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Schuster CD, Salvatore F, Moens L, Martí MA. Globin phylogeny, evolution and function, the newest update. Proteins 2024; 92:720-734. [PMID: 38192262 DOI: 10.1002/prot.26659] [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: 09/06/2023] [Revised: 11/22/2023] [Accepted: 12/15/2023] [Indexed: 01/10/2024]
Abstract
Our globin census update allows us to refine our vision of globin origin, evolution, and structure to function relationship in the context of the currently accepted tree of life. The modern globin domain originates as a single domain, three-over-three α-helical folded structure before the diversification of the kingdoms of life (Bacteria, Archaea, Eukarya). Together with the diversification of prokaryotes, three monophyletic globin families (M, S, and T) emerged, most likely in Proteobacteria and Actinobacteria, displaying specific sequence and structural features, and spread by vertical and horizontal gene transfer, most probably already present in the last universal common ancestor (LUCA). Non-globin domains were added, and eventually lost again, creating multi-domain structures in key branches of M- (FHb and Adgb) and the vast majority of S globins, which with their coevolved multi-domain architectures, have predominantly "sensor" functions. Single domain T-family globins diverged into four major groups and most likely display functions related to reactive nitrogen and oxygen species (RNOS) chemistry, as well as oxygen storage/transport which drives the evolution of its major branches with their characteristic key distal residues (B10, E11, E7, and G8). M-family evolution also lead to distinctive major types (FHb and Fgb, Ngb, Adgb, GbX vertebrate Gbs), and shows the shift from high oxygen affinity controlled by TyrB10-Gln/AsnE11 likely related to RNOS chemistry in microorganisms, to a moderate oxygen affinity storage/transport function controlled by hydrophobic B10/E11-HisE7 in multicellular animals.
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Affiliation(s)
- Claudio David Schuster
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), Ciudad Autónoma de Buenos Aires, Argentina
- Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Franco Salvatore
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), Ciudad Autónoma de Buenos Aires, Argentina
- Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Luc Moens
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Marcelo Adrián Martí
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), Ciudad Autónoma de Buenos Aires, Argentina
- Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), CONICET, Ciudad Autónoma de Buenos Aires, Argentina
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Wang M, Shi Z, Gao N, Zhou Y, Ni X, Chen J, Liu J, Zhou W, Guo X, Xin B, Shen Y, Wang Y, Zheng P, Sun J. Sustainable and high-level microbial production of plant hemoglobin in Corynebacterium glutamicum. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:80. [PMID: 37170167 PMCID: PMC10176901 DOI: 10.1186/s13068-023-02337-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 05/03/2023] [Indexed: 05/13/2023]
Abstract
BACKGROUND Plant hemoglobin shows great potential as a food additive to circumvent the controversy of using animal materials. Microbial fermentation with engineered microorganisms is considered as a promising strategy for sustainable production of hemoglobin. As an endotoxin-free and GRAS (generally regarded as safe) bacterium, Corynebacterium glutamicum is an attractive host for hemoglobin biosynthesis. RESULTS Herein, C. glutamicum was engineered to efficiently produce plant hemoglobin. Hemoglobin genes from different sources including soybean and maize were selected and subjected to codon optimization. Interestingly, some candidates optimized for the codon usage bias of Escherichia coli outperformed those for C. glutamicum regarding the heterologous expression in C. glutamicum. Then, saturated synonymous mutation of the N-terminal coding sequences of hemoglobin genes and fluorescence-based high-throughput screening produced variants with 1.66- to 3.45-fold increase in hemoglobin expression level. To avoid the use of toxic inducers, such as isopropyl-β-D-thiogalactopyranoside, two native inducible expression systems based on food additives propionate and gluconate were developed. Promoter engineering improved the hemoglobin expression level by 2.2- to 12.2-fold. Combination of these strategies and plasmid copy number modification allowed intracellular production of hemoglobin up to approximately 20% of total protein. Transcriptome and proteome analyses of the hemoglobin-producing strain revealed the cellular response to excess hemoglobin accumulation. Several genes were identified as potential targets for further enhancing hemoglobin production. CONCLUSIONS In this study, production of plant hemoglobin in C. glutamicum was systematically engineered by combining codon optimization, promoter engineering, plasmid copy number modification, and multi-omics-guided novel target discovery. This study offers useful design principles to genetically engineer C. glutamicum for the production of hemoglobin and other recombinant proteins.
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Affiliation(s)
- Mengmeng Wang
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300222, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Zhong Shi
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China
| | - Ning Gao
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yingyu Zhou
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300222, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Xiaomeng Ni
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Jiuzhou Chen
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Jiao Liu
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Wenjuan Zhou
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Xuan Guo
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Bo Xin
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300222, China
| | - Yanbing Shen
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300222, China
| | - Yu Wang
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ping Zheng
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Jibin Sun
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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Oxidative Implications of Substituting a Conserved Cysteine Residue in Sugar Beet Phytoglobin BvPgb 1.2. Antioxidants (Basel) 2022; 11:antiox11081615. [PMID: 36009334 PMCID: PMC9404779 DOI: 10.3390/antiox11081615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/09/2022] [Accepted: 08/17/2022] [Indexed: 11/17/2022] Open
Abstract
Phytoglobins (Pgbs) are plant-originating heme proteins of the globin superfamily with varying degrees of hexacoordination. Pgbs have a conserved cysteine residue, the role of which is poorly understood. In this paper, we investigated the functional and structural role of cysteine in BvPgb1.2, a Class 1 Pgb from sugar beet (Beta vulgaris), by constructing an alanine-substituted mutant (Cys86Ala). The substitution had little impact on structure, dimerization, and heme loss as determined by X-ray crystallography, size-exclusion chromatography, and an apomyoglobin-based heme-loss assay, respectively. The substitution significantly affected other important biochemical properties. The autoxidation rate increased 16.7- and 14.4-fold for the mutant versus the native protein at 25 °C and 37 °C, respectively. Thermal stability similarly increased for the mutant by ~2.5 °C as measured by nano-differential scanning fluorimetry. Monitoring peroxidase activity over 7 days showed a 60% activity decrease in the native protein, from 33.7 to 20.2 U/mg protein. When comparing the two proteins, the mutant displayed a remarkable enzymatic stability as activity remained relatively constant throughout, albeit at a lower level, ~12 U/mg protein. This suggests that cysteine plays an important role in BvPgb1.2 function and stability, despite having seemingly little effect on its tertiary and quaternary structure.
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Chatelain P, Astier J, Wendehenne D, Rosnoblet C, Jeandroz S. Identification of Partner Proteins of the Algae Klebsormidium nitens NO Synthases: Toward a Better Understanding of NO Signaling in Eukaryotic Photosynthetic Organisms. FRONTIERS IN PLANT SCIENCE 2021; 12:797451. [PMID: 35003186 PMCID: PMC8728061 DOI: 10.3389/fpls.2021.797451] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
Abstract
In animals, NO is synthesized from L-arginine by three isoforms of nitric oxide synthase (NOS) enzyme. NO production and effects have also been reported in plants but the identification of its sources, especially the enzymatic ones, remains one of the critical issues in the field. NOS-like activities have been reported, although there are no homologs of mammalian NOS in the land plant genomes sequenced so far. However, several NOS homologs have been found in algal genomes and transcriptomes. A first study has characterized a functional NOS in the chlorophyte Ostreococcus tauri and the presence of NOS homologs was later confirmed in a dozen algae. These results raise the questions of the significance of the presence of NOS and their molecular diversity in algae. We hypothesize that comparisons among protein structures of the two KnNOS, together with the identification of their interacting partner proteins, might allow a better understanding of the molecular diversification and functioning of NOS in different physiological contexts and, more generally, new insights into NO signaling in photosynthetic organisms. We recently identified two NOS homologs sequences in the genome of the streptophyte Klebsormidium nitens, a model alga in the study of plant adaptation to terrestrial life. The first sequence, named KnNOS1, contains canonical NOS signatures while the second, named KnNOS2, presents a large C-ter extension including a globin domain. In order to identify putative candidates for KnNOSs partner proteins, we draw the protein-protein interaction networks of the three human NOS using the BioGRID database and hypothesized on the biological role of K. nitens orthologs. Some of these conserved partners are known to be involved in mammalian NOSs regulation and functioning. In parallel, our methodological strategy for the identification of partner proteins of KnNOS1 and KnNOS2 by in vitro pull-down assay is presented.
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Jiang S, Jardinaud MF, Gao J, Pecrix Y, Wen J, Mysore K, Xu P, Sanchez-Canizares C, Ruan Y, Li Q, Zhu M, Li F, Wang E, Poole PS, Gamas P, Murray JD. NIN-like protein transcription factors regulate leghemoglobin genes in legume nodules. Science 2021; 374:625-628. [PMID: 34709882 DOI: 10.1126/science.abg5945] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Suyu Jiang
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China
| | | | - Jinpeng Gao
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China
| | - Yann Pecrix
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France.,CIRAD, UMR PVBMT, Pôle de Protection des Plantes, Saint-Pierre 97410, France
| | - Jiangqi Wen
- Noble Research Institute, Ardmore, OK 73401, USA
| | | | - Ping Xu
- Shanghai Engineering Research Center of Plant Germplasm Resource, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | | | - Yiting Ruan
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China
| | - Qiujiu Li
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China
| | - Meijun Zhu
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China
| | - Fuyu Li
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China
| | - Ertao Wang
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China
| | - Phillip S Poole
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
| | - Pascal Gamas
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - Jeremy D Murray
- CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Centre for Excellence in Molecular Plant Sciences (CEMPS), Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, China.,John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
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Belato FA, Coates CJ, Halanych KM, Weber RE, Costa-Paiva EM. Evolutionary History of the Globin Gene Family in Annelids. Genome Biol Evol 2020; 12:1719-1733. [PMID: 32597988 PMCID: PMC7549130 DOI: 10.1093/gbe/evaa134] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2020] [Indexed: 12/20/2022] Open
Abstract
Animals depend on the sequential oxidation of organic molecules to survive; thus, oxygen-carrying/transporting proteins play a fundamental role in aerobic metabolism. Globins are the most common and widespread group of respiratory proteins. They can be divided into three types: circulating intracellular, noncirculating intracellular, and extracellular, all of which have been reported in annelids. The diversity of oxygen transport proteins has been underestimated across metazoans. We probed 250 annelid transcriptomes in search of globin diversity in order to elucidate the evolutionary history of this gene family within this phylum. We report two new globin types in annelids, namely androglobins and cytoglobins. Although cytoglobins and myoglobins from vertebrates and from invertebrates are referred to by the same name, our data show they are not genuine orthologs. Our phylogenetic analyses show that extracellular globins from annelids are more closely related to extracellular globins from other metazoans than to the intracellular globins of annelids. Broadly, our findings indicate that multiple gene duplication and neo-functionalization events shaped the evolutionary history of the globin family.
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Affiliation(s)
- Flávia A Belato
- Department of Zoology, Institute of Biosciences, University of Sao Paulo, Brazil
| | - Christopher J Coates
- Department of Biosciences, College of Science, Swansea University, United Kingdom
| | - Kenneth M Halanych
- Department of Biological Sciences, Molette Biology Laboratory for Environmental and Climate Change Studies, Auburn University
| | - Roy E Weber
- Zoophysiology, Department of Biology, Aarhus University, Denmark
| | - Elisa M Costa-Paiva
- Department of Zoology, Institute of Biosciences, University of Sao Paulo, Brazil
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Larrainzar E, Villar I, Rubio MC, Pérez-Rontomé C, Huertas R, Sato S, Mun JH, Becana M. Hemoglobins in the legume-Rhizobium symbiosis. THE NEW PHYTOLOGIST 2020; 228:472-484. [PMID: 32442331 DOI: 10.1111/nph.16673] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/13/2020] [Indexed: 05/23/2023]
Abstract
Legume nodules have two types of hemoglobins: symbiotic or leghemoglobins (Lbs) and nonsymbiotic or phytoglobins (Glbs). The latter are categorized into three phylogenetic classes differing in heme coordination and O2 affinity. This review is focused on the roles of Lbs and Glbs in the symbiosis of rhizobia with crop legumes and the model legumes for indeterminate (Medicago truncatula) and determinate (Lotus japonicus) nodulation. Only two hemoglobin functions are well established in nodules: Lbs deliver O2 to the bacteroids and act as O2 buffers, preventing nitrogenase inactivation; and Glb1-1 modulates nitric oxide concentration during symbiosis, from the early stage, avoiding the plant's defense response, to nodule senescence. Here, we critically examine early and recent results, update and correct the information on Lbs and Glbs with the latest genome versions, provide novel expression data and identify targets for future research. Crucial unresolved questions include the expression of multiple Lbs in nodules, their presence in the nuclei and in uninfected nodule cells, and, intriguingly, their expression in nonsymbiotic tissues. RNA-sequencing data analysis shows that Lbs are expressed as early as a few hours after inoculation and that their mRNAs are also detectable in roots and pods, which clearly suggests that these heme proteins play additional roles unrelated to nitrogen fixation. Likewise, issues awaiting investigation are the functions of other Glbs in nodules, the spatiotemporal expression profiles of Lbs and Glbs at the mRNA and protein levels, and the molecular mechanisms underlying their regulation during nodule development and in response to stress and hormones.
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Affiliation(s)
- Estíbaliz Larrainzar
- Institute for Multidisciplinary Research in Applied Biology (IMAB), Universidad Pública de Navarra, Campus de Arrosadía, 31006, Pamplona, Spain
| | - Irene Villar
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080, Zaragoza, Spain
| | - Maria Carmen Rubio
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080, Zaragoza, Spain
| | - Carmen Pérez-Rontomé
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080, Zaragoza, Spain
| | - Raul Huertas
- Noble Research Institute LLC, 2510 Sam Noble Pkwy, Ardmore, OK, 73401, USA
| | - Shusei Sato
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan
| | - Jeong-Hwan Mun
- Department of Bioscience and Bioinformatics, Myongji University, Yongin, 17058, Korea
| | - Manuel Becana
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080, Zaragoza, Spain
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Liu A, Ku YS, Contador CA, Lam HM. The Impacts of Domestication and Agricultural Practices on Legume Nutrient Acquisition Through Symbiosis With Rhizobia and Arbuscular Mycorrhizal Fungi. Front Genet 2020; 11:583954. [PMID: 33193716 PMCID: PMC7554533 DOI: 10.3389/fgene.2020.583954] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 09/08/2020] [Indexed: 12/03/2022] Open
Abstract
Legumes are unique among plants as they can obtain nitrogen through symbiosis with nitrogen-fixing rhizobia that form root nodules in the host plants. Therefore they are valuable crops for sustainable agriculture. Increasing nitrogen fixation efficiency is not only important for achieving better plant growth and yield, but it is also crucial for reducing the use of nitrogen fertilizer. Arbuscular mycorrhizal fungi (AMF) are another group of important beneficial microorganisms that form symbiotic relationships with legumes. AMF can promote host plant growth by providing mineral nutrients and improving the soil ecosystem. The trilateral legume-rhizobia-AMF symbiotic relationships also enhance plant development and tolerance against biotic and abiotic stresses. It is known that domestication and agricultural activities have led to the reduced genetic diversity of cultivated germplasms and higher sensitivity to nutrient deficiencies in crop plants, but how domestication has impacted the capability of legumes to establish beneficial associations with rhizospheric microbes (including rhizobia and fungi) is not well-studied. In this review, we will discuss the impacts of domestication and agricultural practices on the interactions between legumes and soil microbes, focusing on the effects on AMF and rhizobial symbioses and hence nutrient acquisition by host legumes. In addition, we will summarize the genes involved in legume-microbe interactions and studies that have contributed to a better understanding of legume symbiotic associations using metabolic modeling.
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Affiliation(s)
| | | | | | - Hon-Ming Lam
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
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Becana M, Yruela I, Sarath G, Catalán P, Hargrove MS. Plant hemoglobins: a journey from unicellular green algae to vascular plants. THE NEW PHYTOLOGIST 2020; 227:1618-1635. [PMID: 31960995 DOI: 10.1111/nph.16444] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 12/24/2019] [Indexed: 05/17/2023]
Abstract
Globins (Glbs) are widely distributed in archaea, bacteria and eukaryotes. They can be classified into proteins with 2/2 or 3/3 α-helical folding around the heme cavity. Both types of Glbs occur in green algae, bryophytes and vascular plants. The Glbs of angiosperms have been more intensively studied, and several protein structures have been solved. They can be hexacoordinate or pentacoordinate, depending on whether a histidine is coordinating or not at the sixth position of the iron atom. The 3/3 Glbs of class 1 and the 2/2 Glbs (also called class 3 in plants) are present in all angiosperms, whereas the 3/3 Glbs of class 2 have been only found in early angiosperms and eudicots. The three Glb classes are expected to play different roles. Class 1 Glbs are involved in hypoxia responses and modulate NO concentration, which may explain their roles in plant morphogenesis, hormone signaling, cell fate determination, nutrient deficiency, nitrogen metabolism and plant-microorganism symbioses. Symbiotic Glbs derive from class 1 or class 2 Glbs and transport O2 in nodules. The physiological roles of class 2 and class 3 Glbs are poorly defined but could involve O2 and NO transport and/or metabolism, respectively. More research is warranted on these intriguing proteins to determine their non-redundant functions.
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Affiliation(s)
- Manuel Becana
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Apartado 13034, 50080, Zaragoza, Spain
| | - Inmaculada Yruela
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Apartado 13034, 50080, Zaragoza, Spain
- Group of Biochemistry, Biophysics and Computational Biology (BIFI-Unizar) Joint Unit to CSIC, Edificio I+D Campus Río Ebro, 50018, Zaragoza, Spain
| | - Gautam Sarath
- Wheat, Sorghum, and Forage Research Unit, USDA-ARS, East Campus, University of Nebraska-Lincoln, Lincoln, NE, 86583, USA
| | - Pilar Catalán
- Group of Biochemistry, Biophysics and Computational Biology (BIFI-Unizar) Joint Unit to CSIC, Edificio I+D Campus Río Ebro, 50018, Zaragoza, Spain
- Escuela Politécnica Superior de Huesca, Universidad de Zaragoza, 22071, Huesca, Spain
| | - Mark S Hargrove
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
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Lessons from the post-genomic era: Globin diversity beyond oxygen binding and transport. Redox Biol 2020; 37:101687. [PMID: 32863222 PMCID: PMC7475203 DOI: 10.1016/j.redox.2020.101687] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/11/2020] [Accepted: 08/11/2020] [Indexed: 12/16/2022] Open
Abstract
Vertebrate hemoglobin (Hb) and myoglobin (Mb) were among the first proteins whose structures and sequences were determined over 50 years ago. In the subsequent pregenomic period, numerous related proteins came to light in plants, invertebrates and bacteria, that shared the myoglobin fold, a signature sequence motif characteristic of a 3-on-3 α-helical sandwich. Concomitantly, eukaryote and bacterial globins with a truncated 2-on-2 α-helical fold were discovered. Genomic information over the last 20 years has dramatically expanded the list of known globins, demonstrating their existence in a limited number of archaeal genomes, a majority of bacterial genomes and an overwhelming majority of eukaryote genomes. In vertebrates, 6 additional globin types were identified, namely neuroglobin (Ngb), cytoglobin (Cygb), globin E (GbE), globin X (GbX), globin Y (GbY) and androglobin (Adgb). Furthermore, functions beyond the familiar oxygen transport and storage have been discovered within the vertebrate globin family, including NO metabolism, peroxidase activity, scavenging of free radicals, and signaling functions. The extension of the knowledge on globin functions suggests that the original roles of bacterial globins must have been enzymatic, involved in defense against NO toxicity, and perhaps also as sensors of O2, regulating taxis away or towards high O2 concentrations. In this review, we aimed to discuss the evolution and remarkable functional diversity of vertebrate globins with particular focus on the variety of non-canonical expression sites of mammalian globins and their according impressive variability of atypical functions.
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Finoshin AD, Adameyko KI, Mikhailov KV, Kravchuk OI, Georgiev AA, Gornostaev NG, Kosevich IA, Mikhailov VS, Gazizova GR, Shagimardanova EI, Gusev OA, Lyupina YV. Iron metabolic pathways in the processes of sponge plasticity. PLoS One 2020; 15:e0228722. [PMID: 32084159 PMCID: PMC7034838 DOI: 10.1371/journal.pone.0228722] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 01/21/2020] [Indexed: 12/11/2022] Open
Abstract
The ability to regulate oxygen consumption evolved in ancestral animals and is intrinsically linked to iron metabolism. The iron pathways have been intensively studied in mammals, whereas data on distant invertebrates are limited. Sea sponges represent the oldest animal phylum and have unique structural plasticity and capacity to reaggregate after complete dissociation. We studied iron metabolic factors and their expression during reaggregation in the White Sea cold-water sponges Halichondria panicea and Halisarca dujardini. De novo transcriptomes were assembled using RNA-Seq data, and evolutionary trends were analyzed with bioinformatic tools. Differential expression during reaggregation was studied for H. dujardini. Enzymes of the heme biosynthesis pathway and transport globins, neuroglobin (NGB) and androglobin (ADGB), were identified in sponges. The globins mutate at higher evolutionary rates than the heme synthesis enzymes. Highly conserved iron-regulatory protein 1 (IRP1) presumably interacts with the iron-responsive elements (IREs) found in mRNAs of ferritin (FTH1) and a putative transferrin receptor NAALAD2. The reaggregation process is accompanied by increased expression of IRP1, the antiapoptotic factor BCL2, the inflammation factor NFκB (p65), FTH1 and NGB, as well as by an increase in mitochondrial density. Our data indicate a complex mechanism of iron regulation in sponge structural plasticity and help to better understand general mechanisms of morphogenetic processes in multicellular species.
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Affiliation(s)
- Alexander D. Finoshin
- N.K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Kim I. Adameyko
- N.K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Kirill V. Mikhailov
- A.N. Belozersky Institute of Physical and Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- A.A. Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia
| | - Oksana I. Kravchuk
- N.K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | | | - Nicolay G. Gornostaev
- N.K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | | | - Victor S. Mikhailov
- N.K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | | | | | - Oleg A. Gusev
- Kazan Federal University, Kazan, Russia
- KFU-RIKEN Translational Genomics Unit, RIKEN National Science Institute, Yokohama, Japan
| | - Yulia V. Lyupina
- N.K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
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12
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Distinctive structural properties of THB11, a pentacoordinate Chlamydomonas reinhardtii truncated hemoglobin with N- and C-terminal extensions. J Biol Inorg Chem 2020; 25:267-283. [PMID: 32048044 PMCID: PMC7082302 DOI: 10.1007/s00775-020-01759-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 01/14/2020] [Indexed: 12/20/2022]
Abstract
Hemoglobins (Hbs) utilize heme b as a cofactor and are found in all kingdoms of life. The current knowledge reveals an enormous variability of Hb primary sequences, resulting in topological, biochemical and physiological individuality. As Hbs appear to modulate their reactivities through specific combinations of structural features, predicting the characteristics of a given Hb is still hardly possible. The unicellular green alga Chlamydomonas reinhardtii contains 12 genes encoding diverse Hbs of the truncated lineage, several of which possess extended N- or C-termini of unknown function. Studies on some of the Chlamydomonas Hbs revealed yet unpredictable structural and biochemical variations, which, along with a different expression of their genes, suggest diverse physiological roles. Chlamydomonas thus represents a promising system to analyze the diversification of Hb structure, biochemistry and physiology. Here, we report the crystal structure, resolved to 1.75 Å, of the heme-binding domain of cyanomet THB11 (Cre16.g662750), one of the pentacoordinate algal Hbs, which offer a free Fe-coordination site in the reduced state. The overall fold of THB11 is conserved, but individual features such as a kink in helix E, a tilted heme plane and a clustering of methionine residues at a putative tunnel exit appear to be unique. Both N- and C-termini promote the formation of oligomer mixtures, and the absence of the C terminus results in reduced nitrite reduction rates. This work widens the structural and biochemical knowledge on the 2/2Hb family and suggests that the N- and C-terminal extensions of the Chlamydomonas 2/2Hbs modulate their reactivity by intermolecular interactions.
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13
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Shen D, Bisseling T. The Evolutionary Aspects of Legume Nitrogen-Fixing Nodule Symbiosis. Results Probl Cell Differ 2020; 69:387-408. [PMID: 33263880 DOI: 10.1007/978-3-030-51849-3_14] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Nitrogen-fixing root nodule symbiosis can sustain the development of the host plants under nitrogen-limiting conditions. Such symbiosis occurs only in a clade of angiosperms known as the nitrogen-fixing clade (NFC). It has long been proposed that root nodule symbiosis evolved several times (in parallel) in the NFC. Two recent phylogenomic studies compared the genomes of nodulating and related non-nodulating species across the four orders of the NFC and found that genes essential for nodule formation are lost or pseudogenized in the non-nodulating species. As these symbiosis genes are specifically involved in the symbiotic interaction, it means that the presence of pseudogenes and the loss of symbiosis genes strongly suggest that their ancestor, which still had functional genes, most likely had a symbiosis with nitrogen-fixing bacteria. These findings agree with the hypothesis that nodulation evolved once at the common ancestor of the NFC, and challenge the hypothesis of parallel evolution. In this chapter, we will cover the current understandings on actinorhizal-type and legume nodule development, and discuss the evolution of the legume nodule type.
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Affiliation(s)
- Defeng Shen
- Laboratory of Molecular Biology, Graduate School Experimental Plant Sciences, Wageningen University, Wageningen, The Netherlands
| | - Ton Bisseling
- Laboratory of Molecular Biology, Graduate School Experimental Plant Sciences, Wageningen University, Wageningen, The Netherlands.
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14
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Wang L, Rubio MC, Xin X, Zhang B, Fan Q, Wang Q, Ning G, Becana M, Duanmu D. CRISPR/Cas9 knockout of leghemoglobin genes in Lotus japonicus uncovers their synergistic roles in symbiotic nitrogen fixation. THE NEW PHYTOLOGIST 2019; 224:818-832. [PMID: 31355948 DOI: 10.1111/nph.16077] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/17/2019] [Indexed: 05/20/2023]
Abstract
Legume nodules contain high concentrations of leghemoglobins (Lbs) encoded by several genes. The reason for this multiplicity is unknown. CRISPR/Cas9 technology was used to generate stable mutants of the three Lbs of Lotus japonicus. The phenotypes were characterized at the physiological, biochemical and molecular levels. Nodules of the triple mutants were examined by electron microscopy and subjected to RNA-sequencing (RNA-seq) analysis. Complementation studies revealed that Lbs function synergistically to maintain optimal N2 fixation. The nodules of the triple mutants overproduced superoxide radicals and hydrogen peroxide, which was probably linked to activation of NADPH oxidases and changes in superoxide dismutase isoforms expression. The mutant nodules showed major ultrastructural alterations, including vacuolization, accumulation of poly-β-hydroxybutyrate and disruption of mitochondria. RNA-seq of c. 20 000 genes revealed significant changes in expression of carbon and nitrogen metabolism genes, transcription factors, and proteinases. Lb-deficient nodules had c. 30-50-fold less heme but similar transcript levels of heme biosynthetic genes, suggesting a post-translational regulatory mechanism of heme synthesis. We conclude that Lbs act additively in nodules and that the lack of Lbs results in early nodule senescence. Our observations also provide insight into the reprogramming of the gene expression network associated with Lb deficiency, probably as a result of uncontrolled intracellular free O2 concentration.
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Affiliation(s)
- Longlong Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Maria Carmen Rubio
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080, Zaragoza, Spain
| | - Xian Xin
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Baoli Zhang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Qiuling Fan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Qiang Wang
- Key Laboratory of Plant Stress Biology, State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Guogui Ning
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Manuel Becana
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080, Zaragoza, Spain
| | - Deqiang Duanmu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
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15
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Zhang J, Buegger F, Albert A, Ghirardo A, Winkler B, Schnitzler JP, Hebelstrup KH, Durner J, Lindermayr C. Phytoglobin overexpression promotes barley growth in the presence of enhanced level of atmospheric nitric oxide. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:4521-4537. [PMID: 31245808 PMCID: PMC6736386 DOI: 10.1093/jxb/erz249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 05/17/2019] [Indexed: 05/03/2023]
Abstract
To investigate the effect of high atmospheric NO concentrations on crop plants and the role of phytoglobins under these conditions, we performed a long-term study on barley 'Golden Promise' wild type (WT), class 1 phytoglobin knockdown (HvPgb1.1-) and class 1 phytoglobin overexpression (HvPgb1.1+) lines. Plants were cultivated with nitrogen-free nutrient solution during the entire growth period and were fumigated with different NO concentration (ambient, 800, 1500, and 3000 ppb). Analysis of fresh weight, stem number, chlorophyll content, and effective quantum yield of PSII showed that NO fumigation promoted plant growth and tillering significantly in the HvPgb1.1+ line. After 80 d of NO fumigation, dry matter weight, spikes number, kernel number, and plant kernel weight were significantly increased in HvPgb1.1+ plants with increasing NO concentration. In contrast, yield decreased in WT and HvPgb1.1- plants the higher the NO level. Application of atmospheric 15NO and 15NO2 demonstrated NO specificity of phytoglobins. 15N from 15NO could be detected in RNA, DNA, and proteins of barley leaves and the 15N levels were significantly higher in HvPgb1.1+ plants in comparison with HvPgb1.1- and WT plants. Our results demonstrate that overexpression of phytoglobins allows plants to more efficiently use atmospheric NO as N source.
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Affiliation(s)
- Jiangli Zhang
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Franz Buegger
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Andreas Albert
- Research Unit Environmental Simulation, Helmholtz Zentrum München, Neuherberg, Germany
| | - Andrea Ghirardo
- Research Unit Environmental Simulation, Helmholtz Zentrum München, Neuherberg, Germany
| | - Barbro Winkler
- Research Unit Environmental Simulation, Helmholtz Zentrum München, Neuherberg, Germany
| | - Jörg-Peter Schnitzler
- Research Unit Environmental Simulation, Helmholtz Zentrum München, Neuherberg, Germany
| | | | - Jörg Durner
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biochemical Plant Pathology, Technische Universität München, Freising, Germany
| | - Christian Lindermayr
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Neuherberg, Germany
- Correspondence:
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16
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Sugar beet hemoglobins: reactions with nitric oxide and nitrite reveal differential roles for nitrogen metabolism. Biochem J 2019; 476:2111-2125. [PMID: 31285352 PMCID: PMC6668756 DOI: 10.1042/bcj20190154] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/23/2019] [Accepted: 07/08/2019] [Indexed: 12/14/2022]
Abstract
In contrast with human hemoglobin (Hb) in red blood cells, plant Hbs do not transport oxygen, instead research points towards nitrogen metabolism. Using comprehensive and integrated biophysical methods we characterized three sugar beet Hbs: BvHb1.1, BvHb1.2 and BvHb2. Their affinities for oxygen, CO, and hexacoordination were determined. Their role in nitrogen metabolism was studied by assessing their ability to bind NO, to reduce nitrite (NiR, nitrite reductase), and to form nitrate (NOD, NO dioxygenase). Results show that BvHb1.2 has high NOD-like activity, in agreement with the high nitrate levels found in seeds where this protein is expressed. BvHb1.1, on the other side, is equally capable to bind NO as to form nitrate, its main role would be to protect chloroplasts from the deleterious effects of NO. Finally, the ubiquitous, reactive, and versatile BvHb2, able to adopt 'open and closed forms', would be part of metabolic pathways where the balance between oxygen and NO is essential. For all proteins, the NiR activity is relevant only when nitrite is present at high concentrations and both NO and oxygen are absent. The three proteins have distinct intrinsic capabilities to react with NO, oxygen and nitrite; however, it is their concentration which will determine the BvHbs' activity.
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17
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Gallagher MD, Macqueen DJ. Evolution and Expression of Tissue Globins in Ray-Finned Fishes. Genome Biol Evol 2018; 9:32-47. [PMID: 28173090 PMCID: PMC5381549 DOI: 10.1093/gbe/evw266] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2016] [Indexed: 12/30/2022] Open
Abstract
The globin gene family encodes oxygen-binding hemeproteins conserved across the major branches of multicellular life. The origins and evolutionary histories of complete globin repertoires have been established for many vertebrates, but there remain major knowledge gaps for ray-finned fish. Therefore, we used phylogenetic, comparative genomic and gene expression analyses to discover and characterize canonical “non-blood” globin family members (i.e., myoglobin, cytoglobin, neuroglobin, globin-X, and globin-Y) across multiple ray-finned fish lineages, revealing novel gene duplicates (paralogs) conserved from whole genome duplication (WGD) and small-scale duplication events. Our key findings were that: (1) globin-X paralogs in teleosts have been retained from the teleost-specific WGD, (2) functional paralogs of cytoglobin, neuroglobin, and globin-X, but not myoglobin, have been conserved from the salmonid-specific WGD, (3) triplicate lineage-specific myoglobin paralogs are conserved in arowanas (Osteoglossiformes), which arose by tandem duplication and diverged under positive selection, (4) globin-Y is retained in multiple early branching fish lineages that diverged before teleosts, and (5) marked variation in tissue-specific expression of globin gene repertoires exists across ray-finned fish evolution, including several previously uncharacterized sites of expression. In this respect, our data provide an interesting link between myoglobin expression and the evolution of air breathing in teleosts. Together, our findings demonstrate great-unrecognized diversity in the repertoire and expression of nonblood globins that has arisen during ray-finned fish evolution.
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Affiliation(s)
- Michael D Gallagher
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Daniel J Macqueen
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom
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18
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Shankar A, Fernandes JL, Kaur K, Sharma M, Kundu S, Pandey GK. Rice phytoglobins regulate responses under low mineral nutrients and abiotic stresses in Arabidopsis thaliana. PLANT, CELL & ENVIRONMENT 2018; 41:215-230. [PMID: 29044557 DOI: 10.1111/pce.13081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 09/25/2017] [Accepted: 09/27/2017] [Indexed: 06/07/2023]
Abstract
Just like animals, plants also contain haemoglobins (known as phytoglobins in plants). Plant phytoglobins (Pgbs) have been categorized into 6 different classes, namely, Phytogb0 (Pgb0), Phytogb1 (Pgb1), Phytogb2 (Pgb2), SymPhytogb (sPgb), Leghaemoglobin (Lb), and Phytogb3 (Pgb3). Among the 6 Phytogbs, sPgb and Lb have been functionally characterized, whereas understanding of the roles of other Pgbs is still evolving. In our present study, we have explored the function of 2 rice Pgbs (OsPgb1.1 and OsPgb1.2). OsPgb1.1, OsPgb1.2, OsPgb1.3, and OsPgb1.4 displayed increased level of transcript upon salt, drought, cold, and ABA treatment. The overexpression (OX) lines of OsPgb1.2 in Arabidopsis showed a tolerant phenotype in terms of better root growth in low potassium (K+ ) conditions. The expression of the known K+ gene markers such as LOX2, HAK5, and CAX3 was much higher in the OsPgb1.2 OX as compared to wild type. Furthermore, the OsPgb1.2 OX lines showed a decrease in reactive oxygen species (ROS) production and conversely an increase in the K+ content, both in root and shoot, as compared to wild type in K+ limiting condition. Our results indicated the potential involvement of OsPgb1.2 in signalling networks triggered by the nutrient deficiency stresses.
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Affiliation(s)
- Alka Shankar
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Joel Lars Fernandes
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Kanwaljeet Kaur
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Manisha Sharma
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Suman Kundu
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Girdhar K Pandey
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
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19
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Minaeva E, Zalutskaya Z, Filina V, Ermilova E. Truncated hemoglobin 1 is a new player in Chlamydomonas reinhardtii acclimation to sulfur deprivation. PLoS One 2017; 12:e0186851. [PMID: 29049377 PMCID: PMC5648252 DOI: 10.1371/journal.pone.0186851] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 10/09/2017] [Indexed: 12/23/2022] Open
Abstract
Truncated hemoglobins constitute a large family, present in bacteria, in archaea and in eukaryotes. However, a majority of physiological functions of these proteins remains to be elucidated. Identification and characterization of a novel role of truncated hemoglobins in the model alga provides a framework for a more complete understanding of their biological functions. Here, we use quantitative RT-PCR to show that three truncated hemoglobins of Chlamydomonas reinhardtii, THB1, THB2 and THB12, are induced under conditions of depleted sulfur (S) supply. THB1 underexpression results in the decrease in cell size, as well in levels of proteins, chlorophylls and mRNA of several S-responsive genes under S starvation. We provide evidence that knock-down of THB1 enhances NO production under S deprivation. In S-deprived cells, a subset of S limitation-responsive genes is controlled by NO in THB1-dependent pathway. Moreover, we demonstrate that deficiency for S represses the nitrate reduction and that THB1 is involved in this control. Thus, our data support the idea that in S-deprived cells THB1 plays a dual role in NO detoxification and in coordinating sulfate limitation with nitrate assimilation. This study uncovers a new function for the Chlamydomonas reinhardtii THB1 in the control of proper response to S deprivation.
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Affiliation(s)
- Ekaterina Minaeva
- Biological Faculty, Saint-Petersburg State University, Saint-Petersburg, Russia
| | - Zhanneta Zalutskaya
- Biological Faculty, Saint-Petersburg State University, Saint-Petersburg, Russia
| | - Valentina Filina
- Biological Faculty, Saint-Petersburg State University, Saint-Petersburg, Russia
| | - Elena Ermilova
- Biological Faculty, Saint-Petersburg State University, Saint-Petersburg, Russia
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20
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Butcher D, Bernad S, Derrien V, Sebban P, Miksovska J. Role of Ionic Strength and pH in Modulating Thermodynamic Profiles Associated with CO Escape from Rice Nonsymbiotic Hemoglobin 1. J Phys Chem B 2017; 121:351-364. [PMID: 28072536 DOI: 10.1021/acs.jpcb.6b06933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Type 1 nonsymbiotic hemoglobins are found in a wide variety of land plants and exhibit very high affinities for exogenous gaseous ligands. These proteins are presumed to have a role in protecting plant cells from oxidative stress under etiolated/hypoxic conditions through NO dioxygenase activity. In this study we have employed photoacoustic calorimetry, time-resolved absorption spectroscopy, and classical molecular dynamics simulations in order to elucidate thermodynamics, kinetics, and ligand migration pathways upon CO photodissociation from WT and a H73L mutant of type 1 nonsymbiotic hemoglobin from Oryza sativa (rice). We observe a temperature dependence of the resolved thermodynamic parameters for CO photodissociation from CO-rHb1 which we attribute to temperature dependent formation of a network of electrostatic interactions in the vicinity of the heme propionate groups. We also observe slower ligand escape from the protein matrix under mildly acidic conditions in both the WT and H73L mutant (τ = 134 ± 19 and 90 ± 15 ns). Visualization of transient hydrophobic channels within our classical molecular dynamics trajectories allows us to attribute this phenomenon to a change in the ligand migration pathway which occurs upon protonation of the distal His73, His117, and His152. Protonation of these residues may be relevant to the functioning of the protein in vivo given that etiolation/hypoxia can cause a decrease in intracellular pH in plant cells.
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Affiliation(s)
- David Butcher
- Department of Chemistry and Biochemistry, Florida International University , Miami Florida 33199, United States
| | - Sophie Bernad
- Laboratoire de Chimie Physique, Université Paris-Sud 11 , 91405 Orsay, France
| | - Valerie Derrien
- Laboratoire de Chimie Physique, Université Paris-Sud 11 , 91405 Orsay, France
| | - Pierre Sebban
- Laboratoire de Chimie Physique, Université Paris-Sud 11 , 91405 Orsay, France
| | - Jaroslava Miksovska
- Department of Chemistry and Biochemistry, Florida International University , Miami Florida 33199, United States.,Biomolecular Sciences Institute, Florida International University , Miami, Florida 33199, United States
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21
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Ascenzi P, di Masi A, Leboffe L, Fiocchetti M, Nuzzo MT, Brunori M, Marino M. Neuroglobin: From structure to function in health and disease. Mol Aspects Med 2016; 52:1-48. [DOI: 10.1016/j.mam.2016.10.004] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 10/27/2016] [Accepted: 10/27/2016] [Indexed: 01/01/2023]
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22
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Doyle JJ. Chasing unicorns: Nodulation origins and the paradox of novelty. AMERICAN JOURNAL OF BOTANY 2016; 103:1865-1868. [PMID: 27756731 DOI: 10.3732/ajb.1600260] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 08/31/2016] [Indexed: 05/25/2023]
Affiliation(s)
- Jeff J Doyle
- School of Integrative Plant Science, Section of Plant Breeding & Genetics and Section of Plant Biology, 240 Emerson Hall, Cornell University, Ithaca, New York 14853 USA
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23
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Mira M, Hill RD, Stasolla C. Regulation of programmed cell death by phytoglobins. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:5901-5908. [PMID: 27371712 DOI: 10.1093/jxb/erw259] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Programmed cell death (PCD) is a fundamental plant process in growth and development and in response to both biotic and abiotic stresses. Nitric oxide (NO) is a central component in determining whether a cell undergoes PCD, either as a direct elicitor of the response or as a factor in signal transduction from various hormones. Both NO and hormones that use NO as a signal transducer are mobile in the plant. Why do one set of cells die while adjacent cells remain alive, if this is the case? There is evidence to suggest that phytoglobins (Pgbs; previously termed non-symbiotic hemoglobins) may act as binary switches to determine plant cellular responses to perturbations. There are anywhere from one to five Pgb genes in plants that are expressed in response to growth and development and to stress. One of their main functions is to scavenge NO. This review will discuss how Pgb modulates cellular responses to auxin, cytokinin, and jasmonic acid during growth and development and in response to stress. The moderation in the production of reactive oxygen species (ROS) by Pgbs and the effects on PCD will also be discussed. An overall mechanism for Pgb involvement will be presented.
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Affiliation(s)
- Mohammed Mira
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
- Department of Botany, Faculty of Science, Tanta University, Tanta 31527, Egypt
| | - Robert D Hill
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Claudio Stasolla
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
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Abstract
If life without heme-Fe were at all possible, it would definitely be different. Indeed this complex and versatile iron-porphyrin macrocycle upon binding to different “globins” yields hemeproteins crucial to sustain a variety of vital functions, generally classified, for convenience, in a limited number of functional families. Over-and-above the array of functions briefly outlined below, the spectacular progress in molecular genetics seen over the last 30 years led to the discovery of many hitherto unknown novel hemeproteins in prokaryotes and eukaryotes. Here, we highlight a few basic aspects of the chemistry of the hemeprotein universe, in particular those that are relevant to the control of heme-Fe reactivity and specialization, as sculpted by a variety of interactions with the protein moiety.
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Affiliation(s)
- Paolo Ascenzi
- Dipartimento di Scienze, Università Roma Tre, Viale Marconi 446, I-00146 Roma, Italy
| | - Maurizio Brunori
- Dipartimento di Scienze Biochimiche “Alessandro Rossi Fanelli” and Istituto Pasteur — Fondazione Cenci, Bolognetti, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
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Abstract
Somatic embryogenesis involves a broad repertoire of genes, and complex expression patterns controlled by a concerted gene regulatory network. The present work describes this regulatory network focusing on the main aspects involved, with the aim of providing a deeper insight into understanding the total reprogramming of cells into a new organism through a somatic way. To the aim, the chromatin remodeling necessary to totipotent stem cell establishment is described, as the activity of numerous transcription factors necessary to cellular totipotency reprogramming. The eliciting effects of various plant growth regulators on the induction of somatic embryogenesis is also described and put in relation with the activity of specific transcription factors. The role of programmed cell death in the process, and the related function of specific hemoglobins as anti-stress and anti-death compounds is also described. The tools for biotechnology coming from this information is highlighted in the concluding remarks.
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26
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Sanz-Luque E, Chamizo-Ampudia A, Llamas A, Galvan A, Fernandez E. Understanding nitrate assimilation and its regulation in microalgae. FRONTIERS IN PLANT SCIENCE 2015; 6:899. [PMID: 26579149 PMCID: PMC4620153 DOI: 10.3389/fpls.2015.00899] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/09/2015] [Indexed: 05/02/2023]
Abstract
Nitrate assimilation is a key process for nitrogen (N) acquisition in green microalgae. Among Chlorophyte algae, Chlamydomonas reinhardtii has resulted to be a good model system to unravel important facts of this process, and has provided important insights for agriculturally relevant plants. In this work, the recent findings on nitrate transport, nitrate reduction and the regulation of nitrate assimilation are presented in this and several other algae. Latest data have shown nitric oxide (NO) as an important signal molecule in the transcriptional and posttranslational regulation of nitrate reductase and inorganic N transport. Participation of regulatory genes and proteins in positive and negative signaling of the pathway and the mechanisms involved in the regulation of nitrate assimilation, as well as those involved in Molybdenum cofactor synthesis required to nitrate assimilation, are critically reviewed.
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Affiliation(s)
| | | | | | | | - Emilio Fernandez
- Department of Biochemistry and Molecular Biology, University of CordobaCordoba, Spain
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27
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Abstract
Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice (
Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the
nshb genes, consisting of
hb1,
hb2,
hb3,
hb4 and
hb5, and a single copy of the
thb gene exist in
Oryza sativa var. indica and
O.
sativa var. japonica, Hb transcripts coexist in rice organs and Hb polypeptides exist in rice embryonic and vegetative organs and in the cytoplasm of differentiating cells. At the structural level, the crystal structure of rice Hb1 has been elucidated, and the structures of the other rice Hbs have been modeled. Kinetic analysis indicated that rice Hb1 and 2, and possibly rice Hb3 and 4, exhibit a very high affinity for O
2, whereas rice Hb5 and tHb possibly exhibit a low to moderate affinity for O
2. Based on the accumulated information on the properties of rice Hbs and data from the analysis of other plant and non-plant Hbs, it is likely that Hbs play a variety of roles in rice organs, including O
2-transport, O
2-sensing, NO-scavenging and redox-signaling. From an evolutionary perspective, an outline for the evolution of rice Hbs is available. Rice
nshb and
thb genes vertically evolved through different lineages, rice nsHbs evolved into clade I and clade II lineages and rice
nshbs and
thbs evolved under the effect of neutral selection. This review also reveals lacunae in our ability to completely understand rice Hbs. Primary lacunae are the absence of experimental information about the precise functions of rice Hbs, the properties of modeled rice Hbs and the
cis-elements and
trans-acting factors that regulate the expression of rice
hb genes, and the partial understanding of the evolution of rice Hbs.
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Affiliation(s)
- Raúl Arredondo-Peter
- Laboratorio de Biofísica y Biología Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, 62210, Mexico
| | - Jose F Moran
- Instituto de Agrobiotecnología, IdAB-CSIC-Universidad Pública de Navarra-Gobierno de Navarra, Navarre, E-31192, Spain
| | - Gautam Sarath
- Grain, Forage and Bioenergy Research Unit, USDA-ARS, University of Nebraska-Lincoln, Lincoln, NE, 68583-0937, USA
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28
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Abstract
In the last few years, advances in algal research have identified the participation of haemoglobins in nitrogen metabolism and the management of reactive nitrogen and oxygen species. This chapter summarises the state of knowledge concerning algal haemoglobins with a focus on the most widely used model system, namely, Chlamydomonas reinhardtii. Genetic, physiologic, structural, and chemical information is compiled to provide a framework for further studies.
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Affiliation(s)
- Eric A Johnson
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Juliette T J Lecomte
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA.
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29
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Herman JL, Challis CJ, Novák Á, Hein J, Schmidler SC. Simultaneous Bayesian estimation of alignment and phylogeny under a joint model of protein sequence and structure. Mol Biol Evol 2014; 31:2251-66. [PMID: 24899668 PMCID: PMC4137710 DOI: 10.1093/molbev/msu184] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
For sequences that are highly divergent, there is often insufficient information to infer accurate alignments, and phylogenetic uncertainty may be high. One way to address this issue is to make use of protein structural information, since structures generally diverge more slowly than sequences. In this work, we extend a recently developed stochastic model of pairwise structural evolution to multiple structures on a tree, analytically integrating over ancestral structures to permit efficient likelihood computations under the resulting joint sequence-structure model. We observe that the inclusion of structural information significantly reduces alignment and topology uncertainty, and reduces the number of topology and alignment errors in cases where the true trees and alignments are known. In some cases, the inclusion of structure results in changes to the consensus topology, indicating that structure may contain additional information beyond that which can be obtained from sequences. We use the model to investigate the order of divergence of cytoglobins, myoglobins, and hemoglobins and observe a stabilization of phylogenetic inference: although a sequence-based inference assigns significant posterior probability to several different topologies, the structural model strongly favors one of these over the others and is more robust to the choice of data set.
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Affiliation(s)
- Joseph L Herman
- Department of Statistics, University of Oxford, Oxford, United KingdomDivision of Mathematical Biology, National Institute of Medical Research, London, United Kingdom
| | | | - Ádám Novák
- Department of Statistics, University of Oxford, Oxford, United Kingdom
| | - Jotun Hein
- Department of Statistics, University of Oxford, Oxford, United Kingdom
| | - Scott C Schmidler
- Department of Statistical Science, Duke UniversityDepartment of Computer Science, Duke University
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30
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Johnson EA, Rice S, Preimesberger MR, Nye DB, Gilevicius L, Wenke BB, Brown JM, Witman GB, Lecomte JTJ. Characterization of THB1, a Chlamydomonas reinhardtii truncated hemoglobin: linkage to nitrogen metabolism and identification of lysine as the distal heme ligand. Biochemistry 2014; 53:4573-89. [PMID: 24964018 PMCID: PMC4108185 DOI: 10.1021/bi5005206] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 06/23/2014] [Indexed: 12/21/2022]
Abstract
The nuclear genome of the model organism Chlamydomonas reinhardtii contains genes for a dozen hemoglobins of the truncated lineage. Of those, THB1 is known to be expressed, but the product and its function have not yet been characterized. We present mutagenesis, optical, and nuclear magnetic resonance data for the recombinant protein and show that at pH near neutral in the absence of added ligand, THB1 coordinates the heme iron with the canonical proximal histidine and a distal lysine. In the cyanomet state, THB1 is structurally similar to other known truncated hemoglobins, particularly the heme domain of Chlamydomonas eugametos LI637, a light-induced chloroplastic hemoglobin. Recombinant THB1 is capable of binding nitric oxide (NO(•)) in either the ferric or ferrous state and has efficient NO(•) dioxygenase activity. By using different C. reinhardtii strains and growth conditions, we demonstrate that the expression of THB1 is under the control of the NIT2 regulatory gene and that the hemoglobin is linked to the nitrogen assimilation pathway.
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Affiliation(s)
- Eric A. Johnson
- Department
of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Selena
L. Rice
- Department
of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | | | - Dillon B. Nye
- Department
of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Lukas Gilevicius
- Department
of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Belinda B. Wenke
- Department
of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jason M. Brown
- Department
of Cell and Developmental Biology, University
of Massachusetts Medical School, Worcester, Massachusetts 01655, United States
| | - George B. Witman
- Department
of Cell and Developmental Biology, University
of Massachusetts Medical School, Worcester, Massachusetts 01655, United States
| | - Juliette T. J. Lecomte
- Department
of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
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31
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Burmester T, Hankeln T. Function and evolution of vertebrate globins. Acta Physiol (Oxf) 2014; 211:501-14. [PMID: 24811692 DOI: 10.1111/apha.12312] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 04/17/2014] [Accepted: 04/30/2014] [Indexed: 02/06/2023]
Abstract
Globins are haem-proteins that bind O2 and thus play an important role in the animal's respiration and oxidative energy production. However, globins may also have other functions such as the decomposition or production of NO, the detoxification of reactive oxygen species or intracellular signalling. In addition to the well-investigated haemoglobins and myoglobins, genome sequence analyses have led to the identification of six further globin types in vertebrates: androglobin, cytoglobin, globin E, globin X, globin Y and neuroglobin. Here, we review the present state of knowledge on the functions, the taxonomic distribution and evolution of vertebrate globins, drawing conclusions about the functional changes underlying present-day globin diversity.
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Affiliation(s)
- T. Burmester
- Institute of Zoology and Zoological Museum; University of Hamburg; Hamburg Germany
| | - T. Hankeln
- Institute of Molecular Genetics; Johannes Gutenberg-University Mainz; Mainz Germany
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32
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Dröge J, Buczek D, Suzuki Y, Makałowski W. Amoebozoa possess lineage-specific globin gene repertoires gained by individual horizontal gene transfers. Int J Biol Sci 2014; 10:689-701. [PMID: 25013378 PMCID: PMC4081604 DOI: 10.7150/ijbs.8327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/24/2014] [Indexed: 12/13/2022] Open
Abstract
The Amoebozoa represent a clade of unicellular amoeboid organisms that display a wide variety of lifestyles, including free-living and parasitic species. For example, the social amoeba Dictyostelium discoideum has the ability to aggregate into a multicellular fruiting body upon starvation, while the pathogenic amoeba Entamoeba histolytica is a parasite of humans. Globins are small heme proteins that are present in almost all extant organisms. Although several genomes of amoebozoan species have been sequenced, little is known about the phyletic distribution of globin genes within this phylum. Only two flavohemoglobins (FHbs) of D. discoideum have been reported and characterized previously while the genomes of Entamoeba species are apparently devoid of globin genes. We investigated eleven amoebozoan species for the presence of globin genes by genomic and phylogenetic in silico analyses. Additional FHb genes were identified in the genomes of four social amoebas and the true slime mold Physarum polycephalum. Moreover, a single-domain globin (SDFgb) of Hartmannella vermiformis, as well as two truncated hemoglobins (trHbs) of Acanthamoeba castellanii were identified. Phylogenetic evidence suggests that these globin genes were independently acquired via horizontal gene transfer from some ancestral bacteria. Furthermore, the phylogenetic tree of amoebozoan FHbs indicates that they do not share a common ancestry and that a transfer of FHbs from bacteria to amoeba occurred multiple times.
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Affiliation(s)
- Jasmin Dröge
- 1. Institute of Bioinformatics, Faculty of Medicine, University of Muenster, Niels Stensen Str. 14, 48149 Muenster, Germany
| | - Dorota Buczek
- 1. Institute of Bioinformatics, Faculty of Medicine, University of Muenster, Niels Stensen Str. 14, 48149 Muenster, Germany ; 2. Institute of Molecular Biology and Biotechnology, A. Mickiewicz University, Poznan, Poland
| | - Yutaka Suzuki
- 3. Department of Medical Genomic Sciences, University of Tokyo, Tokyo, Japan
| | - Wojciech Makałowski
- 1. Institute of Bioinformatics, Faculty of Medicine, University of Muenster, Niels Stensen Str. 14, 48149 Muenster, Germany ; 3. Department of Medical Genomic Sciences, University of Tokyo, Tokyo, Japan
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Huang S, Hill RD, Wally OSD, Dionisio G, Ayele BT, Jami SK, Stasolla C. Hemoglobin Control of Cell Survival/Death Decision Regulates in Vitro Plant Embryogenesis. PLANT PHYSIOLOGY 2014; 165:810-825. [PMID: 24784758 PMCID: PMC4044835 DOI: 10.1104/pp.114.239335] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 04/22/2014] [Indexed: 05/19/2023]
Abstract
Programmed cell death (PCD) in multicellular organisms is a vital process in growth, development, and stress responses that contributes to the formation of tissues and organs. Although numerous studies have defined the molecular participants in apoptotic and PCD cascades, successful identification of early master regulators that target specific cells to live or die is limited. Using Zea mays somatic embryogenesis as a model system, we report that the expressions of two plant hemoglobin (Hb) genes (ZmHb1 and ZmHb2) regulate the cell survival/death decision that influences somatic embryogenesis through their cell-specific localization patterns. Suppression of either of the two ZmHbs is sufficient to induce PCD through a pathway initiated by elevated NO and Zn2+ levels and mediated by production of reactive oxygen species. The effect of the death program on the fate of the developing embryos is dependent on the localization patterns of the two ZmHbs. During somatic embryogenesis, ZmHb2 transcripts are restricted to a few cells anchoring the embryos to the subtending embryogenic tissue, whereas ZmHb1 transcripts extend to several embryonic domains. Suppression of ZmHb2 induces PCD in the anchoring cells, allowing the embryos to develop further, whereas suppression of ZmHb1 results in massive PCD, leading to abortion. We conclude that regulation of the expression of these ZmHbs has the capability to determine the developmental fate of the embryogenic tissue during somatic embryogenesis through their effect on PCD. This unique regulation might have implications for development and differentiation in other species.
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Affiliation(s)
- Shuanglong Huang
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (S.H., R.D.H., O.S.D.W., B.T.A., S.K.J., C.S.); andDepartment of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University-Flakkebjerg, 4200 Slagelse, Denmark (G.D.)
| | - Robert D Hill
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (S.H., R.D.H., O.S.D.W., B.T.A., S.K.J., C.S.); andDepartment of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University-Flakkebjerg, 4200 Slagelse, Denmark (G.D.)
| | - Owen S D Wally
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (S.H., R.D.H., O.S.D.W., B.T.A., S.K.J., C.S.); andDepartment of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University-Flakkebjerg, 4200 Slagelse, Denmark (G.D.)
| | - Giuseppe Dionisio
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (S.H., R.D.H., O.S.D.W., B.T.A., S.K.J., C.S.); andDepartment of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University-Flakkebjerg, 4200 Slagelse, Denmark (G.D.)
| | - Belay T Ayele
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (S.H., R.D.H., O.S.D.W., B.T.A., S.K.J., C.S.); andDepartment of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University-Flakkebjerg, 4200 Slagelse, Denmark (G.D.)
| | - Sravan Kumar Jami
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (S.H., R.D.H., O.S.D.W., B.T.A., S.K.J., C.S.); andDepartment of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University-Flakkebjerg, 4200 Slagelse, Denmark (G.D.)
| | - Claudio Stasolla
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (S.H., R.D.H., O.S.D.W., B.T.A., S.K.J., C.S.); andDepartment of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University-Flakkebjerg, 4200 Slagelse, Denmark (G.D.)
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Leiva-Eriksson N, Pin PA, Kraft T, Dohm JC, Minoche AE, Himmelbauer H, Bülow L. Differential expression patterns of non-symbiotic hemoglobins in sugar beet (Beta vulgaris ssp. vulgaris). PLANT & CELL PHYSIOLOGY 2014; 55:834-44. [PMID: 24486763 DOI: 10.1093/pcp/pcu027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Biennial sugar beet (Beta vulgaris spp. vulgaris) is a Caryophyllidae that has adapted its growth cycle to the seasonal temperature and daylength variation of temperate regions. This is the first time a holistic study of the expression pattern of non-symbiotic hemoglobins (nsHbs) is being carried out in a member of this group and under two essential environmental conditions for flowering, namely vernalization and length of photoperiod. BvHb genes were identified by sequence homology searches against the latest draft of the sugar beet genome. Three nsHb genes (BvHb1.1, BvHb1.2 and BvHb2) and one truncated Hb gene (BvHb3) were found in the genome of sugar beet. Gene expression profiling of the nsHb genes was carried out by quantitative PCR in different organs and developmental stages, as well as during vernalization and under different photoperiods. BvHb1.1 and BvHb2 showed differential expression during vernalization as well as during long and short days. The high expression of BvHb2 indicates that it has an active role in the cell, maybe even taking over some BvHb1.2 functions, except during germination where BvHb1.2 together with BvHb1.1-both Class 1 nsHbs-are highly expressed. The unprecedented finding of a leader peptide at the N-terminus of BvHb1.1, for the first time in an nsHb from higher plants, together with its observed expression indicate that it may have a very specific role due to its suggested location in chloroplasts. Our findings open up new possibilities for research, breeding and engineering since Hbs could be more involved in plant development than previously was anticipated.
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Affiliation(s)
- Nélida Leiva-Eriksson
- Department of Pure and Applied Biochemistry, Lund University, Box 124, 221.00 Lund, Sweden
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35
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Dumont E, Jokipii-Lukkari S, Parkash V, Vuosku J, Sundström R, Nymalm Y, Sutela S, Taskinen K, Kallio PT, Salminen TA, Häggman H. Evolution, three-dimensional model and localization of truncated hemoglobin PttTrHb of hybrid aspen. PLoS One 2014; 9:e88573. [PMID: 24520401 PMCID: PMC3919811 DOI: 10.1371/journal.pone.0088573] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 01/09/2014] [Indexed: 11/19/2022] Open
Abstract
Thus far, research on plant hemoglobins (Hbs) has mainly concentrated on symbiotic and non-symbiotic Hbs, and information on truncated Hbs (TrHbs) is scarce. The aim of this study was to examine the origin, structure and localization of the truncated Hb (PttTrHb) of hybrid aspen (Populus tremula L. × tremuloides Michx.), the model system of tree biology. Additionally, we studied the PttTrHb expression in relation to non-symbiotic class1 Hb gene (PttHb1) using RNAi-silenced hybrid aspen lines. Both the phylogenetic analysis and the three-dimensional (3D) model of PttTrHb supported the view that plant TrHbs evolved vertically from a bacterial TrHb. The 3D model suggested that PttTrHb adopts a 2-on-2 sandwich of α-helices and has a Bacillus subtilis -like ligand-binding pocket in which E11Gln and B10Tyr form hydrogen bonds to a ligand. However, due to differences in tunnel cavity and gate residue (E7Ala), it might not show similar ligand-binding kinetics as in Bs-HbO (E7Thr). The immunolocalization showed that PttTrHb protein was present in roots, stems as well as leaves of in vitro -grown hybrid aspens. In mature organs, PttTrHb was predominantly found in the vascular bundles and specifically at the site of lateral root formation, overlapping consistently with areas of nitric oxide (NO) production in plants. Furthermore, the NO donor sodium nitroprusside treatment increased the amount of PttTrHb in stems. The observed PttTrHb localization suggests that PttTrHb plays a role in the NO metabolism.
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Affiliation(s)
- Estelle Dumont
- Department of Biology, University of Oulu, Oulu, Finland
- UMR-MD1, Transporteurs Membranaires, Chimiorésistance et Drug-Design, Aix-Marseille Université, Marseille, France
| | | | - Vimal Parkash
- Structural Bioinformatics Laboratory, Department of Biosciences, Åbo Akademi University, Turku, Finland
| | - Jaana Vuosku
- Department of Biology, University of Oulu, Oulu, Finland
| | - Robin Sundström
- Structural Bioinformatics Laboratory, Department of Biosciences, Åbo Akademi University, Turku, Finland
| | - Yvonne Nymalm
- Structural Bioinformatics Laboratory, Department of Biosciences, Åbo Akademi University, Turku, Finland
| | - Suvi Sutela
- Department of Biology, University of Oulu, Oulu, Finland
| | | | | | - Tiina A. Salminen
- Structural Bioinformatics Laboratory, Department of Biosciences, Åbo Akademi University, Turku, Finland
| | - Hely Häggman
- Department of Biology, University of Oulu, Oulu, Finland
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36
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Igamberdiev AU, Stasolla C, Hill RD. Low Oxygen Stress, Nonsymbiotic Hemoglobins, NO, and Programmed Cell Death. LOW-OXYGEN STRESS IN PLANTS 2014. [DOI: 10.1007/978-3-7091-1254-0_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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37
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Sutela S, Ylioja T, Jokipii-Lukkari S, Anttila AK, Julkunen-Tiitto R, Niemi K, Mölläri T, Kallio PT, Häggman H. The responses of Vitreoscilla hemoglobin-expressing hybrid aspen (Populus tremula × tremuloides) exposed to 24-h herbivory: expression of hemoglobin and stress-related genes in exposed and nonorthostichous leaves. JOURNAL OF PLANT RESEARCH 2013; 126:795-809. [PMID: 23744275 DOI: 10.1007/s10265-013-0569-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Accepted: 04/17/2013] [Indexed: 06/02/2023]
Abstract
The responses of transcriptome and phenolic compounds were determined with Populus tremula L. × Populus tremuloides Michx. expressing the hemoglobin (Hb) of Vitreoscilla (VHb) and non-transformant (wt) line. After 24-h exposure of leaves to Conistra vaccinii L., the transcript levels of endogenous non-symbiotic class 1 Hb (PttHb1) and truncated Hb (PttTrHb) genes were modestly reduced and increased, respectively, in both wt and VHb-expressing line. Besides the herbivory exposed leaves showing the most significant transcriptome changes, alterations were also detected in the transcriptome of nonorthostichous leaves positioned directly above the exposed leaves. Both wt and VHb-expressing line displayed similar herbivory-induced effects on gene expression, although the extent of responses was more pronounced in the wt than in the VHb-expressing line. The contents of phenolic compounds were not altered due to herbivory and they were alike in the wt and VHb-expressing line. In addition, we determined the relative growth rates (RGRs) of Orthosia gothica L., Ectropis crepuscularia Denis & Schiff. and Orgyia antiqua L. larvae, and found no variation in the RGRs between the lines. Thus, VHb-expressing P. tremula × tremuloides lines showed to be comparable with wt in regards to the food quality of leaves.
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Affiliation(s)
- Suvi Sutela
- Department of Biology, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland,
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38
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Rodríguez-Alonso G, Arredondo-Peter R. Variability of non-symbiotic and truncated hemoglobin genes from the genome of cultivated monocots. Commun Integr Biol 2013; 6:e27496. [PMID: 24563718 PMCID: PMC3923788 DOI: 10.4161/cib.27496] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 12/12/2013] [Indexed: 11/19/2022] Open
Abstract
Non-symbiotic (nsHb) and truncated (tHb) hemoglobins (Hbs) have been detected in a variety of land plants. The evolution of land plant nsHbs and tHbs at the protein level is well documented; however, little is known about the evolution of genes coding for these proteins. For example, the variability of the land plant nshb and thb genes is not known. Here, we report the variability of the nshb and thb genes from the genome of the cultivated monocots Brachypodium distachyon, Hordeum vulgare (barley), Oryza glaberrima (rice), O. rufipogon (rice), O. sativa (rice) var indica, O. sativa (rice) var japonica, Panicum virgatum (switchgrass), Setaria italica (foxtail millet), Sorghum bicolor (sorghum), Triticum aestivum (wheat), and Zea mays ssp. mays (maize) using sequence comparison and computational methods. Our results revealed that in cultivated monocots variability is higher in nshbs than in thbs, and suggest that major substitution events that occurred during the evolution of the cultivated monocot hbs were A→G and T→C transitions and that these genes evolved under the effect of neutral selection.
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Affiliation(s)
- Gustavo Rodríguez-Alonso
- Laboratorio de Biofísica y Biología Molecular; Departamento de Bioquímica y Biología Molecular; Facultad de Ciencias; Universidad Autónoma del Estado de Morelos; Cuernavaca, Morelos, México
| | - Raúl Arredondo-Peter
- Laboratorio de Biofísica y Biología Molecular; Departamento de Bioquímica y Biología Molecular; Facultad de Ciencias; Universidad Autónoma del Estado de Morelos; Cuernavaca, Morelos, México
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Hill RD, Huang S, Stasolla C. Hemoglobins, programmed cell death and somatic embryogenesis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2013; 211:35-41. [PMID: 23987809 DOI: 10.1016/j.plantsci.2013.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/16/2013] [Accepted: 06/17/2013] [Indexed: 05/04/2023]
Abstract
Programmed cell death (PCD) is a universal process in all multicellular organisms. It is a critical component in a diverse number of processes ranging from growth and differentiation to response to stress. Somatic embryogenesis is one such process where PCD is significantly involved. Nitric oxide is increasingly being recognized as playing a significant role in regulating PCD in both mammalian and plant systems. Plant hemoglobins scavenge NO, and evidence is accumulating that events that modify NO levels in plants also affect hemoglobin expression. Here, we review the process of PCD, describing the involvement of NO and plant hemoglobins in the process. NO is an effector of cell death in both plants and vertebrates, triggering the cascade of events leading to targeted cell death that is a part of an organism's response to stress or to tissue differentiation and development. Expression of specific hemoglobins can alter this response in plants by scavenging the NO, thus, interrupting the death process. Somatic embryogenesis is used as a model system to demonstrate how cell-specific expression of different classes of hemoglobins can alter the embryogenic process, affecting hormone synthesis, cell metabolite levels and genes associated with PCD and embryogenic competence. We propose that plant hemoglobins influence somatic embryogenesis and PCD through cell-specific expression of a distinct plant hemoglobin. It is based on the premise that both embryogenic competence and PCD are strongly influenced by cellular NO levels. Increases in cellular NO levels result in elevated Zn(2+) and reactive-oxygen species associated with PCD, but they also result in decreased expression of MYC2, a transcription factor that is a negative effector of indoleacetic acid synthesis, a hormone that positively influences embryogenic competence. Cell-specific hemoglobin expression reduces NO levels as a result of NO scavenging, resulting in cell survival.
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Affiliation(s)
- Robert D Hill
- Department of Plant Science, University of Manitoba, Winnipeg, MB, Canada.
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Hypoxic survival requires a 2-on-2 hemoglobin in a process involving nitric oxide. Proc Natl Acad Sci U S A 2013; 110:10854-9. [PMID: 23754374 DOI: 10.1073/pnas.1302592110] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hemoglobins are recognized today as a diverse family of proteins present in all kingdoms of life and performing multiple reactions beyond O2 chemistry. The physiological roles of most hemoglobins remain elusive. Here, we show that a 2-on-2 ("truncated") hemoglobin, termed THB8, is required for hypoxic growth and the expression of anaerobic genes in Chlamydomonas reinhardtii. THB8 is 1 of 12 2-on-2 hemoglobins in this species. It belongs to a subclass within the 2-on-2 hemoglobin class I family whose members feature a remarkable variety of domain arrangements and lengths. Posttranscriptional silencing of the THB8 gene results in the mis-regulation of several genes and a growth defect under hypoxic conditions. The latter is intensified in the presence of an NO scavenger, which also impairs growth of wild-type cells. As recombinant THB8 furthermore reacts with NO, the results of this study indicate that THB8 is part of an NO-dependent signaling pathway.
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Mukhi N, Dhindwal S, Uppal S, Kumar P, Kaur J, Kundu S. X-ray crystallographic structural characteristics of Arabidopsis hemoglobin I and their functional implications. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1944-56. [PMID: 23485912 DOI: 10.1016/j.bbapap.2013.02.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/16/2013] [Accepted: 02/19/2013] [Indexed: 11/24/2022]
Abstract
Genome of the model dicot flowering plant, Arabidopsis thaliana, a popular tool for understanding molecular biology of plant physiology, encodes all three classes of plant hemoglobins that differ in their sequence, ligand binding and spectral properties. As such these globins are of considerable attention. Crystal structures of few members of plant class I nonsymbiotic hemoglobin have been described earlier. Here we report the crystal structure of Arabidopsis class I hemoglobin (AHb1) to 2.2Ǻ and compare its key features with the structures of similar nonsymbiotic hemoglobin from other species. Crystal structure of AHb1 is homologous to the related members with similar globin fold and heme pocket architecture. The structure is homodimeric in the asymmetric unit with both distal and proximal histidines coordinating to the heme iron atom. Residues lining the dimeric interface are also conserved in AHb1 with the exception of additional electrostatic interaction between H112 and E113 of each subunit and that involving Y119 through two water molecules. In addition, differences in heme pocket non-covalent interactions, a novel Ser residue at F7 position, Xe binding site variability, internal cavity topology differences, CD loop conformation and stability and other such properties might explain kinetic variability in AHb1. Detailed cavity analysis of AHb1 showed the presence of a novel long tunnel connecting the distal pockets of both the monomers. Presence of such tunnel, along with conformational heterogeneity observed in the two chains, might suggest cooperative ligand binding and support its role in NO scavenging. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins.
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Affiliation(s)
- Nitika Mukhi
- Department of Genetics, University of Delhi South Campus, New Delhi, India
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Vázquez-Limón C, Castro-Bustos S, Arredondo-Peter R. Spectroscopic analysis of moss (Ceratodon purpureus and Physcomitrella patens) recombinant non-symbiotic hemoglobins. Commun Integr Biol 2013; 5:527-30. [PMID: 23336017 PMCID: PMC3541314 DOI: 10.4161/cib.21473] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Non-symbiotic hemoglobins (nsHbs) are O2-binding proteins widely distributed in land plants, including primitive bryophytes. Little is known about the properties of bryophyte nsHbs. Here, we report the spectroscopic characterization of two moss recombinant nsHbs, CerpurnsHb of Ceratodon purpureus and PhypatnsHb of Physcomitrella patens. Spectra showed that the absorption maxima of the ferrous and ferric forms of recombinant CerpurnsHb are located at 418, 531 and 557 nm and 407, 537, 569 (shoulder) and 632 (shoulder) nm, respectively, and of PhypatnsHb are located at 422, 529 and 557 nm and 407, 531, 571 (shoulder) and 647 (shoulder) nm, respectively. These absorption maxima are similar to those of rice Hb1. Also, the absorption maxima of the oxygenated ferrous form of recombinant CerpurnsHb and PhypatnsHb are located at 412, 541 and 575 nm and 414, 541 and 574 nm, respectively, similar to those of oxygenated rice Hb1 and cowpea leghemoglobin II. This evidence indicates that CerpurnsHb and PhypatnsHb are mostly hexacoordinate and that they bind O2.
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Affiliation(s)
- Consuelo Vázquez-Limón
- Laboratorio de Biofísica y Biología Molecular; Departamento de Bioquímica y Biología Molecular; Facultad de Ciencias; Universidad Autónoma del Estado de Morelos; Cuernavaca, Morelos México
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Abstract
Approximately, 20 years ago, a haemoglobin gene was identified within the genome of the cyanobacterium Nostoc commune. Haemoglobins have now been confirmed in multiple species of photosynthetic microbes beyond N. commune, and the diversity of these proteins has recently come under increased scrutiny. This chapter summarizes the state of knowledge concerning the phylogeny, physiology and chemistry of globins in cyanobacteria and green algae. Sequence information is by far the best developed and the most rapidly expanding aspect of the field. Structural and ligand-binding properties have been described for just a few proteins. Physiological data are available for even fewer. Although activities such as nitric oxide dioxygenation and oxygen scavenging are strong candidates for cellular function, dedicated studies will be required to complete the story on this intriguing and ancient group of proteins.
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