Comparative analyses of transcriptional responses of Dectes texanus LeConte (Coleoptera: Cerambycidae) larvae fed on three different host plants and artificial diet

AbstractDectes texanus is an important coleopteran pest of soybeans and cultivated sunflowers in the Midwestern United States that causes yield losses by girdling stems of their host plants. Although sunflower and giant ragweed are primary hosts of D. texanus, they began colonizing soybeans approximately 50 years ago and no reliable management method has been established to prevent or reduce losses by this pest. To identify genes putatively involved when feeding soybean, we compared gene expression of D. texanus third-instar larvae fed soybean to those fed sunflower, giant ragweed, or artificial diet. Dectes texanus larvae differentially expressed 514 unigenes when fed on soybean compared to those fed the other diet treatments. Enrichment analyses of gene ontology terms from up-regulated unigenes in soybean-fed larvae compared to those fed both primary hosts highlighted unigenes involved in oxidoreductase and polygalacturonase activities. Cytochrome P450s, carboxylesterases, major facilitator superfamily transporters, lipocalins, apolipoproteins, glycoside hydrolases 1 and 28, and lytic monooxygenases were among the most commonly up-regulated unigenes in soybean-fed larvae compared to those fed their primary hosts. These results suggest that D. texanus larvae differentially expressed unigenes involved in biotransformation of allelochemicals, digestion of plant cell walls and transport of small solutes and lipids when feeding in soybean.

Download Full-text

Discovery of β-1,4-d-Mannosyl-N-acetyl-d-glucosamine Phosphorylase Involved in the Metabolism of N-Glycans

Journal of Biological Chemistry ◽

10.1074/jbc.m113.469080 ◽

2013 ◽

Vol 288 (38) ◽

pp. 27366-27374 ◽

Cited By ~ 44

Author(s):

Takanori Nihira ◽

Erika Suzuki ◽

Motomitsu Kitaoka ◽

Mamoru Nishimoto ◽

Ken'ichi Ohtsubo ◽

...

Keyword(s):

Gene Cluster ◽

Metabolic Pathway ◽

Anaerobic Bacteria ◽

Major Facilitator Superfamily ◽

Glycoside Hydrolases ◽

Mannose Residue ◽

Key Enzyme ◽

Major Facilitator Superfamily Transporter ◽

Catalyzed Reactions ◽

Major Facilitator

A gene cluster involved in N-glycan metabolism was identified in the genome of Bacteroides thetaiotaomicron VPI-5482. This gene cluster encodes a major facilitator superfamily transporter, a starch utilization system-like transporter consisting of a TonB-dependent oligosaccharide transporter and an outer membrane lipoprotein, four glycoside hydrolases (α-mannosidase, β-N-acetylhexosaminidase, exo-α-sialidase, and endo-β-N-acetylglucosaminidase), and a phosphorylase (BT1033) with unknown function. It was demonstrated that BT1033 catalyzed the reversible phosphorolysis of β-1,4-d-mannosyl-N-acetyl-d-glucosamine in a typical sequential Bi Bi mechanism. These results indicate that BT1033 plays a crucial role as a key enzyme in the N-glycan catabolism where β-1,4-d-mannosyl-N-acetyl-d-glucosamine is liberated from N-glycans by sequential glycoside hydrolase-catalyzed reactions, transported into the cell, and intracellularly converted into α-d-mannose 1-phosphate and N-acetyl-d-glucosamine. In addition, intestinal anaerobic bacteria such as Bacteroides fragilis, Bacteroides helcogenes, Bacteroides salanitronis, Bacteroides vulgatus, Prevotella denticola, Prevotella dentalis, Prevotella melaninogenica, Parabacteroides distasonis, and Alistipes finegoldii were also suggested to possess the similar metabolic pathway for N-glycans. A notable feature of the new metabolic pathway for N-glycans is the more efficient use of ATP-stored energy, in comparison with the conventional pathway where β-mannosidase and ATP-dependent hexokinase participate, because it is possible to directly phosphorylate the d-mannose residue of β-1,4-d-mannosyl-N-acetyl-d-glucosamine to enter glycolysis. This is the first report of a metabolic pathway for N-glycans that includes a phosphorylase. We propose 4-O-β-d-mannopyranosyl-N-acetyl-d-glucosamine:phosphate α-d-mannosyltransferase as the systematic name and β-1,4-d-mannosyl-N-acetyl-d-glucosamine phosphorylase as the short name for BT1033.

Download Full-text

Dual transcriptional analysis of Peronospora belbahrii and Ocimum basilicum in susceptible interactions

10.1101/2021.09.07.457810 ◽

2021 ◽

Author(s):

Eric T. Johnson ◽

Hye-Seon Kim ◽

Miaoying Tian ◽

Nativ Dudai ◽

Ofir Tal ◽

...

Keyword(s):

Downy Mildew ◽

Enrichment Analysis ◽

Ocimum Basilicum ◽

Infection Process ◽

Glycoside Hydrolases ◽

Differentially Expressed ◽

Transcriptional Analysis ◽

Time Interval ◽

Plant Cell Walls ◽

Severity Of The Disease

AbstractBasil downy mildew, caused by the pathogen Peronospora belbahrii, is a major problem for sweet basil growers worldwide. The genome sequences of both Ocimum basilicum and P. belbahrii were recently completed but extensive transcriptome analysis of this pathosystem has not been completed. RNA sequencing was performed using basil leaf samples collected three and six days after inoculation with sporangia from an Illinois isolate of P. belbahrii and differentially expressed genes were identified. Gene enrichment analysis identified 22 genes that were upregulated at day three, in comparison to mock inoculated leaf samples, that were classified as ‘defense response to oomycetes’; among this group were five orthologues of Arabidopsis thaliana DOWNY MILDEW RESISTANCE 6. During the same time interval, many genes contributing to photosynthesis in the infected leaves were downregulated in comparison to control leaf samples. Many more genes were differentially expressed in the inoculated basil leaves at day six, compared to mock inoculated leaves, as the pathogen began to produce sporangiophores. On days three and six, the pathogen produced high transcript levels of secreted glycoside hydrolases, which likely release sugars from the plant cell walls needed for the growth of the pathogen. These results contribute to a better understanding of the infection process of downy mildew and will aid the development of more effective measures for reducing the severity of the disease.

Download Full-text

Untargeted Metabolomics Uncovers the Essential Lysine Transporter in Toxoplasma gondii

Metabolites ◽

10.3390/metabo11080476 ◽

2021 ◽

Vol 11 (8) ◽

pp. 476

Author(s):

Joachim Kloehn ◽

Matteo Lunghi ◽

Emmanuel Varesio ◽

David Dubois ◽

Dominique Soldati-Favre

Keyword(s):

Amino Acids ◽

Toxoplasma Gondii ◽

Rna Degradation ◽

Major Facilitator Superfamily ◽

Untargeted Metabolomics ◽

Apicomplexan Parasites ◽

Obligate Intracellular ◽

Intracellular Parasites ◽

Major Facilitator ◽

Plasma Membrane Transporter

Apicomplexan parasites are responsible for devastating diseases, including malaria, toxoplasmosis, and cryptosporidiosis. Current treatments are limited by emerging resistance to, as well as the high cost and toxicity of existing drugs. As obligate intracellular parasites, apicomplexans rely on the uptake of many essential metabolites from their host. Toxoplasma gondii, the causative agent of toxoplasmosis, is auxotrophic for several metabolites, including sugars (e.g., myo-inositol), amino acids (e.g., tyrosine), lipidic compounds and lipid precursors (cholesterol, choline), vitamins, cofactors (thiamine) and others. To date, only few apicomplexan metabolite transporters have been characterized and assigned a substrate. Here, we set out to investigate whether untargeted metabolomics can be used to identify the substrate of an uncharacterized transporter. Based on existing genome- and proteome-wide datasets, we have identified an essential plasma membrane transporter of the major facilitator superfamily in T. gondii—previously termed TgApiAT6-1. Using an inducible system based on RNA degradation, TgApiAT6-1 was depleted, and the mutant parasite’s metabolome was compared to that of non-depleted parasites. The most significantly reduced metabolite in parasites depleted in TgApiAT6-1 was identified as the amino acid lysine, for which T. gondii is predicted to be auxotrophic. Using stable isotope-labeled amino acids, we confirmed that TgApiAT6-1 is required for efficient lysine uptake. Our findings highlight untargeted metabolomics as a powerful tool to identify the substrate of orphan transporters.

Download Full-text

Structural basis of inhibition of a transporter from Staphylococcus aureus, NorC, through a single-domain camelid antibody

Communications Biology ◽

10.1038/s42003-021-02357-x ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Sushant Kumar ◽

Arunabh Athreya ◽

Ashutosh Gulati ◽

Rahul Mony Nair ◽

Ithayaraja Mahendran ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Pathogenic Bacteria ◽

Major Facilitator Superfamily ◽

Single Domain ◽

Fluoroquinolone Resistance ◽

Structural Basis ◽

Antibody Complex ◽

Complementarity Determining Regions ◽

Major Facilitator ◽

Alternating Access

AbstractTransporters play vital roles in acquiring antimicrobial resistance among pathogenic bacteria. In this study, we report the X-ray structure of NorC, a 14-transmembrane major facilitator superfamily member that is implicated in fluoroquinolone resistance in drug-resistant Staphylococcus aureus strains, at a resolution of 3.6 Å. The NorC structure was determined in complex with a single-domain camelid antibody that interacts at the extracellular face of the transporter and stabilizes it in an outward-open conformation. The complementarity determining regions of the antibody enter and block solvent access to the interior of the vestibule, thereby inhibiting alternating-access. NorC specifically interacts with an organic cation, tetraphenylphosphonium, although it does not demonstrate an ability to transport it. The interaction is compromised in the presence of NorC-antibody complex, consequently establishing a strategy to detect and block NorC and related transporters through the use of single-domain camelid antibodies.

Download Full-text

Comparing transcriptional responses to Fusarium crown rot in wheat and barley identified an important relationship between disease resistance and drought tolerance

BMC Plant Biology ◽

10.1186/s12870-020-02818-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Z. Y. Su ◽

J. J. Powell ◽

S. Gao ◽

M. Zhou ◽

C. Liu

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Crown Rot ◽

Differentially Expressed ◽

Transcriptional Responses ◽

Drought Treatment ◽

Crop Species ◽

Fusarium Crown Rot ◽

Important Relationship ◽

The Impact

Abstract Background Fusarium crown rot (FCR) is a chronic disease in cereal production worldwide. The impact of this disease is highly environmentally dependant and significant yield losses occur mainly in drought-affected crops. Results In the study reported here, we evaluated possible relationships between genes conferring FCR resistance and drought tolerance using two approaches. The first approach studied FCR induced differentially expressed genes (DEGs) targeting two barley and one wheat loci against a panel of genes curated from the literature based on known functions in drought tolerance. Of the 149 curated genes, 61.0% were responsive to FCR infection across the three loci. The second approach was a comparison of the global DEGs induced by FCR infection with the global transcriptomic responses under drought in wheat. This analysis found that approximately 48.0% of the DEGs detected one week following drought treatment and 74.4% of the DEGs detected three weeks following drought treatment were also differentially expressed between the susceptible and resistant isolines under FCR infection at one or more timepoints. As for the results from the first approach, the vast majority of common DEGs were downregulated under drought and expressed more highly in the resistant isoline than the sensitive isoline under FCR infection. Conclusions Results from this study suggest that the resistant isoline in wheat was experiencing less drought stress, which could contribute to the stronger defence response than the sensitive isoline. However, most of the genes induced by drought stress in barley were more highly expressed in the susceptible isolines than the resistant isolines under infection, indicating that genes conferring drought tolerance and FCR resistance may interact differently between these two crop species. Nevertheless, the strong relationship between FCR resistance and drought responsiveness provides further evidence indicating the possibility to enhance FCR resistance by manipulating genes conferring drought tolerance.

Download Full-text

calderon encodes an organic cation transporter of the major facilitator superfamily required for cell growth and proliferation of Drosophila tissues

Development ◽

10.1242/dev.02436 ◽

2006 ◽

Vol 133 (14) ◽

pp. 2617-2625 ◽

Cited By ~ 10

Author(s):

H. Herranz

Keyword(s):

Cell Growth ◽

Organic Cation ◽

Organic Cation Transporter ◽

Major Facilitator Superfamily ◽

Major Facilitator ◽

Cell Growth And Proliferation

Download Full-text

Reproductive performance and transcriptome analyses of Tetranychus urticae when feeding on bean leaves and an artificial diet

Systematic and Applied Acarology ◽

10.11158/saa.24.7.11 ◽

2019 ◽

Vol 24 (7) ◽

pp. 1272-1283

Author(s):

Yongjuan He ◽

Jiale Lv ◽

Endong Wang ◽

Xuenong Xu

Keyword(s):

Tetranychus Urticae ◽

Artificial Diet ◽

Mass Rearing ◽

Differentially Expressed ◽

Detoxification Enzymes ◽

Adult Longevity ◽

Natural Food ◽

Leaf Extracts ◽

Transcriptome Analyses ◽

Bean Leaves

As an important pest, Tetranychus urticae fed on thousands of host plants and showed strong capability in host adaptation. However, hardly any success artificial diet has been developed for it. In this study, we compared adult longevity and reproduction of T. urticae that fed on its natural food (bean leaves) and an artificial diet with leaf extracts added, and tried to investigate the reason why the artificial diet was inefficient through transcriptome analyses. Mean adult longevity and cumulative fecundities of T. urticae was reduced by 53.4% and 93.8%, respectively. Transcriptome analyses showed that 1731 genes were differentially expressed comparing individuals fed with the artificial diet and with their natural food, among which most (77.1%) were down regulated. No significant induced expression of xenobiotic transporters and detoxification enzymes were observed when T. urticae were fed with the artificial diet. In contrast, differentially expressed genes were mainly enriched in digestive related terms, especially in lipid metabolism related pathways, with most genes down regulated. Our results indicated the significance in further investigating lipid demand and metabolism of T. urticae to improve its mass rearing techniques.

Download Full-text

Establishment of a Genetic Transformation System in Guanophilic Fungus Amphichorda guana

Journal of Fungi ◽

10.3390/jof7020138 ◽

2021 ◽

Vol 7 (2) ◽

pp. 138

Author(s):

Min Liang ◽

Wei Li ◽

Landa Qi ◽

Guocan Chen ◽

Lei Cai ◽

...

Keyword(s):

Genetic Transformation ◽

Genetic Manipulation ◽

Major Facilitator Superfamily ◽

Protoplast Regeneration ◽

Transformation System ◽

Regeneration Rate ◽

Bioactive Natural Products ◽

Genetics Research ◽

Genetic Transformation System ◽

Major Facilitator

Fungi from unique environments exhibit special physiological characters and plenty of bioactive natural products. However, the recalcitrant genetics or poor transformation efficiencies prevent scientists from systematically studying molecular biological mechanisms and exploiting their metabolites. In this study, we targeted a guanophilic fungus Amphichorda guana LC5815 and developed a genetic transformation system. We firstly established an efficient protoplast preparing method by conditional optimization of sporulation and protoplast regeneration. The regeneration rate of the protoplast is up to about 34.6% with 0.8 M sucrose as the osmotic pressure stabilizer. To develop the genetic transformation, we used the polyethylene glycol-mediated protoplast transformation, and the testing gene AG04914 encoding a major facilitator superfamily transporter was deleted in strain LC5815, which proves the feasibility of this genetic manipulation system. Furthermore, a uridine/uracil auxotrophic strain was created by using a positive screening protocol with 5-fluoroorotic acid as a selective reagent. Finally, the genetic transformation system was successfully established in the guanophilic fungus strain LC5815, which lays the foundation for the molecular genetics research and will facilitate the exploitation of bioactive secondary metabolites in fungi.

Download Full-text

Two Distinct Major Facilitator Superfamily Drug Efflux Pumps Mediate Chloramphenicol Resistance in Streptomyces coelicolor

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00853-09 ◽

2009 ◽

Vol 53 (11) ◽

pp. 4673-4677 ◽

Cited By ~ 24

Author(s):

James J. Vecchione ◽

Blair Alexander ◽

Jason K. Sello

Keyword(s):

Efflux Pump ◽

Streptomyces Coelicolor ◽

Efflux Pumps ◽

Major Facilitator Superfamily ◽

Close Relative ◽

Gram Positive ◽

Antibacterial Drugs ◽

Chloramphenicol Resistance ◽

Drug Activity ◽

Major Facilitator

ABSTRACT Chloramphenicol, florfenicol, and thiamphenicol are used as antibacterial drugs in clinical and veterinary medicine. Two efflux pumps of the major facilitator superfamily encoded by the cmlR1 and cmlR2 genes mediate resistance to these antibiotics in Streptomyces coelicolor, a close relative of Mycobacterium tuberculosis. The transcription of both genes was observed by reverse transcription-PCR. Disruption of cmlR1 decreased the chloramphenicol MIC 1.6-fold, while disruption of cmlR2 lowered the MIC 16-fold. The chloramphenicol MIC of wild-type S. coelicolor decreased fourfold and eightfold in the presence of reserpine and Phe-Arg-β-naphthylamide, respectively. These compounds are known to potentiate the activity of some antibacterial drugs via efflux pump inhibition. While reserpine is known to potentiate drug activity against gram-positive bacteria, this is the first time that Phe-Arg-β-naphthylamide has been shown to potentiate drug activity against a gram-positive bacterium.

Download Full-text