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1.
Sci Rep ; 14(1): 8347, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594297

RESUMO

Phosphatized fish fossils occur in various locations worldwide. Although these fossils have been intensively studied over the past decades they remain a matter of ongoing research. The mechanism of the permineralization reaction itself remains still debated in the community. The mineralization in apatite of a whole fish requires a substantial amount of phosphate which is scarce in seawater, so the origin of the excess is unknown. Previous research has shown that alkaline phosphatase, a ubiquitous enzyme, can increase the phosphate content in vitro in a medium to the degree of saturation concerning apatite. We applied this principle to an experimental setup where fish scales were exposed to commercial bovine alkaline phosphatase. We analyzed the samples with SEM and TEM and found that apatite crystals had formed on the remaining soft tissue. A comparison of these newly formed apatite crystals with fish fossils from the Solnhofen and Santana fossil deposits showed striking similarities. Both are made up of almost identically sized and shaped nano-apatites. This suggests a common formation process: the spontaneous precipitation from an oversaturated solution. The excess activity of alkaline phosphatase could explain that effect. Therefore, our findings could provide insight into the formation of well-preserved fossils.


Assuntos
Fosfatase Alcalina , Apatitas , Animais , Bovinos , Apatitas/química , Fosfatos/metabolismo , Fósseis
2.
Water Res ; 254: 121411, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38457945

RESUMO

To combat the global loss of wetlands and their essential functions, the restoration and creation of wetlands is imperative. However, wetland development is challenging when soils have been in prolonged agricultural use, often resulting in a substantial nutrient legacy, especially of phosphorous (P). Inundating these soils typically leads to P mobilization, resulting in poor water quality and low biodiversity recovery. As a potential novel means to overcome this challenge, we tested whether cultivation of the floating fern Azolla filiculoides could simultaneously extract and recycle P, and provide a commercial product. Azolla has high growth rates due to the nitrogen fixing capacity of its microbiome and is capable of luxury consumption of P. Azolla cultivation may also accelerate soil P mobilization and subsequent extraction by causing surface water anoxia and the release of iron-bound P. To test this approach, we cultivated Azolla on 15 P-rich former agricultural soils in an indoor mesocosm experiment. Soils were inundated and either left unvegetated or inoculated with A. filiculoides during two 8-week cultivation periods. Biomass was harvested at different intervals (weekly/monthly/bimonthly) to investigate the effect of harvesting frequency on oxygen (O2) and nutrient dynamics. We found that Azolla attained high growth rates only on soils with high mobilization of labile P, as plant cover did not reduce surface water O2 concentrations in the first phase after inundation. This concurred with low porewater iron to P ratios (<10) and high porewater P concentrations. A. filiculoides cultivation substantially reduced surface water nutrient concentrations and extracted P at rates up to 122 kg ha-1 yr-1. We conclude that rapid P extraction by A. filiculoides cultivation is possible on soils rich in labile P, offering new perspectives for wetland rehabilitation. Additional field trials are recommended to investigate long-term feasibility, seasonal variations, and the influence of potential grazers and pathogens.


Assuntos
Gleiquênias , Fosfatos , Fosfatos/metabolismo , Solo , Gleiquênias/metabolismo , Plantas , Ferro/metabolismo
3.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38486365

RESUMO

AIMS: This study aimed to isolate plant growth and drought tolerance-promoting bacteria from the nutrient-poor rhizosphere soil of Thar desert plants and unravel their molecular mechanisms of plant growth promotion. METHODS AND RESULTS: Among our rhizobacterial isolates, Enterobacter cloacae C1P-IITJ, Kalamiella piersonii J4-IITJ, and Peribacillus frigoritolerans T7-IITJ, significantly enhanced root and shoot growth (4-5-fold) in Arabidopsis thaliana under PEG-induced drought stress. Whole genome sequencing and biochemical analyses of the non-pathogenic bacterium T7-IITJ revealed its plant growth-promoting traits, viz., solubilization of phosphate (40-73 µg/ml), iron (24 ± 0.58 mm halo on chrome azurol S media), and nitrate (1.58 ± 0.01 µg/ml nitrite), along with production of exopolysaccharides (125 ± 20 µg/ml) and auxin-like compounds (42.6 ± 0.05 µg/ml). Transcriptome analysis of A. thaliana inoculated with T7-IITJ and exposure to drought revealed the induction of 445 plant genes (log2fold-change > 1, FDR < 0.05) for photosynthesis, auxin and jasmonate signalling, nutrient uptake, redox homeostasis, and secondary metabolite biosynthesis pathways related to beneficial bacteria-plant interaction, but repression of 503 genes (log2fold-change < -1) including many stress-responsive genes. T7-IITJ enhanced proline 2.5-fold, chlorophyll 2.5-2.8-fold, iron 2-fold, phosphate 1.6-fold, and nitrogen 4-fold, and reduced reactive oxygen species 2-4.7-fold in plant tissues under drought. T7-IITJ also improved the germination and seedling growth of Tephrosia purpurea, Triticum aestivum, and Setaria italica under drought and inhibited the growth of two plant pathogenic fungi, Fusarium oxysporum, and Rhizoctonia solani. CONCLUSIONS: P. frigoritolerans T7-IITJ is a potent biofertilizer that regulates plant genes to promote growth and drought tolerance.


Assuntos
Arabidopsis , Bacillus , Arabidopsis/genética , Arabidopsis/metabolismo , Genes de Plantas , Ácidos Indolacéticos/metabolismo , Bactérias , Fosfatos/metabolismo , Ferro/metabolismo , Raízes de Plantas/microbiologia , Secas
4.
Biosci Rep ; 44(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38465463

RESUMO

Parathyroid hormone (PTH) and fibroblast growth factor-23 (FGF23) control extracellular phosphate levels by regulating renal NPT2A-mediated phosphate transport by a process requiring the PDZ scaffold protein NHERF1. NHERF1 possesses two PDZ domains, PDZ1 and PDZ2, with identical core-binding GYGF motifs explicitly recognizing distinct binding partners that play different and specific roles in hormone-regulated phosphate transport. The interaction of PDZ1 and the carboxy-terminal PDZ-binding motif of NPT2A (C-TRL) is required for basal phosphate transport. PDZ2 is a regulatory domain that scaffolds multiple biological targets, including kinases and phosphatases involved in FGF23 and PTH signaling. FGF23 and PTH trigger disassembly of the NHERF1-NPT2A complex through reversible hormone-stimulated phosphorylation with ensuing NPT2A sequestration, down-regulation, and cessation of phosphate absorption. In the absence of NHERF1-NPT2A interaction, inhibition of FGF23 or PTH signaling results in disordered phosphate homeostasis and phosphate wasting. Additional studies are crucial to elucidate how NHERF1 spatiotemporally coordinates cellular partners to regulate extracellular phosphate levels.


Assuntos
Hormônio Paratireóideo , Trocadores de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/metabolismo , Transporte de Íons , Hormônio Paratireóideo/metabolismo , Transporte Biológico , Fosfatos/metabolismo , Fosfoproteínas/metabolismo
5.
Methods Mol Biol ; 2754: 551-560, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512689

RESUMO

The study of Tau protein in disease-relevant neuronal cells in culture requires efficient delivery systems for transfection of exogenous Tau and also modulators and interactors of Tau. Transfection of cultivated cells using calcium phosphate precipitation is a simple and cost-effective approach, also for difficult-to-transfect and sensitive cells such as primary neurons. Because of its low cell toxicity and ease of use, the Ca2+-phosphate transfection method is one of the most widely used gene transfer procedures in neuroscience. However, Ca2+-phosphate transfection efficacy in neurons is poor, often in the range of 1-5%, limiting its use in functional investigations. Here, we outline our improved Ca2+-phosphate transfection methodology for human iPSC-derived neurons that yields a reasonable efficiency (20-30% for bright volume markers) without apparent effects on cell health. We have used it to introduce wild-type and mutant human Tau with and without co-transfection of a volume marker (used here: tdTomato). In sum, our procedure can deliver neuronal genes (e.g., MAPT) using typical eukaryotic expression vectors (e.g., using CMV promoter) and is optimized for transfection of human iPSC-derived neurons.


Assuntos
Células-Tronco Pluripotentes Induzidas , Proteínas tau , Humanos , Proteínas tau/genética , Proteínas tau/metabolismo , Cálcio/metabolismo , Transfecção , Fosfatos de Cálcio , Fosfatos/metabolismo , Neurônios/metabolismo
6.
Nat Commun ; 15(1): 2269, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480682

RESUMO

Primary familial brain calcification (PFBC) is characterized by calcium deposition in the brain, causing progressive movement disorders, psychiatric symptoms, and cognitive decline. PFBC is a heterogeneous disorder currently linked to variants in six different genes, but most patients remain genetically undiagnosed. Here, we identify biallelic NAA60 variants in ten individuals from seven families with autosomal recessive PFBC. The NAA60 variants lead to loss-of-function with lack of protein N-terminal (Nt)-acetylation activity. We show that the phosphate importer SLC20A2 is a substrate of NAA60 in vitro. In cells, loss of NAA60 caused reduced surface levels of SLC20A2 and a reduction in extracellular phosphate uptake. This study establishes NAA60 as a causal gene for PFBC, provides a possible biochemical explanation of its disease-causing mechanisms and underscores NAA60-mediated Nt-acetylation of transmembrane proteins as a fundamental process for healthy neurobiological functioning.


Assuntos
Encefalopatias , Humanos , Acetilação , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encefalopatias/genética , Padrões de Herança , Mutação , Fosfatos/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo
7.
Sci Rep ; 14(1): 5806, 2024 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461203

RESUMO

Due to the non-degradable and persistent nature of metal ions in the environment, they are released into water bodies, where they accumulate in fish. In order to assess pollution in fish, the enzyme, glucose 6-phosphate dehydrogenase (G6PD), has been employed as a biomarker due to sensitivity to various ions. This study investigates the kinetic properties of the G6PD enzyme in yellow catfish (Pelteobagrus fulvidraco), and analyzes the effects of these metal ions on the G6PD enzyme activity in the ovarian cell line (CCO) of channel catfish (Ictalurus punctatus). IC50 values and inhibition types of G6PD were determined in the metal ions Cu2+, Al3+, Zn2+, and Cd2+. While, the inhibition types of Cu2+ and Al3+ were the competitive inhibition, Zn2+ and Cd2+ were the linear mixed noncompetitive and linear mixed competitive, respectively. In vitro experiments revealed an inverse correlation between G6PD activity and metal ion concentration, mRNA levels and enzyme activity of G6PD increased at the lower metal ion concentration and decreased at the higher concentration. Our findings suggest that metal ions pose a significant threat to G6PD activity even at low concentrations, potentially playing a crucial role in the toxicity mechanism of metal ion pollution. This information contributes to the development of a biomonitoring tool for assessing metal ion contamination in aquatic species.


Assuntos
Cádmio , Peixes-Gato , Animais , Cádmio/toxicidade , Cádmio/metabolismo , Metais/farmacologia , Metais/metabolismo , Glucosefosfato Desidrogenase/genética , Peixes-Gato/fisiologia , Íons/metabolismo , Glucose/metabolismo , Fosfatos/metabolismo
8.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38431846

RESUMO

Viruses are a major control on populations of microbes. Often, their virulence is examined in controlled laboratory conditions. Yet, in nature, environmental conditions lead to changes in host physiology and fitness that may impart both costs and benefits on viral success. Phosphorus (P) is a major abiotic control on the marine cyanobacterium Synechococcus. Some viruses infecting Synechococcus have acquired, from their host, a gene encoding a P substrate binding protein (PstS), thought to improve virus replication under phosphate starvation. Yet, pstS is uncommon among cyanobacterial viruses. Thus, we asked how infections with viruses lacking PstS are affected by P scarcity. We show that the production of infectious virus particles of such viruses is reduced in low P conditions. However, this reduction in progeny is not caused by impaired phage genome replication, thought to be a major sink for cellular phosphate. Instead, transcriptomic analysis showed that under low P conditions, a PstS-lacking cyanophage increased the expression of a specific gene set that included mazG, hli2, and gp43 encoding a pyrophosphatase, a high-light inducible protein and DNA polymerase, respectively. Moreover, several of the upregulated genes were controlled by the host's phoBR two-component system. We hypothesize that recycling and polymerization of nucleotides liberates free phosphate and thus allows viral morphogenesis, albeit at lower rates than when phosphate is replete or when phages encode pstS. Altogether, our data show how phage genomes, lacking obvious P-stress-related genes, have evolved to exploit their host's environmental sensing mechanisms to coordinate their own gene expression in response to resource limitation.


Assuntos
Bacteriófagos , Synechococcus , Synechococcus/metabolismo , Bacteriófagos/genética , Bacteriófagos/metabolismo , Fosfatos/metabolismo , Fósforo/metabolismo , Proteínas de Transporte
9.
PLoS Genet ; 20(3): e1011059, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38466775

RESUMO

RpoS is an alternative sigma factor needed for the induction of the general stress response in many gammaproteobacteria. Tight regulation of RpoS levels and activity is required for bacterial growth and survival under stress. In Escherichia coli, various stresses lead to higher levels of RpoS due to increased translation and decreased degradation. During non-stress conditions, RpoS is unstable, because the adaptor protein RssB delivers RpoS to the ClpXP protease. RpoS degradation is prevented during stress by the sequestration of RssB by anti-adaptors, each of which is induced in response to specific stresses. Here, we examined how the stabilization of RpoS is reversed during recovery of the cell from stress. We found that RpoS degradation quickly resumes after recovery from phosphate starvation, carbon starvation, and when transitioning from stationary phase back to exponential phase. This process is in part mediated by the anti-adaptor IraP, known to promote RpoS stabilization during phosphate starvation via the sequestration of adaptor RssB. The rapid recovery from phosphate starvation is dependent upon a feedback loop in which RpoS transcription of rssB, encoding the adaptor protein, plays a critical role. Crl, an activator of RpoS that specifically binds to and stabilizes the complex between the RNA polymerase and RpoS, is also required for the feedback loop to function efficiently, highlighting a critical role for Crl in restoring RpoS basal levels.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Retroalimentação , Fator sigma/genética , Fator sigma/metabolismo , Fosfatos/metabolismo , Regulação Bacteriana da Expressão Gênica
10.
J Biol Chem ; 300(3): 105696, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301888

RESUMO

Interferon-gamma-inducible large GTPases, hGBPs, possess antipathogenic and antitumor activities in human cells. Like hGBP1, its closest homolog, hGBP3 has two domains; an N-terminal catalytic domain and a C-terminal helical domain, connected by an intermediate region. The biochemical function of this protein and the role of its domains in substrate hydrolysis have not yet been investigated. Here, we report that while hGBP3 can produce both GDP and GMP, GMP is the minor product, 30% (unlike 85% in hGBP1), indicating that hGBP3 is unable to produce enhanced GMP. To understand which domain(s) are responsible for this deficiency, we created hGBP3 truncated variants. Surprisingly, GMP production was similar upon deletion of the helical domain, suggesting that in contrast to hGBP1, the helical domain of hGBP3 cannot stimulate the second phosphate cleavage of GTP. We conducted computational and solution studies to understand the underlying basis. We found that the regulatory residue W79, present in the catalytic domain, forms an H-bond with the backbone carbonyl of K76 (located in the catalytic loop) of the substrate-bound hGBP3. However, after gamma-phosphate cleavage of GTP, the W79-containing region does not undergo a conformational change, failing to redirect the catalytic loop toward the beta-phosphate. This is necessary for efficient GMP formation because hGBP homologs utilize the same catalytic residue for both phosphate cleavages. We suggest that the lack of specific interdomain contacts mediated by the helical domain prevents the catalytic loop movement, resulting in reduced GMP formation. These findings may provide insight into how hGBP3 contributes to immunity.


Assuntos
Domínio Catalítico , Proteínas de Ligação ao GTP , Guanosina Trifosfato , Fosfatos , Humanos , Domínio Catalítico/genética , GTP Fosfo-Hidrolases/metabolismo , Guanosina Trifosfato/metabolismo , Fosfatos/metabolismo , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo
11.
Sci Adv ; 10(9): eadj3864, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416829

RESUMO

Wall teichoic acid (WTA), a covalent adduct of Gram-positive bacterial cell wall peptidoglycan, contributes directly to virulence and antibiotic resistance in pathogenic species. Polymerization of the Staphylococcus aureus WTA ribitol-phosphate chain is catalyzed by TarL, a member of the largely uncharacterized TagF-like family of membrane-associated enzymes. We report the cryo-electron microscopy structure of TarL, showing a tetramer that forms an extensive membrane-binding platform of monotopic helices. TarL is composed of an amino-terminal immunoglobulin-like domain and a carboxyl-terminal glycosyltransferase-B domain for ribitol-phosphate polymerization. The active site of the latter is complexed to donor substrate cytidine diphosphate-ribitol, providing mechanistic insights into the catalyzed phosphotransfer reaction. Furthermore, the active site is surrounded by electropositive residues that serve to retain the lipid-linked acceptor for polymerization. Our data advance general insight into the architecture and membrane association of the still poorly characterized monotopic membrane protein class and present molecular details of ribitol-phosphate polymerization that may aid in the design of new antimicrobials.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Microscopia Crioeletrônica , Staphylococcus aureus Resistente à Meticilina/metabolismo , Virulência , Ribitol/metabolismo , Ácidos Teicoicos/análise , Ácidos Teicoicos/química , Ácidos Teicoicos/metabolismo , Fosfatos/metabolismo , Resistência Microbiana a Medicamentos
12.
Biochem J ; 481(5): 363-385, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38421035

RESUMO

The plant macronutrient phosphorus is a scarce resource and plant-available phosphate is limiting in most soil types. Generally, a gene regulatory module called the phosphate starvation response (PSR) enables efficient phosphate acquisition by roots and translocation to other organs. Plants growing on moderate to nutrient-rich soils need to co-ordinate availability of different nutrients and repress the highly efficient PSR to adjust phosphate acquisition to the availability of other macro- and micronutrients, and in particular nitrogen. PSR repression is mediated by a small family of single SYG1/Pho81/XPR1 (SPX) domain proteins. The SPX domain binds higher order inositol pyrophosphates that signal cellular phosphorus status and modulate SPX protein interaction with PHOSPHATE STARVATION RESPONSE1 (PHR1), the central transcriptional regulator of PSR. Sequestration by SPX repressors restricts PHR1 access to PSR gene promoters. Here we focus on SPX4 that primarily acts in shoots and sequesters many transcription factors other than PHR1 in the cytosol to control processes beyond the classical PSR, such as nitrate, auxin, and jasmonic acid signalling. Unlike SPX1 and SPX2, SPX4 is subject to proteasomal degradation not only by singular E3 ligases, but also by SCF-CRL complexes. Emerging models for these different layers of control and their consequences for plant acclimation to the environment will be discussed.


Assuntos
Fosfatos , Fósforo , Fosfatos/metabolismo , Fósforo/metabolismo , Fatores de Transcrição/metabolismo , Plantas/genética , Plantas/metabolismo , Ubiquitinação , Regulação da Expressão Gênica de Plantas
13.
Int J Mol Sci ; 25(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38338685

RESUMO

High dietary phosphorus intake (P-In) and high acid loads may adversely affect kidney function. In animal models, excessive phosphorus intake causes renal injury, which, in humans, is also inducible by chronic metabolic acidosis. We thus examined whether habitually high P-In and endogenous acid production during childhood and adolescence may be early indicators of incipient renal inflammatory processes later in adulthood. P-In and acid-base status were longitudinally and exclusively determined by biomarker-based assessment in 277 healthy children, utilizing phosphate and net acid excretion (NAE) measurements in 24 h urine samples repeatedly collected between the ages of 3 and 17 years. Standard deviation scores (by sex and age) were calculated for anthropometric data and for the urinary biomarkers available within age range 3-17 years. Multivariable linear regression was used to analyze the relations of phosphate excretion and NAE with the adulthood outcome circulating interleukin-18 (IL-18), a marker of inflammation and kidney dysfunction. After adjusting for growth- and adulthood-related covariates and pro-inflammatory biomarkers to rule out confounding by non-renal inflammatory processes, regression models revealed a significant positive relationship of long-term NAE (p = 0.01), but not of long-term phosphate excretion with adult serum IL-18. Similar significant positive regression results were obtained after replacing NAE with 24 h urinary ammonium excretion as the exposition variable. Our results suggest that even moderate elevations in renal ammonia production, as caused by habitually higher acid loading during growth, may affect the intrarenal pro-inflammatory system in the long-term, known to be boosted by acidosis-induced raised ammoniagenesis.


Assuntos
Acidose , Interleucina-18 , Rim , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Humanos , Acidose/metabolismo , Biomarcadores/metabolismo , Interleucina-18/metabolismo , Rim/metabolismo , Fosfatos/metabolismo
14.
Nat Commun ; 15(1): 1674, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395951

RESUMO

The Escherichia coli TetR-related transcriptional regulator RutR is involved in the coordination of pyrimidine and purine metabolism. Here we report that lysine acetylation modulates RutR function. Applying the genetic code expansion concept, we produced site-specifically lysine-acetylated RutR proteins. The crystal structure of lysine-acetylated RutR reveals how acetylation switches off RutR-DNA-binding. We apply the genetic code expansion concept in E. coli in vivo revealing the consequences of RutR acetylation on the transcriptional level. We propose a model in which RutR acetylation follows different kinetic profiles either reacting non-enzymatically with acetyl-phosphate or enzymatically catalysed by the lysine acetyltransferases PatZ/YfiQ and YiaC. The NAD+-dependent sirtuin deacetylase CobB reverses enzymatic and non-enzymatic acetylation of RutR playing a dual regulatory and detoxifying role. By detecting cellular acetyl-CoA, NAD+ and acetyl-phosphate, bacteria apply lysine acetylation of transcriptional regulators to sense the cellular metabolic state directly adjusting gene expression to changing environmental conditions.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Lisina/metabolismo , Acetilação , NAD/metabolismo , Expressão Gênica , Fosfatos/metabolismo
15.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396761

RESUMO

A variety of changes in mineral metabolism aiming to restore acid-base balance occur in acid loading and metabolic acidosis. Phosphate plays a key role in defense against metabolic acidosis, both as an intracellular and extracellular buffer, as well as in the renal excretion of excess acid in the form of urinary titratable acid. The skeleton acts as an extracellular buffer in states of metabolic acidosis, as the bone matrix demineralizes, leading to bone apatite dissolution and the release of phosphate, calcium, carbonate, and citrate into the circulation. The renal handling of calcium, phosphate and citrate is also affected, with resultant hypercalciuria, hyperphosphaturia and hypocitraturia.


Assuntos
Acidose , Nefropatias , Humanos , Cálcio/metabolismo , Rim/metabolismo , Acidose/metabolismo , Ácido Cítrico , Citratos , Cálcio da Dieta , Fosfatos/metabolismo
16.
Int J Mol Sci ; 25(4)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38396886

RESUMO

Phosphate (Pi) starvation is a critical factor limiting crop growth, development, and productivity. Rice (Oryza sativa) R2R3-MYB transcription factors function in the transcriptional regulation of plant responses to various abiotic stresses and micronutrient deprivation, but little is known about their roles in Pi starvation signaling and Pi homeostasis. Here, we identified the R2R3-MYB transcription factor gene OsMYB58, which shares high sequence similarity with AtMYB58. OsMYB58 expression was induced more strongly by Pi starvation than by other micronutrient deficiencies. Overexpressing OsMYB58 in Arabidopsis thaliana and rice inhibited plant growth and development under Pi-deficient conditions. In addition, the overexpression of OsMYB58 in plants exposed to Pi deficiency strongly affected root development, including seminal root, lateral root, and root hair formation. Overexpressing OsMYB58 strongly decreased the expression of the rice microRNAs OsmiR399a and OsmiR399j. By contrast, overexpressing OsMYB58 strongly increased the expression of rice PHOSPHATE 2 (OsPHO2), whose expression is repressed by miR399 during Pi starvation signaling. OsMYB58 functions as a transcriptional repressor of the expression of its target genes, as determined by a transcriptional activity assay. These results demonstrate that OsMYB58 negatively regulates OsmiR399-dependent Pi starvation signaling by enhancing OsmiR399s expression.


Assuntos
Arabidopsis , Oryza , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Plantas/metabolismo , Fosfatos/metabolismo , Homeostase , Arabidopsis/genética , Arabidopsis/metabolismo , Desenvolvimento Vegetal , Micronutrientes/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Oryza/genética , Oryza/metabolismo
17.
J Biol Chem ; 300(3): 105718, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311173

RESUMO

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.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Transcriptoma , Fosfatos/metabolismo , Longevidade , RNA de Transferência/metabolismo , Regulação Fúngica da Expressão Gênica
18.
Plant Physiol Biochem ; 208: 108389, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377886

RESUMO

Purple acid phosphatases (PAPs) are involved in activating the rhizosphere's organic phosphorus (P) and promoting P recycling during plant development, especially under the long-term P deficiency conditions in acid soil. However, the function of BnaPAPs in response to P deficiency stress in Brassica napus has rarely been explored. In this study, we found that the acid phosphatase activities (APA) of rapeseed shoot and root increased under P deficienct conditions. Genome-wide identification found that 82 PAP genes were unevenly distributed on 19 chromosomes in B. napus, which could be divided into eight subfamilies. The segmental duplication events were the main driving force for expansion during evolution, and the gene structures and conserved motifs of most members within the same subfamily were highly conservative. Moreover, the expression levels of 37 and 23 different expressed genes were induced by low P in leaf and root, respectively. BnaA09.PAP10a and BnaC09.PAP10a were identified as candidate genes via interaction networks. Significantly, both BnaPAP10a overexpression lines significantly increased root-related APA and total phosphate concentration under P deficiency and ATP supply conditions, thereby improving plant growth and root length. In summary, our results provided a valuable foundation for further study of BnaPAP functions.


Assuntos
Brassica napus , Brassica napus/metabolismo , Família Multigênica , Homeostase , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Fosfatos/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/metabolismo
19.
BMC Plant Biol ; 24(1): 125, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38373884

RESUMO

BACKGROUND: Zinc (Zn) and nickel (Ni) are nutrients that are crucial for plant growth; however, when they are present at higher concentrations, they can cause toxicity in plants. The present study aimed to isolate plant growth promoting endophytic bacteria from Viburnum grandiflorum and assess its plant and defense promoting potential alone and in combination with RP in zinc (Zn) and nickel (Ni) toxic soil. The isolated endophytic bacteria were identified using 16s rRNA gene sequencing. For the experiment, twelve different treatments were applied using Zn, Ni, isolated endophytic Bacillus mycoides (Accession # MW979613), and rock phosphate (RP). The Ni, Zn and RP were used at the rate of (100 mg/kg) and (0.2 g/kg) respectively. A pot experiment with three replicates of each treatment was conducted using a complete randomized design (CRD). RESULTS: The results indicated that Ni (T5 = seed + 100 mg/kg Ni and T9 = seed + 100 mg/kg Zn) and Zn concentrations inhibited plant growth, but the intensity of growth inhibition was higher in Ni-contaminated soil. Bacillus mycoides and RP at 100 mg/Kg Zn (T12 = inoculated seed + 100 mg/kg Zn + RP0.2 g/kg.) increased the shoot length, leaf width, protein and sugar content by 57%, 13%, 20% and 34%, respectively, compared to the control. The antioxidant enzymes superoxide dismutases (SOD), peroxidase (POD) were decreased in contaminated soil. Furthermore, Ni and Zn accumulation was inhibited in T11 (seed + 100 mg/kg Zn + RP0.2 g/Kg) and T12 (inoculated seed + 100 mg/kg Zn + RP0.2 g/Kg) by 62 and 63% respectively. The Cu, Ca, and K, contents increased by 128, 219 and 85, Mn, Na, and K by 326, 449, and 84% in (T3 = inoculated seed) and (T4 = inoculated seed + RP 0.2 g/Kg) respectively. CONCLUSIONS: Ni was more toxic to plants than Zn, but endophytic bacteria isolated from Viburnum grandiflorum, helped wheat (Triticum aestivum) plants and reduced the toxic effects of Ni and Zn. The effect of Bacillus mycoides was more prominent in combination with RP which promoted and suppressed heavy-metal toxicity. The reported combination of Bacillus mycoides and RP may be useful for improving plant growth and overcoming metal stress.


Assuntos
Bacillus , Metais Pesados , Poluentes do Solo , Triticum/genética , Níquel/toxicidade , Níquel/metabolismo , Fosfatos/metabolismo , RNA Ribossômico 16S/genética , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Zinco/metabolismo , Bactérias/metabolismo , Solo , Poluentes do Solo/metabolismo
20.
PLoS Genet ; 20(2): e1011135, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38315718

RESUMO

Phosphorus (P) deficiency is one of the most critical factors for plant growth and productivity, including its inhibition of lateral root initiation. Auxin response factors (ARFs) play crucial roles in root development via auxin signaling mediated by genetic pathways. In this study, we found that the transcription factor ZmARF1 was associated with low inorganic phosphate (Pi) stress-related traits in maize. This superior root morphology and greater phosphate stress tolerance could be ascribed to the overexpression of ZmARF1. The knock out mutant zmarf1 had shorter primary roots, fewer root tip number, and lower root volume and surface area. Transcriptomic data indicate that ZmLBD1, a direct downstream target gene, is involved in lateral root development, which enhances phosphate starvation tolerance. A transcriptional activation assay revealed that ZmARF1 specifically binds to the GC-box motif in the promoter of ZmLBD1 and activates its expression. Moreover, ZmARF1 positively regulates the expression of ZmPHR1, ZmPHT1;2, and ZmPHO2, which are key transporters of Pi in maize. We propose that ZmARF1 promotes the transcription of ZmLBD1 to modulate lateral root development and Pi-starvation induced (PSI) genes to regulate phosphate mobilization and homeostasis under phosphorus starvation. In addition, ZmERF2 specifically binds to the ABRE motif of the promoter of ZmARF1 and represses its expression. Collectively, the findings of this study revealed that ZmARF1 is a pivotal factor that modulates root development and confers low-Pi stress tolerance through the transcriptional regulation of the biological function of ZmLBD1 and the expression of key Pi transport proteins.


Assuntos
Fosfatos , Zea mays , Fosfatos/metabolismo , Fósforo/metabolismo , Ácidos Indolacéticos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Raízes de Plantas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
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