Identification and Function of Apicoplast Glutaredoxins in Neospora caninum

Glutaredoxins (GRXs), important components of the intracellular thiol redox system, are involved in multiple cellular processes. In a previous study, we identified five GRXs in the apicomplexan parasite, Neospora caninum. In the present study, we confirmed that the GRXs S14 and C5 are located in the apicoplast, which suggests unique functions for these proteins. Although single-gene deficiency did not affect the growth of parasites, a double knockout (Δgrx S14Δgrx C5) significantly reduced their reproductive capacity. However, there were no significant changes in redox indices (GSH/GSSG ratio, reactive oxygen species and hydroxyl radical levels) in double-knockout parasites, indicating that grx S14 and grx C5 are not essential for maintaining the redox balance in parasite cells. Key amino acid mutations confirmed that the Cys203 of grx S14 and Cys253/256 of grx C5 are important for parasite growth. Based on comparative proteomics, 79 proteins were significantly downregulated in double-knockout parasites, including proteins mainly involved in the electron transport chain, the tricarboxylic acid cycle and protein translation. Collectively, GRX S14 and GRX C5 coordinate the growth of parasites. However, considering their special localization, the unique functions of GRX S14 and GRX C5 need to be further studied.

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Local Protein Translation and RNA Processing of Synaptic Proteins in Autism Spectrum Disorder

International Journal of Molecular Sciences ◽

10.3390/ijms22062811 ◽

2021 ◽

Vol 22 (6) ◽

pp. 2811

Author(s):

Yuyoung Joo ◽

David R. Benavides

Keyword(s):

Autism Spectrum Disorder ◽

Fragile X ◽

Single Gene ◽

Protein Translation ◽

Autism Spectrum ◽

Repetitive Behaviors ◽

Spectrum Disorder ◽

Synaptic Proteins ◽

Local Translation ◽

Translation Control

Autism spectrum disorder (ASD) is a heritable neurodevelopmental condition associated with impairments in social interaction, communication and repetitive behaviors. While the underlying disease mechanisms remain to be fully elucidated, dysfunction of neuronal plasticity and local translation control have emerged as key points of interest. Translation of mRNAs for critical synaptic proteins are negatively regulated by Fragile X mental retardation protein (FMRP), which is lost in the most common single-gene disorder associated with ASD. Numerous studies have shown that mRNA transport, RNA metabolism, and translation of synaptic proteins are important for neuronal health, synaptic plasticity, and learning and memory. Accordingly, dysfunction of these mechanisms may contribute to the abnormal brain function observed in individuals with autism spectrum disorder (ASD). In this review, we summarize recent studies about local translation and mRNA processing of synaptic proteins and discuss how perturbations of these processes may be related to the pathophysiology of ASD.

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Overexpression of DUF538 from Wild Arachis Enhances Plant Resistance to Meloidogyne spp.

Agronomy ◽

10.3390/agronomy11030559 ◽

2021 ◽

Vol 11 (3) ◽

pp. 559

Author(s):

Ana Claudia Guerra Araujo ◽

Patricia Messenberg Guimaraes ◽

Ana Paula Zotta Mota ◽

Larissa Arrais Guimaraes ◽

Bruna Medeiros Pereira ◽

...

Keyword(s):

Transgenic Plants ◽

Redox System ◽

Redox Balance ◽

Uncharacterized Protein ◽

Chlorophyll Breakdown ◽

Domain Of Unknown Function ◽

Expression Behavior ◽

Meloidogyne Spp ◽

Wild Peanut ◽

First Time

DUF538 proteins belong to a large group of uncharacterized protein families sharing the highly conserved Domain of Unknown Function (DUF). Attention has been given to DUF538 domain-containing proteins due to changes in their gene expression behavior and protein abundance during plant development and responses to stress. Putative roles attributed to DUF538 in plants under abiotic and biotic constraints include involvement in cell redox balance, chlorophyll breakdown and pectin degradation. Our previous transcriptome studies suggested that DUF538 is also involved in the resistance responses of wild Arachis species against the highly hazardous root-knot nematodes (RKNs). To clarify the role of the AsDUF538 gene from the wild peanut relative Arachis stenosperma in this interaction, we analyzed the effect of its overexpression on RKN infection in peanut and soybean hairy roots and Arabidopsis transgenic plants. AsDUF538 overexpression significantly reduced the infection in all three heterologous plant systems against their respective RKN counterparts. The distribution of AsDUF538 transcripts in RKN-infected Arachis roots and the effects of AsDUF538 overexpression on hormonal pathways and redox system in transgenic Arabidopsis were also evaluated. This is the first time that a DUF538 gene is functionally validated in transgenic plants and the earliest report on its role in plant defense against RKNs.

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Metabolic control of nitrogen fixation in rhizobium-legume symbioses

Science Advances ◽

10.1126/sciadv.abh2433 ◽

2021 ◽

Vol 7 (31) ◽

pp. eabh2433

Author(s):

Carolin C. M. Schulte ◽

Khushboo Borah ◽

Rachel M. Wheatley ◽

Jason J. Terpolilli ◽

Gerhard Saalbach ◽

...

Keyword(s):

Metabolic Flux ◽

Tricarboxylic Acid Cycle ◽

Oxygen Demand ◽

Metabolic Model ◽

Redox Balance ◽

Ammonia Assimilation ◽

Nodule Formation ◽

Flux Analysis ◽

Carbon And Nitrogen ◽

Genome Scale

Rhizobia induce nodule formation on legume roots and differentiate into bacteroids, which catabolize plant-derived dicarboxylates to reduce atmospheric N2 into ammonia. Despite the agricultural importance of this symbiosis, the mechanisms that govern carbon and nitrogen allocation in bacteroids and promote ammonia secretion to the plant are largely unknown. Using a metabolic model derived from genome-scale datasets, we show that carbon polymer synthesis and alanine secretion by bacteroids facilitate redox balance in microaerobic nodules. Catabolism of dicarboxylates induces not only a higher oxygen demand but also a higher NADH/NAD+ ratio than sugars. Modeling and 13C metabolic flux analysis indicate that oxygen limitation restricts the decarboxylating arm of the tricarboxylic acid cycle, which limits ammonia assimilation into glutamate. By tightly controlling oxygen supply and providing dicarboxylates as the energy and electron source donors for N2 fixation, legumes promote ammonia secretion by bacteroids. This is a defining feature of rhizobium-legume symbioses.

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Compensatory guaiacyl lignin biosynthesis at the expense of syringyl lignin in 4CL1-knockout poplar

10.1101/2019.12.20.885350 ◽

2019 ◽

Author(s):

Chung-Jui Tsai ◽

Peng Xu ◽

Liang-Jiao Xue ◽

Hao Hu ◽

Batbayar Nyamdari ◽

...

Keyword(s):

Lignin Biosynthesis ◽

Redox Balance ◽

Antioxidant Systems ◽

Activity Levels ◽

Sulfur Assimilation ◽

Syringyl Lignin ◽

Metabolic Adaptations ◽

Thiol Redox ◽

Guaiacyl Lignin ◽

Lignin Biosynthetic Pathway

AbstractThe lignin biosynthetic pathway is highly conserved in angiosperms, yet pathway manipulations give rise to a variety of taxon-specific outcomes. Knockout of lignin-associated 4-coumarate:CoA ligases (4CLs) in herbaceous species mainly reduces guaiacyl (G) lignin and enhances cell wall saccharification. Here we show that CRISPR-knockout of 4CL1 in Populus tremula × alba preferentially reduced syringyl (S) lignin, with negligible effects on biomass recalcitrance. Concordant with reduced S-lignin was downregulation of ferulate 5-hydroxylases (F5Hs). Lignification was largely sustained by 4CL5, a low-affinity paralog of 4CL1 typically with only minor xylem expression or activity. Levels of caffeate, the preferred substrate of 4CL5, increased in line with significant upregulation of caffeoyl shikimate esterase1. Upregulation of caffeoyl-CoA O-methyltransferase1 and downregulation of F5Hs are consistent with preferential funneling of 4CL5 products toward G-lignin biosynthesis at the expense of S-lignin. Thus, transcriptional and metabolic adaptations to 4CL1-knockout appear to have enabled 4CL5 catalysis at a level sufficient to sustain lignification. Finally, genes involved in sulfur assimilation, the glutathione-ascorbate cycle and various antioxidant systems were upregulated in the mutants, suggesting cascading responses to perturbed thioesterification in lignin biosynthesis.One sentence summaryKnockout of lignin-associated 4CL1 in Populus reveals a 4CL5-dependent, caffeate-modulated compensatory pathway for lignification with links to thiol redox balance and sulfur assimilation.

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Dimethyl-2-oxoglutarate improves redox balance and mitochondrial function in muscle pericytes of individuals with diabetes mellitus

Diabetologia ◽

10.1007/s00125-020-05230-4 ◽

2020 ◽

Vol 63 (10) ◽

pp. 2205-2217 ◽

Cited By ~ 2

Author(s):

Ashton Faulkner ◽

Anita Tamiato ◽

William Cathery ◽

Andrea Rampin ◽

Carlo Maria Caravaggi ◽

...

Keyword(s):

Diabetes Mellitus ◽

Mitochondrial Function ◽

Myogenic Differentiation ◽

Tricarboxylic Acid Cycle ◽

Antioxidant Properties ◽

Vascular Complications ◽

Redox Balance ◽

Metabolic Enzyme ◽

Antioxidant Systems ◽

Limb Muscles

Abstract Aims/hypothesis Treatment of vascular complications of diabetes remains inadequate. We reported that muscle pericytes (MPs) from limb muscles of vascular patients with diabetes mellitus display elevated levels of oxidative stress causing a dysfunctional phenotype. Here, we investigated whether treatment with dimethyl-2-oxoglutarate (DM-2OG), a tricarboxylic acid cycle metabolite with antioxidant properties, can restore a healthy metabolic and functional phenotype. Methods MPs were isolated from limb muscles of diabetes patients with vascular disease (D-MPs) and from non-diabetic control participants (ND-MPs). Metabolic status was assessed in untreated and DM-2OG-treated (1 mmol/l) cells using an extracellular flux analyser and anion-exchange chromatography–mass spectrometry (IC-MS/MS). Redox status was measured using commercial kits and IC-MS/MS, with antioxidant and metabolic enzyme expression assessed by quantitative RT-PCR and western blotting. Myogenic differentiation and proliferation and pericyte–endothelial interaction were assessed as functional readouts. Results D-MPs showed mitochondrial dysfunction, suppressed glycolytic activity and reduced reactive oxygen species-buffering capacity, but no suppression of antioxidant systems when compared with ND-MP controls. DM-2OG supplementation improved redox balance and mitochondrial function, without affecting glycolysis or antioxidant systems. Nonetheless, this was not enough for treated D-MPs to regain the level of proliferation and myogenic differentiation of ND-MPs. Interestingly, DM-2OG exerted a positive effect on pericyte–endothelial cell interaction in the co-culture angiogenesis assay, independent of the diabetic status. Conclusions/interpretation These novel findings support the concept of using DM-2OG supplementation to improve pericyte redox balance and mitochondrial function, while concurrently allowing for enhanced pericyte–endothelial crosstalk. Such effects may help to prevent or slow down vasculopathy in skeletal muscles of people with diabetes.

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Analysis of Arabidopsis thaliana Redox Gene Network Indicates Evolutionary Expansion of Class III Peroxidase in Plants

Scientific Reports ◽

10.1038/s41598-019-52299-y ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 5

Author(s):

Raffael Azevedo de Carvalho Oliveira ◽

Abraão Silveira de Andrade ◽

Danilo Oliveira Imparato ◽

Juliana Gabriela Silva de Lima ◽

Ricardo Victor Machado de Almeida ◽

...

Keyword(s):

Gene Network ◽

Redox System ◽

Plant Evolution ◽

Evolutionary Origin ◽

Class Iii ◽

Ros Metabolism ◽

History Of ◽

Thiol Redox ◽

Public Repositories ◽

Class Iii Peroxidases

Abstract Reactive oxygen species (ROS) are byproducts of aerobic metabolism and may cause oxidative damage to biomolecules. Plants have a complex redox system, involving enzymatic and non-enzymatic compounds. The evolutionary origin of enzymatic antioxidant defense in plants is yet unclear. Here, we describe the redox gene network for A. thaliana and investigate the evolutionary origin of this network. We gathered from public repositories 246 A. thaliana genes directly involved with ROS metabolism and proposed an A. thaliana redox gene network. Using orthology information of 238 Eukaryotes from STRINGdb, we inferred the evolutionary root of each gene to reconstruct the evolutionary history of A. thaliana antioxidant gene network. We found two interconnected clusters: one formed by SOD-related, Thiol-redox, peroxidases, and other oxido-reductase; and the other formed entirely by class III peroxidases. Each cluster emerged in different periods of evolution: the cluster formed by SOD-related, Thiol-redox, peroxidases, and other oxido-reductase emerged before opisthokonta-plant divergence; the cluster composed by class III peroxidases emerged after opisthokonta-plant divergence and therefore contained the most recent network components. According to our results, class III peroxidases are in expansion throughout plant evolution, with new orthologs emerging in each evaluated plant clade divergence.

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Comparative Proteomic Analysis of Tolerance and Adaptation of Ethanologenic Saccharomyces cerevisiae to Furfural, a Lignocellulosic Inhibitory Compound

Applied and Environmental Microbiology ◽

10.1128/aem.02594-08 ◽

2009 ◽

Vol 75 (11) ◽

pp. 3765-3776 ◽

Cited By ~ 81

Author(s):

Feng-Ming Lin ◽

Bin Qiao ◽

Ying-Jin Yuan

Keyword(s):

Saccharomyces Cerevisiae ◽

Stress Responses ◽

Tricarboxylic Acid Cycle ◽

Expression Profiles ◽

Proteome Analysis ◽

Redox Balance ◽

Central Carbon Metabolism ◽

Alcohol Dehydrogenases ◽

Reverse Transcription Pcr ◽

The Unfolded Protein Response

ABSTRACT The molecular mechanism involved in tolerance and adaptation of ethanologenic Saccharomyces cerevisiae to inhibitors (such as furfural, acetic acid, and phenol) represented in lignocellulosic hydrolysate is still unclear. Here, 18O-labeling-aided shotgun comparative proteome analysis was applied to study the global protein expression profiles of S. cerevisiae under conditions of treatment of furfural compared with furfural-free fermentation profiles. Proteins involved in glucose fermentation and/or the tricarboxylic acid cycle were upregulated in cells treated with furfural compared with the control cells, while proteins involved in glycerol biosynthesis were downregulated. Differential levels of expression of alcohol dehydrogenases were observed. On the other hand, the levels of NADH, NAD+, and NADH/NAD+ were reduced whereas the levels of ATP and ADP were increased. These observations indicate that central carbon metabolism, levels of alcohol dehydrogenases, and the redox balance may be related to tolerance of ethanologenic yeast for and adaptation to furfural. Furthermore, proteins involved in stress response, including the unfolded protein response, oxidative stress, osmotic and salt stress, DNA damage and nutrient starvation, were differentially expressed, a finding that was validated by quantitative real-time reverse transcription-PCR to further confirm that the general stress responses are essential for cellular defense against furfural. These insights into the response of yeast to the presence of furfural will benefit the design and development of inhibitor-tolerant ethanologenic yeast by metabolic engineering or synthetic biology.

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Cell calcium, vitamin E, and teh thiol redox system in cytocoxicity

Free Radical Biology and Medicine ◽

10.1016/0891-5849(89)90118-4 ◽

1989 ◽

Vol 6 (2) ◽

pp. 209-224 ◽

Cited By ~ 94

Author(s):

Gary A. Pascoe ◽

Donald J. Reed

Keyword(s):

Vitamin E ◽

Redox System ◽

Cell Calcium ◽

Thiol Redox

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The system biology of thiol redox system in Escherichia coli and yeast: Differential functions in oxidative stress, iron metabolism and DNA synthesis

FEBS Letters ◽

10.1016/j.febslet.2007.07.002 ◽

2007 ◽

Vol 581 (19) ◽

pp. 3598-3607 ◽

Cited By ~ 95

Author(s):

Michel B. Toledano ◽

Chitranshu Kumar ◽

Natacha Le Moan ◽

Dan Spector ◽

Frédérique Tacnet

Keyword(s):

Oxidative Stress ◽

Escherichia Coli ◽

Dna Synthesis ◽

Iron Metabolism ◽

System Biology ◽

Redox System ◽

Thiol Redox

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Ebsulfur Is a Benzisothiazolone Cytocidal Inhibitor Targeting the Trypanothione Reductase of Trypanosoma brucei

Journal of Biological Chemistry ◽

10.1074/jbc.m113.495101 ◽

2013 ◽

Vol 288 (38) ◽

pp. 27456-27468 ◽

Cited By ~ 32

Author(s):

Jun Lu ◽

Suman K. Vodnala ◽

Anna-Lena Gustavsson ◽

Tomas N. Gustafsson ◽

Birger Sjöberg ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Trypanosoma Brucei ◽

Mammalian Cells ◽

Reactive Oxygen ◽

Redox System ◽

Trypanothione Reductase ◽

Oxygen Species ◽

African Trypanosomiasis ◽

Thiol Redox

Trypanosoma brucei is the causing agent of African trypanosomiasis. These parasites possess a unique thiol redox system required for DNA synthesis and defense against oxidative stress. It includes trypanothione and trypanothione reductase (TryR) instead of the thioredoxin and glutaredoxin systems of mammalian hosts. Here, we show that the benzisothiazolone compound ebsulfur (EbS), a sulfur analogue of ebselen, is a potent inhibitor of T. brucei growth with a favorable selectivity index over mammalian cells. EbS inhibited the TryR activity and decreased non-protein thiol levels in cultured parasites. The inhibition of TryR by EbS was irreversible and NADPH-dependent. EbS formed a complex with TryR and caused oxidation and inactivation of the enzyme. EbS was more toxic for T. brucei than for Trypanosoma cruzi, probably due to lower levels of TryR and trypanothione in T. brucei. Furthermore, inhibition of TryR produced high intracellular reactive oxygen species. Hydrogen peroxide, known to be constitutively high in T. brucei, enhanced the EbS inhibition of TryR. The elevation of reactive oxygen species production in parasites caused by EbS induced a programmed cell death. Soluble EbS analogues were synthesized and cured T. brucei brucei infection in mice when used together with nifurtimox. Altogether, EbS and EbS analogues disrupt the trypanothione system, hampering the defense against oxidative stress. Thus, EbS is a promising lead for development of drugs against African trypanosomiasis.

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