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Sun L, Wang L, Zheng Z, Liu D. Identification and characterization of an Arabidopsis phosphate starvation-induced secreted acid phosphatase as a vegetative storage protein. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 277:278-284. [PMID: 30466593 DOI: 10.1016/j.plantsci.2018.09.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 09/17/2018] [Accepted: 09/21/2018] [Indexed: 06/09/2023]
Abstract
Induction and secretion of acid phosphatases is an adaptive response of plants to phosphate starvation. The secreted acid phosphatases are believed to scavenge phosphate from organophosphate compounds in the rhizosphere, thereby increasing phosphate availability for plant absorption. To date, however, all of the characterized phosphate starvation-induced secreted acid phosphatases in plants belong to a unique acid phosphatases subfamily, called purple acid phosphatase. In this work, we identified a phosphate starvation-induced secreted acid phosphatase in Arabidopsis as a vegetative storage protein, AtVSP3. AtVSP3 exists as a monomer with molecular weight of 29 kDa. The activity of recombinant AtVSP3 protein is activated by Mg2+, Co2+, and Ca2+. AtVSP3 has an optimal pH of 6.5 for its APase activity and is relatively thermostable. The transcription of AtVSP3 is induced in roots by phosphate starvation, and the accumulation of AtVSP3 protein is high in roots and siliques. Additional research is needed to determine the function of AtVSP3 in plant responses to stress conditions.
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Affiliation(s)
- Lichao Sun
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Liangsheng Wang
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Zai Zheng
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Dong Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, People's Republic of China.
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2
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Sharma M, Gupta SK, Majumder B, Maurya VK, Deeba F, Alam A, Pandey V. Proteomics unravel the regulating role of salicylic acid in soybean under yield limiting drought stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 130:529-541. [PMID: 30098585 DOI: 10.1016/j.plaphy.2018.08.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/01/2018] [Accepted: 08/01/2018] [Indexed: 05/23/2023]
Abstract
Drought is a major concern for sustainable yield under changing environment. Soybean, an economically important oil and protein crop, is prone to drought resulting in yield instability. Salicylic acid (SA), a multifaceted growth hormone, modulates a series of parallel processes to confer drought tolerance thereby relieving yield limitations. The present study was performed in soybean plants treated with SA (0.5 mM) through seed pretreatment under drought regimes: severe stress (50% RWC) and moderate stress (75% RWC), and rehydration. Differential leaf proteome profiling with morphological, physiological and antioxidative metabolism studies were performed at two developmental stages (vegetative and flowering). This explained the tolerance attribution to soybean throughout the development attaining yield stability. Abundance of proteins involved in photosynthesis and ATP synthesis generated energy driving metabolic processes towards plant growth, development and stress acclimation. Carbon (C) metabolism proteins involved in growth, osmoregulation and C partition relieved drought-induced C impairment under SA. Defensive mechanisms against redox imbalance and protein misfolding and degradation under stress were enhanced as depicted by the abundance of proteins involved in redox balance and protein synthesis, assembly and degradation at vegetative stage. Redox signaling in chloroplast and its interplay with SA signaling triggered different defense responses as shown through thioredoxin protein abundance. Amino acid metabolism proteins abundance resulted in increased osmoprotectants accumulation like proline at initial stage which contributed later towards N (nitrogen) remobilization to developing sink. At later stage, abundance of these proteins maintained redox homeostasis and N remobilization for improved sink strength. The redox homeostasis was supported by the increased antioxidative metabolism in SA treated plants. The downregulation of proteins at flowering also contributed towards N remobilization. Yield potential was improved by SA under drought through acclimation with enhanced N and C remobilization to sink as demonstrated by increased yield parameters like seed number and weight per plant, thousand seed weight and harvest index. The potential of SA in conferring drought tolerance to plants to maintain sustainable yield possess future research interests.
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Affiliation(s)
- Marisha Sharma
- Plant Ecology and Environmental Sciences Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India; Department of Bioscience and Biotechnology, Banasthali University, P.O. Banasthali Vidyapith, 304022, Rajasthan, India
| | - Sunil K Gupta
- Plant Ecology and Environmental Sciences Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India
| | - Baisakhi Majumder
- Plant Ecology and Environmental Sciences Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India
| | - Vivek K Maurya
- Plant Ecology and Environmental Sciences Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India
| | - Farah Deeba
- Plant Ecology and Environmental Sciences Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India; Biotechnology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India
| | - Afroz Alam
- Department of Bioscience and Biotechnology, Banasthali University, P.O. Banasthali Vidyapith, 304022, Rajasthan, India
| | - Vivek Pandey
- Plant Ecology and Environmental Sciences Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India.
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3
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Cabello-Díaz JM, Gálvez-Valdivieso G, Caballo C, Lambert R, Quiles FA, Pineda M, Piedras P. Identification and characterization of a gene encoding for a nucleotidase from Phaseolus vulgaris. JOURNAL OF PLANT PHYSIOLOGY 2015; 185:44-51. [PMID: 26276404 DOI: 10.1016/j.jplph.2015.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 07/07/2015] [Accepted: 07/07/2015] [Indexed: 06/04/2023]
Abstract
Nucleotidases are phosphatases that catalyze the removal of phosphate from nucleotides, compounds with an important role in plant metabolism. A phosphatase enzyme, with high affinity for nucleotides monophosphate previously identified and purified in embryonic axes from French bean, has been analyzed by MALDI TOF/TOF and two internal peptides have been obtained. The information of these peptide sequences has been used to search in the genome database and only a candidate gene that encodes for the phosphatase was identified (PvNTD1). The putative protein contains the conserved domains (motif I-IV) for haloacid dehalogenase-like hydrolases superfamily. The residues involved in the catalytic activity are also conserved. A recombinant protein overexpressed in Escherichia coli has shown molybdate resistant phosphatase activity with nucleosides monophosphate as substrate, confirming that the identified gene encodes for the phosphatase with high affinity for nucleotides purified in French bean embryonic axes. The activity of the purified protein was inhibited by adenosine. The expression of PvNTD1 gene was induced at the specific moment of radicle protrusion in embryonic axes. The gene was also highly expressed in young leaves whereas the level of expression in mature tissues was minimal.
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Affiliation(s)
- Juan Miguel Cabello-Díaz
- Departamento de Botánica, Ecología y Fisiología Vegetal, Grupo de Fisiología Molecular y Biotecnología de Plantas, Campus Rabanales, Edif. Severo Ochoa, 1ª Planta, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Gregorio Gálvez-Valdivieso
- Departamento de Botánica, Ecología y Fisiología Vegetal, Grupo de Fisiología Molecular y Biotecnología de Plantas, Campus Rabanales, Edif. Severo Ochoa, 1ª Planta, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Cristina Caballo
- Departamento de Botánica, Ecología y Fisiología Vegetal, Grupo de Fisiología Molecular y Biotecnología de Plantas, Campus Rabanales, Edif. Severo Ochoa, 1ª Planta, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Rocío Lambert
- Departamento de Botánica, Ecología y Fisiología Vegetal, Grupo de Fisiología Molecular y Biotecnología de Plantas, Campus Rabanales, Edif. Severo Ochoa, 1ª Planta, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Francisco Antonio Quiles
- Departamento de Botánica, Ecología y Fisiología Vegetal, Grupo de Fisiología Molecular y Biotecnología de Plantas, Campus Rabanales, Edif. Severo Ochoa, 1ª Planta, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Manuel Pineda
- Departamento de Botánica, Ecología y Fisiología Vegetal, Grupo de Fisiología Molecular y Biotecnología de Plantas, Campus Rabanales, Edif. Severo Ochoa, 1ª Planta, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Pedro Piedras
- Departamento de Botánica, Ecología y Fisiología Vegetal, Grupo de Fisiología Molecular y Biotecnología de Plantas, Campus Rabanales, Edif. Severo Ochoa, 1ª Planta, Universidad de Córdoba, 14071 Córdoba, Spain.
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4
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Vaishnav A, Kumari S, Jain S, Varma A, Choudhary DK. Putative bacterial volatile-mediated growth in soybean (Glycine max L. Merrill) and expression of induced proteins under salt stress. J Appl Microbiol 2015; 119:539-51. [PMID: 26042866 DOI: 10.1111/jam.12866] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 05/23/2015] [Accepted: 05/23/2015] [Indexed: 12/28/2022]
Abstract
AIMS Plant root-associated rhizobacteria elicit plant immunity referred to as induced systemic tolerance (IST) against multiple abiotic stresses. Among multibacterial determinants involved in IST, the induction of IST and promotion of growth by putative bacterial volatile compounds (VOCs) is reported in the present study. METHODS AND RESULTS To characterize plant proteins induced by putative bacterial VOCs, proteomic analysis was performed by MALDI-MS/MS after exposure of soybean seedlings to a new strain of plant growth promoting rhizobacteria (PGPR) Pseudomonas simiae strain AU. Furthermore, expression analysis by Western blotting confirmed that the vegetative storage protein (VSP), gamma-glutamyl hydrolase (GGH) and RuBisCo large chain proteins were significantly up-regulated by the exposure to AU strain and played a major role in IST. VSP has preponderant roles in N accumulation and mobilization, acid phosphatase activity and Na(+) homeostasis to sustain plant growth under stress condition. More interestingly, plant exposure to the bacterial strain significantly reduced Na(+) and enhanced K(+) and P content in root of soybean seedlings under salt stress. In addition, high accumulation of proline and chlorophyll content also provided evidence of protection against osmotic stress during the elicitation of IST by bacterial exposure. CONCLUSIONS The present study reported for the first time that Ps. simiae produces a putative volatile blend that can enhance soybean seedling growth and elicit IST against 100 mmol l(-1) NaCl stress condition. SIGNIFICANCE AND IMPACT OF THE STUDY The identification of such differentially expressed proteins provide new targets for future studies that will allow assessment of their physiological roles and significance in the response of glycophytes to stresses. Further work should uncover more about the chemical side of VOC compounds and a detailed study about their molecular mechanism responsible for plant growth.
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Affiliation(s)
- A Vaishnav
- Amity Institute of Microbial Technology (AIMT), Noida, India
| | - S Kumari
- Amity Institute of Microbial Technology (AIMT), Noida, India
| | - S Jain
- Amity Institute of Microbial Technology (AIMT), Noida, India
| | - A Varma
- Amity Institute of Microbial Technology (AIMT), Noida, India
| | - D K Choudhary
- Amity Institute of Microbial Technology (AIMT), Noida, India
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5
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Turner GW, Grimes HD, Lange BM. Soybean vegetative lipoxygenases are not vacuolar storage proteins. FUNCTIONAL PLANT BIOLOGY : FPB 2011; 38:778-787. [PMID: 32480935 DOI: 10.1071/fp11047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 07/23/2011] [Indexed: 06/11/2023]
Abstract
The paraveinal mesophyll (PVM) of soybean is a distinctive uniseriate layer of branched cells situated between the spongy and palisade chlorenchyma of leaves that contains an abundance of putative vegetative storage proteins, Vspα and Vspβ, in its vacuoles. Soybean vegetative lipoxygenases (five isozymes designated as Vlx(A-E)) have been reported to co-localise with Vsp in PVM vacuoles; however, conflicting results regarding the tissue-level and subcellular localisations of specific Vlx isozymes have been reported. We employed immuno-cytochemistry with affinity-purified, isozyme-specific antibodies to reinvestigate the subcellular locations of soybean Vlx isozymes during a sink limitation experiment. VlxB and VlxC were localised to the cytoplasm and nucleoplasm of PVM cells, whereas VlxD was present in the cytoplasm and nucleoplasm of mesophyll chlorenchyma (MC) cells. Label was not associated with storage vacuoles or any evident protein bodies, so our results cast doubt on the hypothesis that Vlx isozymes function as vegetative storage proteins.
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Affiliation(s)
- Glenn W Turner
- Institute of Biological Chemistry, Washington State University, Pullman, WA 99164-6340, USA
| | - Howard D Grimes
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164-7520, USA
| | - B Markus Lange
- Institute of Biological Chemistry, Washington State University, Pullman, WA 99164-6340, USA
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6
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Veljanovski V, Major IT, Patton JJ, Bol E, Louvet S, Hawkins BJ, Constabel CP. Induction of acid phosphatase transcripts, protein and enzymatic activity by simulated herbivory of hybrid poplar. PHYTOCHEMISTRY 2010; 71:619-26. [PMID: 20129630 DOI: 10.1016/j.phytochem.2010.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 11/19/2009] [Accepted: 01/06/2010] [Indexed: 05/28/2023]
Abstract
Herbivory and wounding upregulate a large suite of defense genes in hybrid poplar leaves. A strongly wound- and herbivore-induced gene with high similarity to Arabidopsis vegetative storage proteins (VSPs) and acid phosphatase (AP) was identified among genes strongly expressed during the poplar herbivore defense response. Phylogenetic analysis showed that the putative poplar acid phosphatase (PtdAP1) gene is part of an eight-member AP gene family in poplar, and is most closely related to a functionally characterized soybean nodule AP. Unlike the other poplar APs, PtdAP1 is expressed in variety of tissues, as observed in an analysis of EST data. Following wounding, the gene shows an expression profile similar to other known poplar defense genes such as protease inhibitors, chitinase, and polyphenol oxidase. Significantly, we show for the first time that subsequent to the wound-induction of PtdAP1 transcripts, AP protein and activity increase in extracts of leaves and other tissues. Although its mechanism of action is as yet unknown, these results suggest in hybrid poplar PtdAP1 is likely a component of the defense response against leaf-eating herbivores.
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Affiliation(s)
- Vasko Veljanovski
- Centre for Forest Biology, Biology Department, University of Victoria, Victoria, BC, Canada
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7
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Shi ZB, Ge HH, Zhao P, Zhang M. Crystallization and preliminary crystallographic analysis of recombinant VSP1 from Arabidopsis thaliana. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:201-3. [PMID: 20124723 PMCID: PMC2815693 DOI: 10.1107/s1744309109053688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Accepted: 12/14/2009] [Indexed: 11/10/2022]
Abstract
VSP1 is a defence protein in Arabidopsis thaliana that may also be involved in control of plant development. The recombinant protein has been overexpressed in Escherichia coli, purified and crystallized using the sitting-drop vapour-diffusion method. The crystal diffracted to 1.9 A resolution and a complete X-ray data set was collected at 100 K using Cu Kalpha radiation from a rotating-anode X-ray source. The crystals belonged to space group C2. As there are no related structures that could be used as a search model for molecular replacement, work is in progress on experimental phasing using heavy-atom derivatives and selenomethionine derivatives.
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Affiliation(s)
- Zhu-Bing Shi
- School of Life Science, Anhui University, Hefei 230039, People’s Republic of China
| | - Hong-Hua Ge
- School of Life Science, Anhui University, Hefei 230039, People’s Republic of China
| | - Ping Zhao
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, People’s Republic of China
| | - Min Zhang
- School of Life Science, Anhui University, Hefei 230039, People’s Republic of China
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8
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Oehrle NW, Sarma AD, Waters JK, Emerich DW. Proteomic analysis of soybean nodule cytosol. PHYTOCHEMISTRY 2008; 69:2426-38. [PMID: 18757068 DOI: 10.1016/j.phytochem.2008.07.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 06/24/2008] [Accepted: 07/18/2008] [Indexed: 05/13/2023]
Abstract
An isolation procedure for soybean (Glycine max L. cv Williams 82) nodule cytosol proteins was developed which greatly improved protein resolution by two-dimensional polyacrylamide gel electrophoresis. The most abundant proteins were selected and analyzed by mass spectrometry. The identified proteins were categorized by function (% of total proteins analyzed): carbon metabolism (28%), nitrogen metabolism (12%), reactive oxygen metabolism (12%) and vesicular trafficking (11%). The first three categories were expected based on the known physiological functions of the symbiotic nitrogen fixation process. The number of proteins involved in vesicular trafficking suggests a very active exchange of macromolecules and membrane components. Among the 69 identified proteins were the enzymes of the three carbon portion of glycolysis, which were further characterized to support their roles in the sucrose synthase pathway to provide malate for the bacteroids. Proteomic analysis provides a functional tool by which to understand and further investigate nodule function.
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Affiliation(s)
- Nathan W Oehrle
- United States Department of Agriculture, Curtis Hall, University of Missouri, Columbia, MO 65211, United States
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9
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Djordjevic MA, Oakes M, Li DX, Hwang CH, Hocart CH, Gresshoff PM. The glycine max xylem sap and apoplast proteome. J Proteome Res 2007; 6:3771-9. [PMID: 17696379 DOI: 10.1021/pr0606833] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular signaling interactions in the plant apoplast are important for defense and developmental responses. We examined the soybean proteome of the apoplastic conduit of root-to-shoot communication, the xylem stream, using gel electrophoresis combined with two types of tandem mass spectrometry. We examined soybeans for the presence of a Bradyrhizobium japonicum-induced, long distance developmental signal that controls autoregulation of nodulation (AON) to determine if xylem proteins (XPs) were involved directly or indirectly in AON. The xylem and apoplast fluids collected in hypocotyl, epicotyl, and stem tissue contained a highly similar set of secreted proteins. The XPs were different from those secreted from imbibing seed implying they play important basic roles in xylem function. The XPs of wild-type and nts1007 plants were indistinguishable irrespective of plant age, inoculation status, or time after inoculation suggesting that none was directly involved in AON. XPs were continuously loaded into the xylem stream, as they were present even 28 h after shoot decapitation. These results were consistent with semiquantitative RT-PCR studies that examined the expression of genes corresponding to the XPs under inoculated or uninoculated conditions. Monitoring the expression of XP genes by RT-PCR showed that four possessed root biased expression. This suggested that the corresponding protein products could be produced in roots and travel long distances to shoots. Of these, a species of lipid transfer protein is a candidate for a water-soluble, long-distance signal-carrier due to the presence of hydrophobic clefts that bind known plant signals in vitro. Two soybean XPs identified in this study, lipid transfer protein and Kunitz trypsin inhibitor (KTI), have known roles in plant signaling.
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Affiliation(s)
- Michael A Djordjevic
- Australian Research Council Centre of Excellence for Integrative Legume Research, Genomic Interactions Group, Mass Spectrometry Facility, Research School of Biological Science, Australian National University, Canberra ACT.
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Burroughs AM, Allen KN, Dunaway-Mariano D, Aravind L. Evolutionary genomics of the HAD superfamily: understanding the structural adaptations and catalytic diversity in a superfamily of phosphoesterases and allied enzymes. J Mol Biol 2006; 361:1003-34. [PMID: 16889794 DOI: 10.1016/j.jmb.2006.06.049] [Citation(s) in RCA: 321] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 06/16/2006] [Accepted: 06/20/2006] [Indexed: 11/21/2022]
Abstract
The HAD (haloacid dehalogenase) superfamily includes phosphoesterases, ATPases, phosphonatases, dehalogenases, and sugar phosphomutases acting on a remarkably diverse set of substrates. The availability of numerous crystal structures of representatives belonging to diverse branches of the HAD superfamily provides us with a unique opportunity to reconstruct their evolutionary history and uncover the principal determinants that led to their diversification of structure and function. To this end we present a comprehensive analysis of the HAD superfamily that identifies their unique structural features and provides a detailed classification of the entire superfamily. We show that at the highest level the HAD superfamily is unified with several other superfamilies, namely the DHH, receiver (CheY-like), von Willebrand A, TOPRIM, classical histone deacetylases and PIN/FLAP nuclease domains, all of which contain a specific form of the Rossmannoid fold. These Rossmannoid folds are distinguished from others by the presence of equivalently placed acidic catalytic residues, including one at the end of the first core beta-strand of the central sheet. The HAD domain is distinguished from these related Rossmannoid folds by two key structural signatures, a "squiggle" (a single helical turn) and a "flap" (a beta hairpin motif) located immediately downstream of the first beta-strand of their core Rossmanoid fold. The squiggle and the flap motifs are predicted to provide the necessary mobility to these enzymes for them to alternate between the "open" and "closed" conformations. In addition, most members of the HAD superfamily contains inserts, termed caps, occurring at either of two positions in the core Rossmannoid fold. We show that the cap modules have been independently inserted into these two stereotypic positions on multiple occasions in evolution and display extensive evolutionary diversification independent of the core catalytic domain. The first group of caps, the C1 caps, is directly inserted into the flap motif and regulates access of reactants to the active site. The second group, the C2 caps, forms a roof over the active site, and access to their internal cavities might be in part regulated by the movement of the flap. The diversification of the cap module was a major factor in the exploration of a vast substrate space in the course of the evolution of this superfamily. We show that the HAD superfamily contains 33 major families distributed across the three superkingdoms of life. Analysis of the phyletic patterns suggests that at least five distinct HAD proteins are traceable to the last universal common ancestor (LUCA) of all extant organisms. While these prototypes diverged prior to the emergence of the LUCA, the major diversification in terms of both substrate specificity and reaction types occurred after the radiation of the three superkingdoms of life, primarily in bacteria. Most major diversification events appear to correlate with the acquisition of new metabolic capabilities, especially related to the elaboration of carbohydrate metabolism in the bacteria. The newly identified relationships and functional predictions provided here are likely to aid the future exploration of the numerous poorly understood members of this large superfamily of enzymes.
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Affiliation(s)
- A Maxwell Burroughs
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
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11
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Liu Y, Ahn JE, Datta S, Salzman RA, Moon J, Huyghues-Despointes B, Pittendrigh B, Murdock LL, Koiwa H, Zhu-Salzman K. Arabidopsis vegetative storage protein is an anti-insect acid phosphatase. PLANT PHYSIOLOGY 2005; 139:1545-56. [PMID: 16258019 PMCID: PMC1283788 DOI: 10.1104/pp.105.066837] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Indirect evidence previously suggested that Arabidopsis (Arabidopsis thaliana) vegetative storage protein (VSP) could play a role in defense against herbivorous insects. To test this hypothesis, other AtVSP-like sequences in Arabidopsis were identified through a Basic Local Alignment Search Tool search, and their transcriptional profiles were investigated. In response to methyl jasmonate application or phosphate starvation, AtVSP and AtVSP-like genes exhibited differential expression patterns, suggesting distinct roles played by each member. Arabidopsis VSP2 (AtVSP2), a gene induced by wounding, methyl jasmonate, insect feeding, and phosphate deprivation, was selected for bacterial expression and functional characterization. The recombinant protein exhibited a divalent cation-dependent phosphatase activity in the acid pH range. When incorporated into the diets of three coleopteran and dipteran insects that have acidic gut lumen, recombinant AtVSP2 significantly delayed development of the insects and increased their mortality. To further determine the biochemical basis of the anti-insect activity of the protein, the nucleophilic aspartic acid-119 residue at the conserved DXDXT signature motif was substituted by glutamic acid via site-directed mutagenesis. This single-amino acid alteration did not compromise the protein's secondary or tertiary structure, but resulted in complete loss of its acid phosphatase activity as well as its anti-insect activity. Collectively, we conclude that AtVSP2 is an anti-insect protein and that its defense function is correlated with its acid phosphatase activity.
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Affiliation(s)
- Yilin Liu
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA
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