute, Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL, USA
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Albicoro FJ, Draghi WO, Martini MC, Salas ME, Torres Tejerizo GA, Lozano MJ, López JL, Vacca C, Cafiero JH, Pistorio M, Bednarz H, Meier D, Lagares A, Niehaus K, Becker A, Del Papa MF. The two-component system ActJK is involved in acid stress tolerance and symbiosis in Sinorhizobium meliloti. J Biotechnol 2021; 329:80-91. [PMID: 33539896 DOI: 10.1016/j.jbiotec.2021.01.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/31/2020] [Accepted: 01/08/2021] [Indexed: 01/25/2023]
Abstract
The nitrogen-fixing α-proteobacterium Sinorhizobium meliloti genome codifies at least 50 response regulator (RR) proteins mediating different and, in many cases, unknown processes. RR-mutant library screening allowed us to identify genes potentially implicated in survival to acid conditions. actJ mutation resulted in a strain with reduced growth rate under mildly acidic conditions as well as a lower capacity to tolerate a sudden shift to lethal acidic conditions compared with the parental strain. Mutation of the downstream gene actK, which encodes for a histidine kinase, showed a similar phenotype in acidic environments suggesting a functional two-component system. Interestingly, even though nodulation kinetics, quantity, and macroscopic morphology of Medicago sativa nodules were not affected in actJ and actK mutants, ActK was required to express the wild-type nitrogen fixation phenotype and ActJK was necessary for full bacteroid development and nodule occupancy. The actJK regulatory system presented here provides insights into an evolutionary process in rhizobium adaptation to acidic environments and suggests that actJK-controlled functions are crucial for optimal symbiosis development.
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Affiliation(s)
- Francisco J Albicoro
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Walter O Draghi
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - María C Martini
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - María E Salas
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - G A Torres Tejerizo
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Mauricio J Lozano
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - José L López
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Carolina Vacca
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Juan H Cafiero
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Mariano Pistorio
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Hanna Bednarz
- CeBiTec, Centrum für Biotechnologie, Universität Bielefeld, Bielefeld, Germany
| | - Doreen Meier
- CeBiTec, Centrum für Biotechnologie, Universität Bielefeld, Bielefeld, Germany; LOEWE Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany
| | - Antonio Lagares
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Karsten Niehaus
- CeBiTec, Centrum für Biotechnologie, Universität Bielefeld, Bielefeld, Germany
| | - Anke Becker
- LOEWE Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany; Faculty of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - M F Del Papa
- Instituto de Biotecnología y Biología Molecular -CONICET CCT La Plata Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina.
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Albornos L, Casado-Del-Castillo V, Martín I, Díaz-Mínguez JM, Labrador E, Dopico B. Specific tissue proteins 1 and 6 are involved in root biology during normal development and under symbiotic and pathogenic interactions in Medicago truncatula. PLANTA 2021; 253:7. [PMID: 33387090 DOI: 10.1007/s00425-020-03538-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
ST1 and ST6 are possibly involved in primary and lateral root and symbiotic nodule development, but only ST6 participates in the interaction with hemibiotrophic fungi. Specific tissue (ST) proteins have been shown to be involved in several processes related to plant nutritional status, development, and responses to biotic agents. In particular, ST1 and ST6 are mainly expressed in roots throughout plant development. Here, we analyze where and how the expression of the genes encoding both proteins are modulated in the legume model plant Medicago truncatula in response to the plant developmental program, nodulation induced by a beneficial nitrogen-fixing bacterium (Sinorhizobium meliloti) and the defense response triggered by a pathogenic hemibiotrophic fungus (Fusarium oxysporum). Gene expression results show that ST1 and ST6 participate in the vasculature development of both primary and lateral roots, although only ST6 is related to meristem activity. ST1 and ST6 clearly display different roles in the biotic interactions analyzed, where ST1 is activated in response to a N2-fixing bacterium and ST6 is up-regulated after inoculation with F. oxysporum. The role of ST1 and ST6 in the nodulation process may be related to nodule organogenesis rather than to the establishment of the interaction itself, and an increase in ST6 correlates with the activation of the salicylic acid signaling pathway during the infection and colonization processes. These results further support the role of ST6 in response to hemibiotrophic fungi. This research contributes to the understanding of the complex network that controls root biology and strengthens the idea that ST proteins are involved in several processes such as primary and lateral root development, nodule organogenesis, and the plant-microbe interaction.
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Affiliation(s)
- Lucía Albornos
- Departamento de Botánica y Fisiología Vegetal, Universidad de Salamanca, C/ Licenciado Méndez Nieto s/n, Campus Miguel de Unamuno, 37007, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Campus de Villamayor, C/ Río Duero 12, Villamayor, 37185, Salamanca, Spain
| | - Virginia Casado-Del-Castillo
- Departamento de Microbiología y Genética, Universidad de Salamanca, Campus Miguel de Unamuno, Edificio departamental, 37007, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Campus de Villamayor, C/ Río Duero 12, Villamayor, 37185, Salamanca, Spain
| | - Ignacio Martín
- Departamento de Botánica y Fisiología Vegetal, Universidad de Salamanca, C/ Licenciado Méndez Nieto s/n, Campus Miguel de Unamuno, 37007, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Campus de Villamayor, C/ Río Duero 12, Villamayor, 37185, Salamanca, Spain
| | - José M Díaz-Mínguez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Campus Miguel de Unamuno, Edificio departamental, 37007, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Campus de Villamayor, C/ Río Duero 12, Villamayor, 37185, Salamanca, Spain
| | - Emilia Labrador
- Departamento de Botánica y Fisiología Vegetal, Universidad de Salamanca, C/ Licenciado Méndez Nieto s/n, Campus Miguel de Unamuno, 37007, Salamanca, Spain
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Campus de Villamayor, C/ Río Duero 12, Villamayor, 37185, Salamanca, Spain
| | - Berta Dopico
- Departamento de Botánica y Fisiología Vegetal, Universidad de Salamanca, C/ Licenciado Méndez Nieto s/n, Campus Miguel de Unamuno, 37007, Salamanca, Spain.
- Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Campus de Villamayor, C/ Río Duero 12, Villamayor, 37185, Salamanca, Spain.
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48
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Walker L, Lagunas B, Gifford ML. Determinants of Host Range Specificity in Legume-Rhizobia Symbiosis. Front Microbiol 2020; 11:585749. [PMID: 33329456 PMCID: PMC7728800 DOI: 10.3389/fmicb.2020.585749] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 11/06/2020] [Indexed: 01/24/2023] Open
Abstract
Leguminous plants possess the almost unique ability to enter symbiosis with soil-resident, nitrogen fixing bacteria called rhizobia. During this symbiosis, the bacteria physically colonize specialized organs on the roots of the host plant called nodules, where they reduce atmospheric nitrogen into forms that can be assimilated by the host plant and receive photosynthates in return. In order for nodule development to occur, there is extensive chemical cross-talk between both parties during the formative stages of the symbiosis. The vast majority of the legume family are capable of forming root nodules and typically rhizobia are only able to fix nitrogen within the context of this symbiotic association. However, many legume species only enter productive symbiosis with a few, or even single rhizobial species or strains, and vice-versa. Permitting symbiosis with only rhizobial strains that will be able to fix nitrogen with high efficiency is a crucial strategy for the host plant to prevent cheating by rhizobia. This selectivity is enforced at all stages of the symbiosis, with partner choice beginning during the initial communication between the plant and rhizobia. However, it can also be influenced even once nitrogen-fixing nodules have developed on the root. This review sets out current knowledge about the molecular mechanisms employed by both parties to influence host range during legume-rhizobia symbiosis.
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Affiliation(s)
- Liam Walker
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Beatriz Lagunas
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Miriam L Gifford
- School of Life Sciences, University of Warwick, Coventry, United Kingdom.,Warwick Integrative Synthetic Biology Centre, University of Warwick, Coventry, United Kingdom
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49
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Walton JH, Kontra‐Kováts G, Green RT, Domonkos Á, Horváth B, Brear EM, Franceschetti M, Kaló P, Balk J. The Medicago truncatula Vacuolar iron Transporter-Like proteins VTL4 and VTL8 deliver iron to symbiotic bacteria at different stages of the infection process. THE NEW PHYTOLOGIST 2020; 228:651-666. [PMID: 32521047 PMCID: PMC7540006 DOI: 10.1111/nph.16735] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/27/2020] [Indexed: 05/28/2023]
Abstract
The symbiotic relationship between legumes and rhizobium bacteria in root nodules has a high demand for iron, and questions remain regarding which transporters are involved. Here, we characterize two nodule-specific Vacuolar iron Transporter-Like (VTL) proteins in Medicago truncatula. Localization of fluorescent fusion proteins and mutant studies were carried out to correlate with existing RNA-seq data showing differential expression of VTL4 and VTL8 during early and late infection, respectively. The vtl4 insertion lines showed decreased nitrogen fixation capacity associated with more immature nodules and less elongated bacteroids. A mutant line lacking the tandemly-arranged VTL4-VTL8 genes, named 13U, was unable to develop functional nodules and failed to fix nitrogen, which was almost fully restored by expression of VTL8 alone. Using a newly developed lux reporter to monitor iron status of the bacteroids, a moderate decrease in luminescence signal was observed in vtl4 mutant nodules and a strong decrease in 13U nodules. Iron transport capability of VTL4 and VTL8 was shown by yeast complementation. These data indicate that VTL8, the closest homologue of SEN1 in Lotus japonicus, is the main route for delivering iron to symbiotic rhizobia. We propose that a failure in iron protein maturation leads to early senescence of the bacteroids.
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Affiliation(s)
- Jennifer H. Walton
- Department of Biological ChemistryJohn Innes CentreNorwichNR4 7UHUK
- School of Biological SciencesUniversity of East AngliaNorwichNR4 7TJUK
| | | | - Robert T. Green
- Department of Biological ChemistryJohn Innes CentreNorwichNR4 7UHUK
| | - Ágota Domonkos
- Agricultural Biotechnology InstituteNARICGödöllő2100Hungary
| | | | - Ella M. Brear
- School of Life and Environmental SciencesThe University of SydneySydneyNSW2006Australia
| | | | - Péter Kaló
- Agricultural Biotechnology InstituteNARICGödöllő2100Hungary
- Institute of Plant BiologyBiological Research CentreSzeged6726Hungary
| | - Janneke Balk
- Department of Biological ChemistryJohn Innes CentreNorwichNR4 7UHUK
- School of Biological SciencesUniversity of East AngliaNorwichNR4 7TJUK
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50
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Lindström K, Mousavi SA. Effectiveness of nitrogen fixation in rhizobia. Microb Biotechnol 2020; 13:1314-1335. [PMID: 31797528 PMCID: PMC7415380 DOI: 10.1111/1751-7915.13517] [Citation(s) in RCA: 124] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 11/13/2019] [Accepted: 11/13/2019] [Indexed: 12/01/2022] Open
Abstract
Biological nitrogen fixation in rhizobia occurs primarily in root or stem nodules and is induced by the bacteria present in legume plants. This symbiotic process has fascinated researchers for over a century, and the positive effects of legumes on soils and their food and feed value have been recognized for thousands of years. Symbiotic nitrogen fixation uses solar energy to reduce the inert N2 gas to ammonia at normal temperature and pressure, and is thus today, especially, important for sustainable food production. Increased productivity through improved effectiveness of the process is seen as a major research and development goal. The interaction between rhizobia and their legume hosts has thus been dissected at agronomic, plant physiological, microbiological and molecular levels to produce ample information about processes involved, but identification of major bottlenecks regarding efficiency of nitrogen fixation has proven to be complex. We review processes and results that contributed to the current understanding of this fascinating system, with focus on effectiveness of nitrogen fixation in rhizobia.
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Affiliation(s)
- Kristina Lindström
- Faculty of Biological and Environmental Sciences and Helsinki Institute of Sustainability Science (HELSUS)University of HelsinkiFI‐00014HelsinkiFinland
| | - Seyed Abdollah Mousavi
- Faculty of Biological and Environmental Sciences and Helsinki Institute of Sustainability Science (HELSUS)University of HelsinkiFI‐00014HelsinkiFinland
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