1
|
Deng JL, Zhao L, Wei H, Ye HX, Yang L, Sun L, Zhao Z, Murray JD, Liu CW. A deeply conserved amino acid required for VAPYRIN localization and function during legume-rhizobial symbiosis. THE NEW PHYTOLOGIST 2024; 243:14-22. [PMID: 38703001 DOI: 10.1111/nph.19779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/10/2024] [Indexed: 05/06/2024]
Affiliation(s)
- Jin-Li Deng
- MOE Key Laboratory for Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Li Zhao
- MOE Key Laboratory for Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Hong Wei
- The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Han-Xiao Ye
- MOE Key Laboratory for Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Li Yang
- MOE Key Laboratory for Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Linfeng Sun
- The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Zhong Zhao
- Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, MOE Key Laboratory for Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Jeremy D Murray
- National Key Laboratory of Plant Molecular Genetics, CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
- John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - Cheng-Wu Liu
- MOE Key Laboratory for Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| |
Collapse
|
2
|
Gao JP, Liang W, Liu CW, Xie F, Murray JD. Unraveling the rhizobial infection thread. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2235-2245. [PMID: 38262702 DOI: 10.1093/jxb/erae017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 01/23/2024] [Indexed: 01/25/2024]
Abstract
Most legumes can form an endosymbiotic association with soil bacteria called rhizobia, which colonize specialized root structures called nodules where they fix nitrogen. To colonize nodule cells, rhizobia must first traverse the epidermis and outer cortical cell layers of the root. In most legumes, this involves formation of the infection thread, an intracellular structure that becomes colonized by rhizobia, guiding their passage through the outer cell layers of the root and into the newly formed nodule cells. In this brief review, we recount the early research milestones relating to the rhizobial infection thread and highlight two relatively recent advances in the symbiotic infection mechanism, the eukaryotically conserved 'MYB-AUR1-MAP' mitotic module, which links cytokinesis mechanisms to intracellular infection, and the discovery of the 'infectosome' complex, which guides infection thread growth. We also discuss the potential intertwining of the two modules and the hypothesis that cytokinesis served as a foundation for intracellular infection of symbiotic microbes.
Collapse
Affiliation(s)
- Jin-Peng Gao
- National Key Laboratory of Plant Molecular Genetics, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Wenjie Liang
- National Key Laboratory of Plant Molecular Genetics, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Cheng-Wu Liu
- School of Life Sciences, Division of Life Sciences and Medicine, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, University of Science and Technology of China, Hefei 230026, China
| | - Fang Xie
- National Key Laboratory of Plant Molecular Genetics, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jeremy D Murray
- National Key Laboratory of Plant Molecular Genetics, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 200032, China
- John Innes Centre, CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Norwich Research Park, Norwich NR4 7UH, UK
| |
Collapse
|
3
|
Abstract
Plants associate with nitrogen-fixing bacteria to secure nitrogen, which is generally the most limiting nutrient for plant growth. Endosymbiotic nitrogen-fixing associations are widespread among diverse plant lineages, ranging from microalgae to angiosperms, and are primarily one of three types: cyanobacterial, actinorhizal or rhizobial. The large overlap in the signaling pathways and infection components of arbuscular mycorrhizal, actinorhizal and rhizobial symbioses reflects their evolutionary relatedness. These beneficial associations are influenced by environmental factors and other microorganisms in the rhizosphere. In this review, we summarize the diversity of nitrogen-fixing symbioses, key signal transduction pathways and colonization mechanisms relevant to such interactions, and compare and contrast these interactions with arbuscular mycorrhizal associations from an evolutionary standpoint. Additionally, we highlight recent studies on environmental factors regulating nitrogen-fixing symbioses to provide insights into the adaptation of symbiotic plants to complex environments.
Collapse
Affiliation(s)
- Peng Xu
- 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
- 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; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; New Cornerstone Science Laboratory, Shenzhen 518054, China.
| |
Collapse
|
4
|
Jhu MY, Oldroyd GED. Dancing to a different tune, can we switch from chemical to biological nitrogen fixation for sustainable food security? PLoS Biol 2023; 21:e3001982. [PMID: 36917569 PMCID: PMC10013914 DOI: 10.1371/journal.pbio.3001982] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Our current food production systems are unsustainable, driven in part through the application of chemically fixed nitrogen. We need alternatives to empower farmers to maximise their productivity sustainably. Therefore, we explore the potential for transferring the root nodule symbiosis from legumes to other crops. Studies over the last decades have shown that preexisting developmental and signal transduction processes were recruited during the evolution of legume nodulation. This allows us to utilise these preexisting processes to engineer nitrogen fixation in target crops. Here, we highlight our understanding of legume nodulation and future research directions that might help to overcome the barrier of achieving self-fertilising crops.
Collapse
Affiliation(s)
- Min-Yao Jhu
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Giles E. D. Oldroyd
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
5
|
Lace B, Su C, Invernot Perez D, Rodriguez-Franco M, Vernié T, Batzenschlager M, Egli S, Liu CW, Ott T. RPG acts as a central determinant for infectosome formation and cellular polarization during intracellular rhizobial infections. eLife 2023; 12:80741. [PMID: 36856086 PMCID: PMC9991063 DOI: 10.7554/elife.80741] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 02/21/2023] [Indexed: 03/02/2023] Open
Abstract
Host-controlled intracellular accommodation of nitrogen-fixing bacteria is essential for the establishment of a functional Root Nodule Symbiosis (RNS). In many host plants, this occurs via transcellular tubular structures (infection threads - ITs) that extend across cell layers via polar tip-growth. Comparative phylogenomic studies have identified RPG (RHIZOBIUM-DIRECTED POLAR GROWTH) among the critical genetic determinants for bacterial infection. In Medicago truncatula, RPG is required for effective IT progression within root hairs but the cellular and molecular function of the encoded protein remains elusive. Here, we show that RPG resides in the protein complex formed by the core endosymbiotic components VAPYRIN (VPY) and LUMPY INFECTION (LIN) required for IT polar growth, co-localizes with both VPY and LIN in IT tip- and perinuclear-associated puncta of M. truncatula root hairs undergoing infection and is necessary for VPY recruitment into these structures. Fluorescence Lifetime Imaging Microscopy (FLIM) of phosphoinositide species during bacterial infection revealed that functional RPG is required to sustain strong membrane polarization at the advancing tip of the IT. In addition, loss of RPG functionality alters the cytoskeleton-mediated connectivity between the IT tip and the nucleus and affects the polar secretion of the cell wall modifying enzyme NODULE PECTATE LYASE (NPL). Our results integrate RPG into a core host machinery required to support symbiont accommodation, suggesting that its occurrence in plant host genomes is essential to co-opt a multimeric protein module committed to endosymbiosis to sustain IT-mediated bacterial infection.
Collapse
Affiliation(s)
- Beatrice Lace
- University of Freiburg, Faculty of BiologyFreiburgGermany
| | - Chao Su
- University of Freiburg, Faculty of BiologyFreiburgGermany
| | | | | | - Tatiana Vernié
- LRSV, Université de Toulouse, CNRS, UPS, INP ToulouseCastanet-TolosanFrance
| | | | - Sabrina Egli
- University of Freiburg, Faculty of BiologyFreiburgGermany
| | - Cheng-Wu Liu
- School of Life Sciences, Division of Life Sciences and Medicine, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, University of Science and Technology of ChinaHefeiChina
| | - Thomas Ott
- University of Freiburg, Faculty of BiologyFreiburgGermany
- CIBSS – Centre of Integrative Biological Signalling Studies, University of FreiburgFreiburgGermany
| |
Collapse
|
6
|
Li X, Liu M, Cai M, Chiasson D, Groth M, Heckmann AB, Wang TL, Parniske M, Downie JA, Xie F. RPG interacts with E3-ligase CERBERUS to mediate rhizobial infection in Lotus japonicus. PLoS Genet 2023; 19:e1010621. [PMID: 36735729 PMCID: PMC9931111 DOI: 10.1371/journal.pgen.1010621] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 02/15/2023] [Accepted: 01/17/2023] [Indexed: 02/04/2023] Open
Abstract
Symbiotic interactions between rhizobia and legumes result in the formation of root nodules, which fix nitrogen that can be used for plant growth. Rhizobia usually invade legume roots through a plant-made tunnel-like structure called an infection thread (IT). RPG (Rhizobium-directed polar growth) encodes a coiled-coil protein that has been identified in Medicago truncatula as required for root nodule infection, but the function of RPG remains poorly understood. In this study, we identified and characterized RPG in Lotus japonicus and determined that it is required for IT formation. RPG was induced by Mesorhizobium loti or purified Nodulation factor and displayed an infection-specific expression pattern. Nodule inception (NIN) bound to the RPG promoter and induced its expression. We showed that RPG displayed punctate subcellular localization in L. japonicus root protoplasts and in root hairs infected by M. loti. The N-terminal predicted C2 lipid-binding domain of RPG was not required for this subcellular localization or for function. CERBERUS, a U-box E3 ligase which is also required for rhizobial infection, was found to be localized similarly in puncta. RPG co-localized and directly interacted with CERBERUS in the early endosome (TGN/EE) compartment and near the nuclei in root hairs after rhizobial inoculation. Our study sheds light on an RPG-CERBERUS protein complex that is involved in an exocytotic pathway mediating IT elongation.
Collapse
Affiliation(s)
- Xiaolin Li
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Miaoxia Liu
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Min Cai
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - David Chiasson
- Faculty of Biology, University of Munich, Großhaderner Straße 2–4, Planegg-Martinsried, Germany
| | - Martin Groth
- Faculty of Biology, University of Munich, Großhaderner Straße 2–4, Planegg-Martinsried, Germany
| | - Anne B. Heckmann
- John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Trevor L. Wang
- John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Martin Parniske
- Faculty of Biology, University of Munich, Großhaderner Straße 2–4, Planegg-Martinsried, Germany
| | - J. Allan Downie
- John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Fang Xie
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- * E-mail:
| |
Collapse
|
7
|
Wang N, Yin Z, Zhao Y, Wang J, Pei Y, Ji P, Daly P, Li Z, Dou D, Wei L. An F-box protein attenuates fungal xylanase-triggered immunity by destabilizing LRR-RLP NbEIX2 in a SOBIR1-dependent manner. THE NEW PHYTOLOGIST 2022; 236:2202-2215. [PMID: 36151918 DOI: 10.1111/nph.18509] [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: 04/01/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
Receptor-like proteins (RLPs) lacking the cytoplasmic kinase domain play crucial roles in plant growth, development and immunity. However, what remains largely elusive is whether RLP protein levels are fine-tuned by E3 ubiquitin ligases, which are employed by receptor-like kinases for signaling attenuation. Nicotiana benthamiana NbEIX2 is a leucine-rich repeat RLP (LRR-RLP) that mediates fungal xylanase-triggered immunity. Here we show that NbEIX2 associates with an F-box protein NbPFB1, which promotes NbEIX2 degradation likely by forming an SCF E3 ubiquitin ligase complex, and negatively regulates NbEIX2-mediated immune responses. NbEIX2 undergoes ubiquitination and proteasomal degradation in planta. Interestingly, NbEIX2 without its cytoplasmic tail is still associated with and destabilized by NbPFB1. In addition, NbPFB1 also associates with and destabilizes NbSOBIR1, a co-receptor of LRR-RLPs, and fails to promote NbEIX2 degradation in the sobir1 mutant. Our findings reveal a distinct model of NbEIX2 degradation, in which an F-box protein destabilizes NbEIX2 indirectly in a SOBIR1-dependent manner.
Collapse
Affiliation(s)
- Nan Wang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, 210014, Nanjing, China
| | - Zhiyuan Yin
- College of Plant Protection, Nanjing Agricultural University, 210095, Nanjing, China
| | - Yaning Zhao
- College of Plant Protection, Nanjing Agricultural University, 210095, Nanjing, China
| | - Jinghao Wang
- College of Plant Protection, China Agricultural University, 100193, Beijing, China
| | - Yong Pei
- College of Plant Protection, Nanjing Agricultural University, 210095, Nanjing, China
| | - Peiyun Ji
- College of Plant Protection, Nanjing Agricultural University, 210095, Nanjing, China
| | - Paul Daly
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, 210014, Nanjing, China
| | - Zhengpeng Li
- Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake, School of Life Sciences, Huaiyin Normal University, 223300, Huaian, China
| | - Daolong Dou
- College of Plant Protection, Nanjing Agricultural University, 210095, Nanjing, China
| | - Lihui Wei
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, 210014, Nanjing, China
| |
Collapse
|
8
|
Kohli PS, Pazhamala LT, Mani B, Thakur JK, Giri J. Root hair-specific transcriptome reveals response to low phosphorus in Cicer arietinum. FRONTIERS IN PLANT SCIENCE 2022; 13:983969. [PMID: 36267945 PMCID: PMC9577374 DOI: 10.3389/fpls.2022.983969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/16/2022] [Indexed: 06/16/2023]
Abstract
Root hairs (RH) are a single-cell extension of root epidermal cells. In low phosphorus (LP) availability, RH length and density increase thus expanding the total root surface area for phosphate (Pi) acquisition. However, details on genes involved in RH development and response to LP are missing in an agronomically important leguminous crop, chickpea. To elucidate this response in chickpea, we performed tissue-specific RNA-sequencing and analyzed the transcriptome modulation for RH and root without RH (Root-RH) under LP. Root hair initiation and cellular differentiation genes like RSL TFs and ROPGEFs are upregulated in Root-RH, explaining denser, and ectopic RH in LP. In RH, genes involved in tip growth processes and phytohormonal biosynthesis like cell wall synthesis and loosening (cellulose synthase A catalytic subunit, CaEXPA2, CaGRP2, and CaXTH2), cytoskeleton/vesicle transport, and ethylene biosynthesis are upregulated. Besides RH development, genes involved in LP responses like lipid and/or pectin P remobilization and acid phosphatases are induced in these tissues summarizing a complete molecular response to LP. Further, RH displayed preferential enrichment of processes involved in symbiotic interactions, which provide an additional benefit during LP. In conclusion, RH shows a multi-faceted response that starts with molecular changes for epidermal cell differentiation and RH initiation in Root-RH and later induction of tip growth and various LP responses in elongated RH.
Collapse
Affiliation(s)
| | | | - Balaji Mani
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
| | - Jitendra Kumar Thakur
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
- International Center of Genetic Engineering and Biotechnology, New Delhi, India
| | - Jitender Giri
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
| |
Collapse
|
9
|
Lindsay PL, Ivanov S, Pumplin N, Zhang X, Harrison MJ. Distinct ankyrin repeat subdomains control VAPYRIN locations and intracellular accommodation functions during arbuscular mycorrhizal symbiosis. Nat Commun 2022; 13:5228. [PMID: 36064777 PMCID: PMC9445082 DOI: 10.1038/s41467-022-32124-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 07/18/2022] [Indexed: 11/25/2022] Open
Abstract
Over 70% of vascular flowering plants engage in endosymbiotic associations with arbuscular mycorrhizal (AM) fungi. VAPYRIN (VPY) is a plant protein that is required for intracellular accommodation of AM fungi but how it functions is still unclear. VPY has a large ankyrin repeat domain with potential for interactions with multiple proteins. Here we show that overexpression of the ankyrin repeat domain results in a vpy-like phenotype, consistent with the sequestration of interacting proteins. We identify distinct ankyrin repeats that are essential for intracellular accommodation of arbuscules and reveal that VPY functions in both the cytoplasm and nucleus. VPY interacts with two kinases, including DOES NOT MAKE INFECTIONS3 (DMI3), a nuclear-localized symbiosis signaling kinase. Overexpression of VPY in a symbiosis-attenuated genetic background results in a dmi3 -like phenotype suggesting that VPY negatively influences DMI3 function. Overall, the data indicate a requirement for VPY in the nucleus and cytoplasm where it may coordinate signaling and cellular accommodation processes. VAPYRIN is a plant protein required for symbiosis with arbuscular mycorrhizal fungi. Here the authors identify VAPYRIN domains that control subcellular targeting and protein-protein interactions and propose that VAPYRIN acts in the nucleus and cytoplasm to coordinate signaling and intracellular arbuscule accommodation.
Collapse
Affiliation(s)
- Penelope L Lindsay
- Boyce Thompson Institute, 533 Tower Rd., Ithaca, NY, 14853, USA.,School of Integrative Plant Science, Plant Biology Section, Cornell University, Ithaca, NY, USA.,PLL: Cold Spring Harbor Laboratory, 1 Bungtown Rd, Cold Spring Harbor, NY, 11724, USA
| | - Sergey Ivanov
- Boyce Thompson Institute, 533 Tower Rd., Ithaca, NY, 14853, USA
| | - Nathan Pumplin
- Boyce Thompson Institute, 533 Tower Rd., Ithaca, NY, 14853, USA.,School of Integrative Plant Science, Plant Biology Section, Cornell University, Ithaca, NY, USA
| | - Xinchun Zhang
- Boyce Thompson Institute, 533 Tower Rd., Ithaca, NY, 14853, USA
| | - Maria J Harrison
- Boyce Thompson Institute, 533 Tower Rd., Ithaca, NY, 14853, USA.
| |
Collapse
|
10
|
Constitutive activation of a nuclear-localized calcium channel complex in Medicago truncatula. Proc Natl Acad Sci U S A 2022; 119:e2205920119. [PMID: 35972963 PMCID: PMC9407390 DOI: 10.1073/pnas.2205920119] [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] [Indexed: 11/18/2022] Open
Abstract
Nuclear Ca2+ oscillations allow symbiosis signaling, facilitating plant recognition of beneficial microsymbionts, nitrogen-fixing rhizobia, and nutrient-capturing arbuscular mycorrhizal fungi. Two classes of channels, DMI1 and CNGC15, in a complex on the nuclear membrane, coordinate symbiotic Ca2+ oscillations. However, the mechanism of Ca2+ signature generation is unknown. Here, we demonstrate spontaneous activation of this channel complex, through gain-of-function mutations in DMI1, leading to spontaneous nuclear Ca2+ oscillations and spontaneous nodulation, in a CNGC15-dependent manner. The mutations destabilize a hydrogen-bond or salt-bridge network between two RCK domains, with the resultant structural changes, alongside DMI1 cation permeability, activating the channel complex. This channel complex was reconstituted in human HEK293T cell lines, with the resultant calcium influx enhanced by autoactivated DMI1 and CNGC15s. Our results demonstrate the mode of activation of this nuclear channel complex, show that DMI1 and CNGC15 are sufficient to create oscillatory Ca2+ signals, and provide insights into its native mode of induction.
Collapse
|
11
|
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.
Collapse
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.)
| |
Collapse
|
12
|
Structure and Development of the Legume-Rhizobial Symbiotic Interface in Infection Threads. Cells 2021; 10:cells10051050. [PMID: 33946779 PMCID: PMC8146911 DOI: 10.3390/cells10051050] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/25/2021] [Accepted: 04/27/2021] [Indexed: 02/06/2023] Open
Abstract
The intracellular infection thread initiated in a root hair cell is a unique structure associated with Rhizobium-legume symbiosis. It is characterized by inverted tip growth of the plant cell wall, resulting in a tunnel that allows invasion of host cells by bacteria during the formation of the nitrogen-fixing root nodule. Regulation of the plant-microbial interface is essential for infection thread growth. This involves targeted deposition of the cell wall and extracellular matrix and tight control of cell wall remodeling. This review describes the potential role of different actors such as transcription factors, receptors, and enzymes in the rearrangement of the plant-microbial interface and control of polar infection thread growth. It also focuses on the composition of the main polymers of the infection thread wall and matrix and the participation of reactive oxygen species (ROS) in the development of the infection thread. Mutant analysis has helped to gain insight into the development of host defense reactions. The available data raise many new questions about the structure, function, and development of infection threads.
Collapse
|