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2. Physiological and modulatory role of thioredoxins in the cellular function

Author

Xinastle-Castillo Luis Omar and Landa Abraham

Subjects
redox state, s-nitrosylation, signaling cascade, immune response, transcription factor, Medicine
Abstract

Thioredoxins (TRXs) are a class of ubiquitous and multifunctional protein. Mammal cells present three isoforms: a cytosolic and extracellular called thioredoxin 1 (TRX1), a mitochondrial (TRX2), and one specific in spermatozoids (TRX3). Besides, a truncated form called TRX80 exists, which results from the post-translational cleavage performed on TRX1. TRXs’ main function is to maintain the reduction–oxidation homeostasis of the cell, reducing the proteins through a thiol-disulfide exchange that depends on two cysteines located in the active site of the protein (Cys32-X-X-Cys35 in humans). In addition, TRX1 performs S-nitrosylation, a post-translational modification of proteins that depends on cysteines of its C-terminal region (Cys62, Cys69, and Cys73 in human TRX1). These modifications allow the TRXs to modulate the protein function and participate in regulating diverse cellular processes, such as oxidative stress, transcription, signaling cascades, apoptosis, inflammation, and immunologic response. This points out the crucial relevance of TRXs for cell function, signaling it as a strategic target for the treatment of many diseases and its possible use as a therapeutic factor.

Published
2022
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4. Taenia solium TAF6 and TAF9 bind to a downstream promoter element present in the Tstbp1 gene core promoter.

Author

Rodríguez-Lima, Oscar, García-Gutiérrez, Ponciano, Jiménez, Lucía, Velázquez-Villegas, Laura A., Zarain-Herzberg, Angel, Lazzarini, Roberto, Estrada, Karel, and Landa, Abraham

Subjects
TAENIA solium, BINDING sites, GENE expression, MOLECULAR dynamics, TRANSCRIPTION factors
Abstract

Transcription regulation in cestodes has been little studied. Here, we characterize the Taenia solium TATA-binding protein (TBP) gene. We found binding sites for transcription factors such as NF1, YY1, and AP-1 in the proximal promoter. We also identified two TATA-like elements in the promoter; however, neither could bind TBP. Additionally, we mapped the transcription start site (A+1) within an initiator and identified a putative downstream promoter element (DPE) located at +27 bp relative to the transcription start site. These two elements are important and functional for gene expression. Moreover, we identified the genes encoding T. solium TBP-Associated Factor 6 (TsTAF6) and 9 (TsTAF9). A Western blot assay revealed that both factors are expressed in the parasite; electrophoretic mobility shift assays and super-shift assays revealed interactions between the DPE probe and TsTAF6-TsTAF9. Finally, we used molecular dynamics simulations to formulate an interaction model among TsTAF6, TsTAF9, and the DPE probe; we stabilized the model with interactions between the histone fold domain pair in TAFs and several pairs of nucleotides in the DPE probe. We discuss novel and interesting features of the TsTAF6-TsTAF9 complex for interaction with DPE on T. solium promoters. [ABSTRACT FROM AUTHOR]

Published
2024
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8. Biochemical characterization and gene structure analysis of the 24‐kDa glutathione transferase sigma from Taenia solium.

Author

Miranda‐Blancas, Ricardo, Rodríguez‐Lima, Oscar, García‐Gutiérrez, Ponciano, Flores‐López, Roberto, Jiménez, Lucía, Zubillaga, Rafael A., Rudiño‐Piñera, Enrique, and Landa, Abraham

Subjects
TAENIA solium, GLUTATHIONE transferase, CYSTICERCOSIS, MENTAL illness, BINDING sites, ENZYME stability
Abstract

Taenia solium can cause human taeniasis and/or cysticercosis. The latter can in some instances cause human neurocysticercosis which is considered a priority in disease‐control strategies and the prevention of mental health problems. Glutathione transferases are crucial for the establishment and long‐term survival of T. solium; therefore, we structurally analyzed the 24‐kDa glutathione transferase gene (Ts24gst) of T. solium and biochemically characterized its product. The gene promoter showed potential binding sites for transcription factors and xenobiotic regulatory elements. The gene consists of a transcription start site, four exons split by three introns, and a polyadenylation site. The gene architecture is conserved in cestodes. Recombinant Ts24GST (rTs24GST) was active and dimeric. Anti‐rTs24GST serum showed slight cross‐reactivity with human sigma‐class GST. A 3D model of Ts24GST enabled identification of putative residues involved in interactions of the G‐site with GSH and of the H‐site with CDNB and prostaglandin D2. Furthermore, rTs24GST showed optimal activity at 45 °C and pH 9, as well as high structural stability in a wide range of temperatures and pHs. These results contribute to the better understanding of this parasite and the efforts directed to fight taeniasis/cysticercosis. [ABSTRACT FROM AUTHOR]

Published
2024
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9. Neuroprotection of Thioredoxin1 in the brain

Author

Navarro, Luz, primary, Noriega-Navarro, Roxana, additional, Martínez-Tapia, Ricardo J., additional, Osornio-Hernández, Juan L., additional, Landa-Navarro, Lucia, additional, Xinastle-Castillo, Luis O., additional, and Landa, Abraham, additional

Published
2023
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11. The effect of thioredoxin‐1 in a rat model of traumatic brain injury depending on diurnal variation

Author

Noriega‐Navarro, Roxana, primary, Martínez‐Tapia, Ricardo Jesús, additional, González‐Rivera, Rubén, additional, Ochoa‐Sánchez, Alicia, additional, Abarca‐Magaña, Julio César, additional, Landa‐Navarro, Lucía, additional, Rodríguez‐Mata, Verónica, additional, Ugalde‐Muñiz, Perla, additional, Pérez‐Torres, Armando, additional, Landa, Abraham, additional, and Navarro, Luz, additional

Published
2023
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20. The genomes of four tapeworm species reveal adaptations to parasitism

Author

Tsai, Isheng J., Zarowiecki, Magdalena, Holroyd, Nancy, Garciarrubio, Alejandro, Sanchez-Flores, Alejandro, Brooks, Karen L., Tracey, Alan, Bobes, Raúl J., Fragoso, Gladis, Sciutto, Edda, Aslett, Martin, Beasley, Helen, Bennett, Hayley M., Cai, Jianping, Camicia, Federico, Clark, Richard, Cucher, Marcela, De Silva, Nishadi, Day, Tim A., Deplazes, Peter, Estrada, Karel, Fernández, Cecilia, Holland, Peter W. H., Hou, Junling, Hu, Songnian, Huckvale, Thomas, Hung, Stacy S., Kamenetzky, Laura, Keane, Jacqueline A., Kiss, Ferenc, Koziol, Uriel, Lambert, Olivia, Liu, Kan, Luo, Xuenong, Luo, Yingfeng, Macchiaroli, Natalia, Nichol, Sarah, Paps, Jordi, Parkinson, John, Pouchkina-Stantcheva, Natasha, Riddiford, Nick, Rosenzvit, Mara, Salinas, Gustavo, Wasmuth, James D., Zamanian, Mostafa, Zheng, Yadong, Sánchez-Flores, Alejandro, Cevallos, Miguel A., Morett, Enrique, González, Víctor, Portillo, Tobias, Ochoa-Leyva, Adrian, José, Marco V., Landa, Abraham, Jiménez, Lucía, Valdés, Víctor, Carrero, Julio C., Larralde, Carlos, Morales-Montor, Jorge, Limón-Lason, Jorge, Soberón, Xavier, Laclette, Juan P., Cai, Xuepeng, Olson, Peter D., Brehm, Klaus, and Berriman, Matthew

Published
2013
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23. Development of New Drugs to Treat <em>Taenia solium</em> Cysticercosis : Targeting 26 kDa Glutathione Transferase

Author

Landa, Abraham, Zubillaga, Rafael A., Jiménez, Lucía, and García-Gutiérrez, Ponciano

Subjects
Medical
Abstract

Taenia solium causes neurocysticercosis, a parasitic infection of the central nervous system in humans. The costs of management, treatment, and diagnosis of patients with neurocysticercosis are high, and some patients do not respond to the currently available treatments. Helminth cytosolic glutathione transferases (GSTs) are essential enzymes involved in the regulation of immune responses, transport, and detoxification. In T. solium, three cytosolic GSTs with molecular masses of 26.5 (Ts26GST), 25.5 (Ts25GST), and 24.3 kDa (TsMσGST), classified as mu-alpha, mu and sigma GST-classes, respectively, constitute the main detoxification system, and they may be immune targets for the development of vaccines and new anthelmintics. We performed a successful virtual screen, and identified I7, a novel selective inhibitor of Ts26GST that showed a non-competitive inhibition mechanism towards substrate glutathione with a Ki of 55.7 mM and mixed inhibition towards the electrophilic substrate 1-chloro-2,4-dinitrobenzene with a Ki of 8.64 mM. Docking simulation studies showed that I7 can bind to a site that is adjacent to the electrophilic site and the furthest from the glutathione site. This new inhibitor of Ts26GST will be used as a lead molecule to develop new effective and safe drugs against diseases caused by T. solium.

Published
2018

27. Triosephosphate isomerase of Taenia solium (TTPI): phage display and antibodies as tools for finding target regions to inhibit catalytic activity

Author

Iaraset Belmont, Víctor Sanabria-Ayala, and Landa Abraham

Subjects
Phage display, Amino Acid Motifs, Molecular Sequence Data, Antibodies, Helminth, Epitope, Triosephosphate isomerase, Epitopes, Taenia solium, medicine, Animals, Amino Acid Sequence, Peptide sequence, General Veterinary, biology, Mimotope, General Medicine, Molecular biology, medicine.drug_formulation_ingredient, Infectious Diseases, Polyclonal antibodies, Insect Science, biology.protein, Parasitology, Rabbits, Antibody, Cell Surface Display Techniques, Peptides, Sequence Alignment, Triose-Phosphate Isomerase
Abstract

Previous studies demonstrated that antibodies against triosephosphate isomerase of Taenia solium (TTPI) can alter its enzymatic catalysis. In the present study, we used antibodies produced against the NH2-terminal region of TTPI (1/3NH2TTPI) and the phage display technology to find target regions to inhibit TTPI activity. As a first step, we obtained polyclonal antibodies against non-conserved regions from the 1/3NH2TTPI, which had an inhibitory effect of about 74 % on catalytic activity. Afterward, they were used to screen a library of phage-displayed dodecapeptides; as a result, 41 phage mimotope clones were isolated and grouped according to their amino acid sequence, finding the consensus A1 (VPTXPI), A2 (VPTXXI), B (LTPGQ), and D (DPLPR). Antibodies against selected phage mimotope clones were obtained by rabbit's immunization; these ones clearly recognized TTPI by both Western blot and ELISA. However, only the mimotope PDTS16 (DSVTPTSVMAVA) clone, which belongs to the VPTXXI consensus, raised antibodies capable of inhibiting the TTPI catalytic activity in 45 %. Anti-PDTS16 antibodies were confronted to several synthetic peptides that encompass the 1/3NH2TTPI, and they only recognized three, which share the motif FDTLQK belonging to the helix-α1 in TTPI. This suggests that this motif is the main part of the epitope recognized by anti-PDTS16 antibodies and revealed its importance for TTPI catalysis.

Published
2014

31. Characterization of a monoclonal antibody that specifically inhibits triosephosphate isomerase activity of Taenia solium

Author

Zavala-Carballo Araceli, Medina-Flores Yolanda, Landa Abraham, Jiménez Lucía, and Sanabria-Ayala Víctor

Subjects
Phage display, medicine.drug_class, Immunology, Molecular Sequence Data, Monoclonal antibody, Epitope, Triosephosphate isomerase, Epitopes, Immunoglobulin Fab Fragments, Mice, Taenia solium, medicine, Animals, Amino Acid Sequence, Binding site, Mice, Inbred BALB C, Hybridomas, biology, Mimotope, Antibodies, Monoclonal, General Medicine, Molecular biology, medicine.drug_formulation_ingredient, Infectious Diseases, biology.protein, Parasitology, Antibody, Triose-Phosphate Isomerase
Abstract

In the present study, we obtained and characterized partially a monoclonal antibody (4H11D10B11 mAb) against triosephosphate isomerase from Taenia solium (TTPI). This antibody recognized the enzyme by both ELISA and western blot and was able to inhibit its enzymatic activity in 74%. Moreover, the antigen-binding fragments (Fabs), products of digestion of the monoclonal antibody with papain, retained almost the same inhibitory effect. We determined the binding site by ELISA; synthetic peptides containing sequences from different non-conserved regions of the TTPI were confronted to the 4H11D10B11 mAb. The epitope recognized by the monoclonal antibody was located on peptide TTPI-56 (ATPAQAQEVHKVVRDWIRKHVDAGIADKARI), and an analysis of mimotopes, obtained with the 4H11D10B11 mAb, suggests that the epitope spans the sequence WIRKHVDAGIAD, residues 193–204 of the enzyme. This epitope is located within helix 6, next to loop 6, an essential active loop during catalysis. The antibody did not recognize triosephosphate isomerase from man and pig, definitive and intermediary hosts of T. solium, respectively. Furthermore, it did not bind to the catalytic site, since kinetic analysis demonstrated that inhibition had a non-competitive profile.

Published
2012

35. Identification of Immunodominant Peptides from Gnathostoma binucleatum

Author

Campista-León, Samuel, primary, Delgado-Vargas, Francisco, additional, Ríos-Sicairos, Julian, additional, Landa, Abraham, additional, Willms, Kaethe, additional, Bojórquez-Contreras, Ángel Noel, additional, Díaz-Camacho, Sylvia Páz, additional, López-Moreno, Hector Samuel, additional, and Mendoza-Hernández, Guillermo, additional

Published
2012
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44. Characterization of a Thioredoxin-1 Gene from Taenia solium and Its Encoding Product.

Author

Jiménez, Lucía, Rodríguez-Lima, Oscar, Ochoa-Sánchez, Alicia, and Landa, Abraham

Subjects
DNA analysis, AMINO acids, ANIMAL experimentation, TAPEWORMS, ESCHERICHIA coli, GENES, GENETIC techniques, IMMUNOGLOBULINS, INSECT larvae, OXIDOREDUCTASES, POLYMERASE chain reaction, RABBITS, TEMPERATURE, WESTERN immunoblotting, GENOMICS, REVERSE transcriptase polymerase chain reaction, MEDICAL coding, IN vitro studies
Abstract

Taenia solium thioredoxin-1 gene (TsTrx-1) has a length of 771 bp with three exons and two introns. The core promoter gene presents two putative stress transcription factor binding sites, one putative TATA box, and a transcription start site (TSS). TsTrx-1 mRNA is expressed higher in larvae than in adult. This gene encodes a protein of 107 amino acids that presents the Trx active site (CGPC), the classical secondary structure of the thioredoxin fold, and the highest degree of identity with the Echinococcus granulosus Trx. A recombinant TsTrx-1 (rTsTrx-1) was produced in Escherichia coli with redox activity. Optimal activity for rTsTrx-1 was at pH 6.5 in the range of 15 to 25°C. The enzyme conserved activity for 3 h and lost it in 24 h at 37°C. rTsTrx-1 lost 50% activity after 1 h and lost activity completely in 24 h at temperatures higher than 55°C. Best storage temperature for rTsTrx-1 was at −70°C. It was inhibited by high concentrations of H2O2 and methylglyoxal (MG), but it was inhibited neither by NaCl nor by anti-rTsTrx-1 rabbit antibodies that strongly recognized a ~12 kDa band in extracts from several parasites. These TsTrx-1 properties open the opportunity to study its role in relationship T. solium-hosts. [ABSTRACT FROM AUTHOR]

Published
2015
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46. The genome project of Taenia solium

Author

Aguilar-Díaz, Hugo, primary, Bobes, Raúl J., additional, Carrero, Julio C., additional, Camacho-Carranza, Rafael, additional, Cervantes, Claudia, additional, Cevallos, Miguel A., additional, Dávila, Guillermo, additional, Rodríguez-Dorantes, Mauricio, additional, Escobedo, Galileo, additional, Fernández, José Luis, additional, Fragoso, Gladis, additional, Gaytán, Paul, additional, Garciarubio, Alejandro, additional, González, Victor M., additional, González, Lorena, additional, José, Marco V., additional, Jiménez, Lucía, additional, Laclette, Juan P., additional, Landa, Abraham, additional, Larralde, Carlos, additional, Morales-Montor, Jorge, additional, Morett, Enrique, additional, Ostoa-Saloma, Pedro, additional, Sciutto, Edda, additional, Santamaría, Rosa I., additional, Soberón, Xavier, additional, de la Torre, Patricia, additional, Valdés, Víctor, additional, and Yánez, Jorge, additional

Published
2006
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