ABSTRACT
Phosphorus is one of the lowest elements absorbed and utilized by plants in the soil. SPX domain-containing genes family play an important role in plant response to phosphate deficiency signaling pathway, and related to seed development, disease resistance, absorption and transport of other nutrients. However, there are no reports on the mechanism of SPX domain-containing genes in response to phosphorus deficiency in eggplant. In this study, the whole genome identification and functional analysis of SPX domain-containing genes family in eggplant were carried out. Sixteen eggplant SPX domain-containing genes were identified and divided into four categories. Subcellular localization showed that these proteins were located in different cell compartments, including nucleus and membrane system. The expression patterns of these genes in different tissues as well as under phosphate deficiency with auxin were explored. The results showed that SmSPX1, SmSPX5 and SmSPX12 were highest expressed in roots. SmSPX1, SmSPX4, SmSPX5 and SmSPX14 were significantly induced by phosphate deficiency and may be the key candidate genes in response to phosphate starvation in eggplant. Among them, SmSPX1 and SmSPX5 can be induced by auxin under phosphate deficiency. In conclusion, our study preliminary identified the SPX domain genes in eggplant, and the relationship between SPX domain-containing genes and auxin was first analyzed in response to phosphate deficiency, which will provide theoretical basis for improving the absorption of phosphorus in eggplants through molecular breeding technology.
Subject(s)
Gene Expression Regulation, Plant , Plant Proteins , Solanum melongena , Solanum melongena/genetics , Solanum melongena/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Indoleacetic Acids/metabolism , Genome, Plant/genetics , Multigene Family , Phosphorus/metabolism , Phosphorus/deficiency , Genes, Plant , Phosphates/metabolism , Phosphates/deficiencyABSTRACT
The molecular basis for bulk autophagy activation due to a deficiency in essential nutrients such as carbohydrates, amino acids, and nitrogen is well understood. Given autophagy functions to reduce surplus to compensate for scarcity, it theoretically possesses the capability to selectively degrade specific substrates to meet distinct metabolic demands. However, direct evidence is still lacking that substantiates the idea that autophagy selectively targets specific substrates (known as selective autophagy) to address particular nutritional needs. Recently, Gross et al. found that during phosphate starvation (P-S), rather than nitrogen starvation (N-S), yeasts selectively eliminate peroxisomes by dynamically altering the composition of the Atg1/ULK kinase complex (AKC) to adapt to P-S. This study elucidates how the metabolite sensor Pho81 flexibly interacts with AKC and guides selective autophagic clearance of peroxisomes during P-S, providing novel insights into the metabolic contribution of autophagy to special nutritional needs.
Subject(s)
Autophagy , Phosphates , Saccharomyces cerevisiae Proteins , Phosphates/metabolism , Phosphates/deficiency , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Peroxisomes/metabolism , Saccharomyces cerevisiae/metabolism , Autophagy-Related Protein-1 Homolog/metabolism , Autophagy-Related Protein-1 Homolog/genetics , Autophagy-Related Proteins/metabolism , Autophagy-Related Proteins/genetics , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Protein KinasesABSTRACT
Phosphorus (P) is a crucial macronutrient required for normal plant growth. Its effective uptake from the soil is a trait of agronomic importance. Natural variation in maize (339 accessions) root traits, namely root length and number of primary, seminal, and crown roots, root and shoot phosphate (Pi) contents, and root-to-shoot Pi translocation (root: shoot Pi) under normal (control, 40 ppm) and low phosphate (LP, 1 ppm) conditions, were used for genome-wide association studies (GWAS). The Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) model of GWAS provided 23 single nucleotide polymorphisms (SNPs) and 12 relevant candidate genes putatively linked with root Pi, root: shoot Pi, and crown root number (CRN) under LP. The DNA-protein interaction analysis of Zm00001d002842, Zm00001d002837, Zm00001d002843 for root Pi, and Zm00001d044312, Zm00001d045550, Zm00001d025915, Zm00001d044313, Zm00001d051842 for root: shoot Pi, and Zm00001d031561, Zm00001d001803, and Zm00001d001804 for CRN showed the presence of potential binding sites of key transcription factors like MYB62, bZIP11, ARF4, ARF7, ARF10 and ARF16 known for induction/suppression of phosphate starvation response (PHR). The in-silico RNA-seq analysis revealed up or down-regulation of candidate genes along with key transcription factors of PHR, while Uniprot analysis provided genetic relatedness. Candidate genes that may play a role in P uptake and root-to-shoot Pi translocation under LP are proposed using common PHR signaling components like MYB62, ARF4, ARF7, ARF10, ARF16, and bZIP11 to induce changes in root growth in maize. Candidate genes may be used to improve low P tolerance in maize using the CRISPR strategy.
Subject(s)
Genome-Wide Association Study , Phosphates , Plant Roots , Polymorphism, Single Nucleotide , Zea mays , Zea mays/genetics , Zea mays/growth & development , Zea mays/metabolism , Plant Roots/genetics , Plant Roots/growth & development , Plant Roots/metabolism , Polymorphism, Single Nucleotide/genetics , Phosphates/metabolism , Phosphates/deficiency , Gene Expression Regulation, Plant , Plant Proteins/genetics , Plant Proteins/metabolism , Linkage Disequilibrium/geneticsABSTRACT
MAIN CONCLUSION: Silicon application mitigates phosphate deficiency in barley through an interplay with auxin and nitric oxide, enhancing growth, photosynthesis, and redox balance, highlighting the potential of silicon as a fertilizer for overcoming nutritional stresses. Silicon (Si) is reported to attenuate nutritional stresses in plants, but studies on the effect of Si application to plants grown under phosphate (Pi) deficiency are still very scarce, especially in barley. Therefore, the present work was undertaken to investigate the potential role of Si in mitigating the adverse impacts of Pi deficiency in barley Hordeum vulgare L. (var. BH902). Further, the involvement of two key regulatory signaling molecules--auxin and nitric oxide (NO)--in Si-induced tolerance against Pi deficiency in barley was tested. Morphological attributes, photosynthetic parameters, oxidative stress markers (O2·-, H2O2, and MDA), antioxidant system (enzymatic--APX, CAT, SOD, GR, DHAR, MDHAR as well as non-enzymatic--AsA and GSH), NO content, and proline metabolism were the key traits that were assessed under different treatments. The P deficiency distinctly declined growth of barley seedlings, which was due to enhancement in oxidative stress leading to inhibition of photosynthesis. These results were also in parallel with an enhancement in antioxidant activity, particularly SOD and CAT, and endogenous proline level and its biosynthetic enzyme (P5CS). The addition of Si exhibited beneficial effects on barley plants grown in Pi-deficient medium as reflected in increased growth, photosynthetic activity, and redox balance through the regulation of antioxidant machinery particularly ascorbate-glutathione cycle. We noticed that auxin and NO were also found to be independently participating in Si-mediated improvement of growth and other parameters in barley roots under Pi deficiency. Data of gene expression analysis for PHOSPHATE TRANSPORTER1 (HvPHT1) indicate that Si helps in increasing Pi uptake as per the need of Pi-deficient barley seedlings, and also auxin and NO both appear to help Si in accomplishing this task probably by inducing lateral root formation. These results are suggestive of possible application of Si as a fertilizer to correct the negative effects of nutritional stresses in plants. Further research at genetic level to understand Si-induced mechanisms for mitigating Pi deficiency can be helpful in the development of new varieties with improved tolerance against Pi deficiency, especially for cultivation in areas with Pi-deficient soils.
Subject(s)
Hordeum , Indoleacetic Acids , Nitric Oxide , Oxidative Stress , Phosphates , Photosynthesis , Plant Roots , Silicon , Hordeum/metabolism , Hordeum/genetics , Hordeum/drug effects , Hordeum/growth & development , Hordeum/physiology , Silicon/pharmacology , Silicon/metabolism , Indoleacetic Acids/metabolism , Phosphates/deficiency , Phosphates/metabolism , Nitric Oxide/metabolism , Plant Roots/metabolism , Plant Roots/growth & development , Plant Roots/drug effects , Plant Roots/genetics , Photosynthesis/drug effects , Antioxidants/metabolism , Seedlings/growth & development , Seedlings/metabolism , Seedlings/genetics , Seedlings/drug effects , Seedlings/physiologyABSTRACT
Phosphorus (P) is an essential macronutrient for plant life and growth. P is primarily acquired in the form of inorganic phosphate (Pi) from soil. To cope with Pi deficiency, plants have evolved an elaborate system to improve Pi acquisition and utilization through an array of developmental and physiological changes, termed Pi starvation response (PSR). Plants also assemble and manage mutualistic microbes to enhance Pi uptake, through integrating PSR and immunity signaling. A trade-off between plant growth and defense favors the notion that plants lower a cellular state of immunity to accommodate host-beneficial microbes for nutrition and growth at the cost of infection risk. However, the existing data indicate that plants selectively activate defense responses against pathogens, but do not or less against non-pathogens, even under nutrient deficiency. In this review, we highlight recent advances in the principles and mechanisms with which plants balance immunity and growth-related processes to optimize their adaptation to Pi deficiency.
Subject(s)
Phosphates , Plant Immunity , Phosphates/deficiency , Phosphates/metabolism , Plants/immunology , Plants/microbiology , Plants/metabolism , Signal TransductionABSTRACT
Plants have evolved finely regulated defense systems to counter biotic and abiotic threats. In the natural environment, plants are typically challenged by simultaneous stresses and, amid such conditions, crosstalk between the activated signaling pathways becomes evident, ultimately altering the outcome of the defense response. As an example of combined biotic and abiotic stresses, inorganic phosphate (Pi) deficiency, common in natural and agricultural environments, can occur along with attack by the fungus Botrytis cinerea, a devastating necrotrophic generalist pathogen responsible for massive crop losses. We report that Pi deficiency in Arabidopsis thaliana increases its susceptibility to infection by B. cinerea by influencing the early stages of pathogen infection, namely spore adhesion and germination on the leaf surface. Remarkably, Pi-deficient plants are more susceptible to B. cinerea despite displaying the appropriate activation of the jasmonic acid and ethylene signaling pathways, as well as producing secondary defense metabolites and reactive oxygen species. Conversely, the callose deposition in response to B. cinerea infection is compromised under Pi-deficient conditions. The levels of abscisic acid (ABA) are increased in Pi-deficient plants, and the heightened susceptibility to B. cinerea observed under Pi deficiency can be reverted by blocking ABA biosynthesis. Furthermore, high level of leaf ABA induced by overexpression of NCED6 in Pi-sufficient plants also resulted in greater susceptibility to B. cinerea infection associated with increased spore adhesion and germination, and reduced callose deposition. Our findings reveal a link between the enhanced accumulation of ABA induced by Pi deficiency and an increased sensitivity to B. cinerea infection.
Subject(s)
Abscisic Acid , Arabidopsis , Botrytis , Phosphates , Plant Diseases , Signal Transduction , Botrytis/physiology , Abscisic Acid/metabolism , Arabidopsis/microbiology , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis/immunology , Plant Diseases/microbiology , Plant Diseases/immunology , Phosphates/metabolism , Phosphates/deficiency , Plant Leaves/microbiology , Plant Leaves/metabolism , Ethylenes/metabolism , Cyclopentanes/metabolism , Plant Growth Regulators/metabolism , Oxylipins/metabolism , Spores, Fungal/physiology , Gene Expression Regulation, Plant , Reactive Oxygen Species/metabolism , Disease SusceptibilitySubject(s)
Hyperphosphatemia , Renal Insufficiency, Chronic , Zinc , Hyperphosphatemia/metabolism , Hyperphosphatemia/etiology , Humans , Zinc/deficiency , Zinc/metabolism , Renal Insufficiency, Chronic/metabolism , Renal Insufficiency, Chronic/physiopathology , Animals , Nutritional Status , Phosphates/metabolism , Phosphates/blood , Phosphates/deficiencyABSTRACT
Inorganic phosphorus (Pi) deficiency significantly impacts plant growth, development, and photosynthetic efficiency. This study evaluated 206 rice accessions from a MiniCore population under both Pi-sufficient (Pi+) and Pi-starvation (Pi-) conditions in the field to assess photosynthetic phosphorus use efficiency (PPUE), defined as the ratio of AsatPi- to AsatPi+. A genome-wide association study and differential gene expression analyses identified an acid phosphatase gene (ACP2) that responds strongly to phosphate availability. Overexpression and knockout of ACP2 led to a 67% increase and 32% decrease in PPUE, respectively, compared with wild type. Introduction of an elite allele A, by substituting the v5 SNP G with A, resulted in an 18% increase in PPUE in gene-edited ACP2 rice lines. The phosphate-responsive gene PHR2 was found to transcriptionally activate ACP2 in parallel with PHR2 overexpression, resulting in an 11% increase in PPUE. Biochemical assays indicated that ACP2 primarily catalyzes the hydrolysis of phosphoethanolamine and phospho-L-serine. In addition, serine levels increased significantly in the ACP2v8G-overexpression line, along with a concomitant decrease in the expression of all nine genes involved in the photorespiratory pathway. Application of serine enhanced PPUE and reduced photorespiration rates in ACP2 mutants under Pi-starvation conditions. We deduce that ACP2 plays a crucial role in promoting photosynthesis adaptation to Pi starvation by regulating serine metabolism in rice.
Subject(s)
Genome-Wide Association Study , Oryza , Phosphates , Photosynthesis , Serine , Oryza/genetics , Oryza/metabolism , Photosynthesis/genetics , Phosphates/metabolism , Phosphates/deficiency , Serine/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant , Acid Phosphatase/genetics , Acid Phosphatase/metabolismABSTRACT
Starvation of Schizosaccharomyces pombe for inorganic phosphate elicits adaptive transcriptome changes in which mRNAs driving ribosome biogenesis, tRNA biogenesis, and translation are globally downregulated, while those for autophagy and phosphate mobilization are upregulated. Here, we interrogated three components of the starvation response: upregulated autophagy; the role of transcription factor Pho7 (an activator of the PHO regulon); and upregulated expression of ecl3, one of three paralogous genes (ecl1, ecl2, and ecl3) collectively implicated in cell survival during other nutrient stresses. Ablation of autophagy factor Atg1 resulted in early demise of phosphate-starved fission yeast, as did ablation of Pho7. Transcriptome profiling of phosphate-starved pho7Δ cells highlighted Pho7 as an activator of genes involved in phosphate acquisition and mobilization, not limited to the original three-gene PHO regulon, and additional starvation-induced genes (including ecl3) not connected to phosphate dynamics. Pho7-dependent gene induction during phosphate starvation tracked with the presence of Pho7 DNA-binding elements in the gene promoter regions. Fewer ribosome protein genes were downregulated in phosphate-starved pho7Δ cells versus WT, which might contribute to their shortened lifespan. An ecl3Δ mutant elicited no gene expression changes in phosphate-replete cells and had no impact on survival during phosphate starvation. By contrast, pan-ecl deletion (ecl123Δ) curtailed lifespan during chronic phosphate starvation. Phosphate-starved ecl123Δ cells experienced a more widespread downregulation of mRNAs encoding aminoacyl tRNA synthetases vis-à-vis WT or pho7Δ cells. Collectively, these results enhance our understanding of fission yeast phosphate homeostasis and survival during nutrient deprivation.
Subject(s)
DNA-Binding Proteins , Longevity , Phosphates , Schizosaccharomyces pombe Proteins , Schizosaccharomyces , Transcription Factors , Gene Expression Regulation, Fungal , Longevity/genetics , Phosphates/deficiency , RNA, Transfer/metabolism , Schizosaccharomyces/genetics , Schizosaccharomyces/metabolism , Schizosaccharomyces pombe Proteins/genetics , Schizosaccharomyces pombe Proteins/metabolism , Transcriptome , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
Phosphorus is indispensable in agricultural production. An increasing food supply requires more efficient use of phosphate due to limited phosphate resources. However, how crops regulate phosphate efficiency remains largely unknown. Here, we identified a major quantitative trait locus, qPE19, that controls 7 low-phosphate (LP)-related traits in soybean (Glycine max) through linkage mapping and genome-wide association studies. We identified the gene responsible for qPE19 as GLYCEROPHOSPHORYL DIESTER PHOSPHODIESTERASE2 (GmGDPD2), and haplotype 5 represents the optimal allele favoring LP tolerance. Overexpression of GmGDPD2 significantly affects hormone signaling and improves root architecture, phosphate efficiency and yield-related traits; conversely, CRISPR/Cas9-edited plants show decreases in these traits. GmMyb73 negatively regulates GmGDPD2 by directly binding to its promoter; thus, GmMyb73 negatively regulates LP tolerance. GmGDPD2 physically interacts with GA 2-oxidase 1 (GmGA2ox1) in the plasma membrane, and overexpressing GmGA2ox1 enhances LP-associated traits, similar to GmGDPD2 overexpression. Analysis of double mutants for GmGDPD2 and GmGA2ox1 demonstrated that GmGDPD2 regulates LP tolerance likely by influencing auxin and gibberellin dose-associated cell division in the root. These results reveal a regulatory module that plays a major role in regulating LP tolerance in soybeans and is expected to be utilized to develop phosphate-efficient varieties to enhance soybean production, particularly in phosphate-deficient soils.
Subject(s)
Gene Expression Regulation, Plant , Glycine max , Phosphates , Plant Proteins , Glycine max/genetics , Glycine max/metabolism , Phosphates/metabolism , Phosphates/deficiency , Plant Proteins/genetics , Plant Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Quantitative Trait Loci/genetics , Plants, Genetically Modified , Genome-Wide Association StudySubject(s)
Glycine max , Phosphates , Plant Proteins , Glycine max/genetics , Glycine max/metabolism , Phosphates/deficiency , Phosphates/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
Strigolactones (SLs) are fundamental to the ability of plants to cope with phosphate deficiency. A recent study by Yuan et al. indicates that the genetic module PHR2/NSP1/NSP2 is crucial in activating SL biosynthesis and signaling under inorganic phosphate (Pi) deficiency. Furthermore, this genetic module is essential for improving Pi and nitrogen homeostasis in rice.
Subject(s)
Crops, Agricultural , Lactones , Oryza , Lactones/metabolism , Crops, Agricultural/genetics , Crops, Agricultural/metabolism , Oryza/genetics , Oryza/metabolism , Plant Proteins/metabolism , Plant Proteins/genetics , Phosphates/metabolism , Phosphates/deficiency , Plant Growth Regulators/metabolism , Gene Expression Regulation, PlantABSTRACT
We retrieved a series of measurements made 35 years ago of the concentration of inorganic phosphate (P) in the serum from 56 cases of severe protein-energy malnutrition at the Tropical Metabolism Research Unit, Jamaica. There is no record of whether or not the cases were randomly selected. The samples were obtained within 4 days of admission and except in 3 cases there was no follow-up. The average age was 12 months. The children have been classified retrospectively from the notes as marasmus (11 cases), kwashiorkor (22 cases) and marasmic kwashiokor (23 cases). In all 11 children died (fatality rate 20 percent), eight of them from the group with marasmic kwashiorkor. Weight-for-age, length-for-age and weight-for-length have been calculated as Z-scores. Nearly all serum phosphate concentrations were low (mean 1.41 mmol.1-1, SD 0.444, range 0.50-2.45) compared with the normal value at this age of about 2 mmol.1-1. The serum P was significantly less depressed in the marasmic children (P=0.042), but there was no relation between serum P and any of the anthropometric measurements, nor with outcome (death or survival). There was, however, a significant relationship with the degree of oedema. Death was related to age - the children who died were younger (mean difference 3.8 months; P=0.01; 95 percent confidence interval 0.23-6.43). It took about 3 weeks of feeding a milk-based diet for serum phosphate to reach normal levels. There have been few previous measurements of serum P in malnutrition. We agree with previous authors that the low serum values are evidence of phosphate depletion and suggest that phosphate might be added to the electrolyte solutions used in the early stages of recovery. However, reports of adverse effects indicate that this should be done with great care (AU)