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1.
J Infect Dis ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028664

RESUMEN

Within a multi-state viral genomic surveillance program, we evaluated whether proportions of SARS-CoV-2 infections attributed to the JN.1 variant and to XBB-lineage variants (including HV.1 and EG.5) differed between inpatient and outpatient care settings during periods of cocirculation. Both JN.1 and HV.1 were less likely than EG.5 to account for infections among inpatients versus outpatients (aOR=0.60 [95% CI: 0.43-0.84; p=0.003] and aOR=0.35 [95% CI: 0.21-0.58; p<0.001], respectively). JN.1 and HV.1 variants may be associated with a lower risk of severe illness. The severity of COVID-19 may have attenuated as predominant circulating SARS-CoV-2 lineages shifted from EG.5 to HV.1 to JN.1.

2.
Nucleic Acids Res ; 52(15): 8913-8929, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-38953168

RESUMEN

Most DNA double-strand breaks (DSBs) are harmful to genome integrity. However, some forms of DSBs are essential to biological processes, such as meiotic recombination and V(D)J recombination. DSBs are also required for programmed DNA elimination (PDE) in ciliates and nematodes. In nematodes, the DSBs are healed with telomere addition. While telomere addition sites have been well characterized, little is known regarding the DSBs that fragment nematode chromosomes. Here, we used embryos from the human and pig parasitic nematode Ascaris to characterize the DSBs. Using END-seq, we demonstrate that DSBs are introduced before mitosis, followed by extensive end resection. The resection profile is unique for each break site, and the resection generates 3'-overhangs before the addition of neotelomeres. Interestingly, telomere healing occurs much more frequently on retained DSB ends than on eliminated ends. This biased repair of the DSB ends may be due to the sequestration of the eliminated DNA into micronuclei, preventing neotelomere formation at their ends. Additional DNA breaks occur within the eliminated DNA in both Ascaris and Parascaris, ensuring chromosomal breakage and providing a fail-safe mechanism for PDE. Overall, our data indicate that telomere healing of DSBs is specific to the break sites responsible for nematode PDE.


Asunto(s)
Roturas del ADN de Doble Cadena , Telómero , Animales , Telómero/metabolismo , Telómero/genética , Reparación del ADN , Ascaris/genética , Humanos , ADN de Helmintos/genética , Porcinos , Mitosis/genética
3.
bioRxiv ; 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38559121

RESUMEN

Most DNA double-strand breaks (DSBs) are harmful to genome integrity. However, some forms of DSBs are essential to biological processes, such as meiotic recombination and V(D)J recombination. DSBs are also required for programmed DNA elimination (PDE) in ciliates and nematodes. In nematodes, the DSBs are healed with telomere addition. While telomere addition sites have been well-characterized, little is known regarding the DSBs that fragment nematode chromosomes. Here, we used embryos from the nematode Ascaris to study the timing of PDE breaks and examine the DSBs and their end processing. Using END-seq, we characterize the DSB ends and demonstrate that DNA breaks are introduced before mitosis, followed by extensive end resection. The resection profile is unique for each break site, and the resection generates 3' overhangs before the addition of telomeres. Interestingly, telomere healing occurs much more frequently on retained DSB ends than on eliminated ends. This biased repair of the DSB ends in Ascaris may be due to the sequestration of the eliminated DNA into micronuclei, preventing their ends from telomere healing. Additional DNA breaks occur within the eliminated DNA in both Ascaris and Parascaris, ensuring chromosomal breakage and providing a fail-safe mechanism for nematode PDE.

5.
BMJ Open Qual ; 12(2)2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37019468

RESUMEN

Clinical classification systems have proliferated since the APGAR score was introduced in 1953. Numerical scores and classification systems enable qualitative clinical descriptors to be transformed into categorical data, with both clinical utility and ability to provide a common language for learning. The clarity of classification rubrics embedded in a mortality classification system provides the shared basis for discussion and comparison of results. Mortality audits have been long seen as learning tools, but have tended to be siloed within a department and driven by individual learner need. We suggest that the learning needs of the system are also important. Therefore, the ability to learn from small mistakes and problems, rather than just from serious adverse events, remains facilitated.We describe a mortality classification system developed for use in the low-resource context and how it is 'fit for purpose,' able to drive both individual trainee, departmental and system learning. The utility of this classification system is that it addresses the low-resource context, including relevant factors such as limited prehospital emergency care, delayed presentation, and resource constraints. We describe five categories: (1) anticipated death or complication following terminal illness; (2) expected death or complication given clinical situation, despite taking preventive measures; (3) unexpected death or complication, not reasonably preventable; (4) potentially preventable death or complication: quality or systems issues identified and (5) unexpected death or complication resulting from medical intervention. We document how this classification system has driven learning at the individual trainee level, the departmental level, supported cross learning between departments and is being integrated into a comprehensive system-wide learning tool.


Asunto(s)
Servicios Médicos de Urgencia , Humanos , Kenia , Cuidados Paliativos , Hospitales
8.
Front Immunol ; 13: 794684, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720386

RESUMEN

Immunotherapies such as checkpoint blockade therapies are known to enhance anti-melanoma CD8+ T cell immunity, but only a fraction of patients treated with these therapies achieve durable immune response and disease control. It may be that CD8+ T cells need help from other immune cells to generate effective and long-lasting anti-tumor immunity or that CD8+ T cells alone are insufficient for complete tumor regression and cure. Melanoma contains significant numbers of B cells; however, the role of B cells in anti-melanoma immunity is controversial. In this study, B16 melanoma mouse models were used to determine the role of B cells in anti-melanoma immunity. C57BL/6 mice, B cell knockout (KO) C57BL/6 mice, anti-CD19, and anti-CXCL13 antibody-treated C57BL/6 mice were used to determine treatment efficacy and generation of tumor-specific CD8+ T cells in response to PD-L1 blockade alone or combination with TLR-7/8 activation. Whole transcriptome analysis was performed on the tumors from B cell depleted and WT mice, untreated or treated with anti-PD-L1. Both CD40-positive and CD40-negative B cells were isolated from tumors of TLR-7/8 agonist-treated wild-type mice and adoptively transferred into tumor-bearing B cell KO mice, which were treated with anti-PD-L1 and TLR-7/8 agonist. Therapeutic efficacy was determined in the presence of activated or inactivated B cells. Microarray analysis was performed on TLR-7/8-treated tumors to look for the B cell signatures. We found B cells were required to enhance the therapeutic efficacy of monotherapy with anti-PD-L1 antibody and combination therapy with anti-PD-L1 antibody plus TLR-7/8 agonist. However, B cells were not essential for anti-CTLA-4 antibody activity. Interestingly, CD40-positive but not CD40-negative B cells contributed to anti-melanoma immunity. In addition, melanoma patients' TCGA data showed that the presence of B cell chemokine CXCL13 and B cells together with CD8+ T cells in tumors were strongly associated with improved overall survival. Our transcriptome data suggest that the absence of B cells enhances immune checkpoints expression in the tumors microenvironment. These results revealed the importance of B cells in the generation of effective anti-melanoma immunity in response to PD-1-PD-L1 blockade immunotherapy. Our findings may facilitate the design of more effective anti-melanoma immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos , Melanoma Experimental , Animales , Anticuerpos/uso terapéutico , Humanos , Inmunoterapia/métodos , Ratones , Ratones Endogámicos C57BL , Receptor Toll-Like 7 , Microambiente Tumoral
9.
Facial Plast Surg Aesthet Med ; 24(3): 233-238, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35724255

RESUMEN

Background: Postoperative rhinoplasty infection can lead to serious cosmetic deformity, loss of structural integrity to the nose, and functional deficiencies. Understanding the factors contributing to postoperative infection is important. Microbial biofilms and persister cells play an important role in health care-associated infections. The objective of this study is to identify microbial biofilm and persister cells in the nasal soft tissue of patients undergoing revision rhinoplasty. Methods: Fourteen patients undergoing rhinoplasty were recruited for this study. Nasal soft tissue was removed during rhinoplasty and preserved in 2% paraformaldehyde/2.5% glutaraldehyde. High-resolution images were then obtained from these nasal soft tissue samples. Results: Three samples were positive for the presence of microbial persister cells or biofilms. All samples came from patients undergoing revision rhinoplasty. These patients had between one to six previous rhinoplasty procedures and one patient had previous injectable nasal filler. Conclusions: Biofilms and persister cells are able to form in nasal soft tissue of revision rhinoplasty patients in the absence of an implant and may contribute to increased postoperative infection risk.


Asunto(s)
Deformidades Adquiridas Nasales , Rinoplastia , Biopelículas , Humanos , Nariz/cirugía , Deformidades Adquiridas Nasales/cirugía , Complicaciones Posoperatorias/cirugía , Reoperación , Rinoplastia/métodos
10.
Genetics ; 221(1)2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35323874

RESUMEN

The nematode Caenorhabditis elegans has shed light on many aspects of eukaryotic biology, including genetics, development, cell biology, and genomics. A major factor in the success of C. elegans as a model organism has been the availability, since the late 1990s, of an essentially gap-free and well-annotated nuclear genome sequence, divided among 6 chromosomes. In this review, we discuss the structure, function, and biology of C. elegans chromosomes and then provide a general perspective on chromosome biology in other diverse nematode species. We highlight malleable chromosome features including centromeres, telomeres, and repetitive elements, as well as the remarkable process of programmed DNA elimination (historically described as chromatin diminution) that induces loss of portions of the genome in somatic cells of a handful of nematode species. An exciting future prospect is that nematode species may enable experimental approaches to study chromosome features and to test models of chromosome evolution. In the long term, fundamental insights regarding how speciation is integrated with chromosome biology may be revealed.


Asunto(s)
Caenorhabditis elegans , Nematodos , Animales , Caenorhabditis elegans/genética , Centrómero , Cromatina/genética , Cromosomas/genética , Nematodos/genética , Telómero/genética
11.
Nat Commun ; 13(1): 837, 2022 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-35149688

RESUMEN

Small RNA pathways play key and diverse regulatory roles in C. elegans, but our understanding of their conservation and contributions in other nematodes is limited. We analyzed small RNA pathways in the divergent parasitic nematode Ascaris. Ascaris has ten Argonautes with five worm-specific Argonautes (WAGOs) that associate with secondary 5'-triphosphate 22-24G-RNAs. These small RNAs target repetitive sequences or mature mRNAs and are similar to the C. elegans mutator, nuclear, and CSR-1 small RNA pathways. Even in the absence of a piRNA pathway, Ascaris CSR-1 may still function to "license" as well as fine-tune or repress gene expression. Ascaris ALG-4 and its associated 26G-RNAs target and likely repress specific mRNAs during testis meiosis. Ascaris WAGO small RNAs demonstrate target plasticity changing their targets between repeats and mRNAs during development. We provide a unique and comprehensive view of mRNA and small RNA expression throughout spermatogenesis. Overall, our study illustrates the conservation, divergence, dynamics, and flexibility of small RNA pathways in nematodes.


Asunto(s)
Ascaris/genética , Ascaris/metabolismo , ARN Interferente Pequeño/metabolismo , Animales , Proteínas Argonautas/metabolismo , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Regulación del Desarrollo de la Expresión Génica , Silenciador del Gen , Células Germinativas/metabolismo , Filogenia , ARN Mensajero/metabolismo , Espermatogénesis/genética
12.
Ann Surg Open ; 3(1): e141, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37600110

RESUMEN

Objective: We describe a structured approach to developing a standardized curriculum for surgical trainees in East, Central, and Southern Africa (ECSA). Summary Background Data: Surgical education is essential to closing the surgical access gap in ECSA. Given its importance for surgical education, the development of a standardized curriculum was deemed necessary. Methods: We utilized Kern's 6-step approach to curriculum development to design an online, modular, flipped-classroom surgical curriculum. Steps included global and targeted needs assessments, determination of goals and objectives, the establishment of educational strategies, implementation, and evaluation. Results: Global needs assessment identified the development of a standardized curriculum as an essential next step in the growth of surgical education programs in ECSA. Targeted needs assessment of stakeholders found medical knowledge challenges, regulatory requirements, language variance, content gaps, expense and availability of resources, faculty numbers, and content delivery method to be factors to inform curriculum design. Goals emerged to increase uniformity and consistency in training, create contextually relevant material, incorporate best educational practices, reduce faculty burden, and ease content delivery and updates. Educational strategies centered on developing an online, flipped-classroom, modular curriculum emphasizing textual simplicity, multimedia components, and incorporation of active learning strategies. The implementation process involved establishing thematic topics and subtopics, the content of which was authored by regional surgeon educators and edited by content experts. Evaluation was performed by recording participation, soliciting user feedback, and evaluating scores on a certification examination. Conclusions: We present the systematic design of a large-scale, context-relevant, data-driven surgical curriculum for the ECSA region.

14.
J Immunol ; 206(8): 1966-1975, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33722878

RESUMEN

Inflammation has long been associated with cancer initiation and progression; however, how inflammation causes immune suppression in the tumor microenvironment and resistance to immunotherapy is not well understood. In this study, we show that both innate proinflammatory cytokine IL-1α and immunotherapy-induced IL-1α make melanoma resistant to immunotherapy. In a mouse melanoma model, we found that tumor size was inversely correlated with response to immunotherapy. Large tumors had higher levels of IL-1α, Th2 cytokines, polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs), and regulatory T cells but lower levels of IL-12, Th1 cytokines, and activated T cells. We found that therapy with adenovirus-encoded CD40L (rAd.CD40L) increased tumor levels of IL-1α and PMN-MDSCs. Blocking the IL-1 signaling pathway significantly decreased rAd.CD40L-induced PMN-MDSCs and their associated PD-L1 expression in the tumor microenvironment and enhanced tumor-specific immunity. Similarly, blocking the IL-1 signaling pathway improved the antimelanoma activity of anti-PD-L1 Ab therapy. Our study suggests that blocking the IL-1α signaling pathway may increase the efficacy of immunotherapies against melanoma.


Asunto(s)
Resistencia a Antineoplásicos/inmunología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia/métodos , Interleucina-1alfa/inmunología , Melanoma Experimental/terapia , Animales , Línea Celular Tumoral , Citocinas/inmunología , Citocinas/metabolismo , Humanos , Inhibidores de Puntos de Control Inmunológico/inmunología , Interleucina-1alfa/metabolismo , Estimación de Kaplan-Meier , Melanoma Experimental/inmunología , Ratones Endogámicos C57BL , Células Supresoras de Origen Mieloide/inmunología , Células Supresoras de Origen Mieloide/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología
15.
Cell Metab ; 33(1): 78-93.e7, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33406405

RESUMEN

Obesity is often linked to malignancies including multiple myeloma, and the underlying mechanisms remain elusive. Here we showed that acetyl-CoA synthetase 2 (ACSS2) may be an important linker in obesity-related myeloma. ACSS2 is overexpressed in myeloma cells derived from obese patients and contributes to myeloma progression. We identified adipocyte-secreted angiotensin II as a direct cause of adiposity in increased ACSS2 expression. ACSS2 interacts with oncoprotein interferon regulatory factor 4 (IRF4), and enhances IRF4 stability and IRF4-mediated gene transcription through activation of acetylation. The importance of ACSS2 overexpression in myeloma is confirmed by the finding that an inhibitor of ACSS2 reduces myeloma growth both in vitro and in a diet-induced obese mouse model. Our findings demonstrate a key impact for obesity-induced ACSS2 on the progression of myeloma. Given the central role of ACSS2 in many tumors, this mechanism could be important to other obesity-related malignancies.


Asunto(s)
Acetato CoA Ligasa/genética , Mieloma Múltiple/genética , Obesidad/genética , Acetato CoA Ligasa/metabolismo , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Obesidad/metabolismo
16.
Elife ; 92020 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-33155980

RESUMEN

Human ascariasis is a major neglected tropical disease caused by the nematode Ascaris lumbricoides. We report a 296 megabase (Mb) reference-quality genome comprised of 17,902 protein-coding genes derived from a single, representative Ascaris worm. An additional 68 worms were collected from 60 human hosts in Kenyan villages where pig husbandry is rare. Notably, the majority of these worms (63/68) possessed mitochondrial genomes that clustered closer to the pig parasite Ascaris suum than to A. lumbricoides. Comparative phylogenomic analyses identified over 11 million nuclear-encoded SNPs but just two distinct genetic types that had recombined across the genomes analyzed. The nuclear genomes had extensive heterozygosity, and all samples existed as genetic mosaics with either A. suum-like or A. lumbricoides-like inheritance patterns supporting a highly interbred Ascaris species genetic complex. As no barriers appear to exist for anthroponotic transmission of these 'hybrid' worms, a one-health approach to control the spread of human ascariasis will be necessary.


Asunto(s)
Ascariasis/parasitología , Ascaris lumbricoides/genética , Ascaris suum/genética , Enfermedades de los Porcinos/parasitología , Animales , Ascariasis/veterinaria , Ascaris lumbricoides/patogenicidad , Ascaris suum/patogenicidad , Ciclooxigenasa 1/genética , Femenino , Genoma de los Helmintos/genética , Genoma Mitocondrial/genética , Heterocigoto , Humanos , Hibridación Genética/genética , Kenia , Masculino , Filogenia , Polimorfismo de Nucleótido Simple/genética , Proteoma/genética , Porcinos
17.
Front Microbiol ; 11: 530661, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33250861

RESUMEN

To characterize the ATLO (Assembly, Test, and Launch Operations) environment of the OSIRIS-REx spacecraft, we analyzed 17 aluminum witness foils and two blanks for bacterial, archaeal, fungal, and arthropod DNA. Under NASA's Planetary Protection guidelines, OSIRIS-REx is a Category II outbound, Category V unrestricted sample return mission. As a result, it has no bioburden restrictions. However, the mission does have strict organic contamination requirements to achieve its primary objective of returning pristine carbonaceous asteroid regolith to Earth. Its target, near-Earth asteroid (101955) Bennu, is likely to contain organic compounds that are biologically available. Therefore, it is useful to understand what organisms were present during ATLO as part of the larger contamination knowledge effort-even though it is unlikely that any of the organisms will survive the multi-year deep space journey. Even though these samples of opportunity were not collected or preserved for DNA analysis, we successfully amplified bacterial and archaeal DNA (16S rRNA gene) from 16 of the 17 witness foils containing as few as 7 ± 3 cells per sample. Fungal DNA (ITS1) was detected in 12 of the 17 witness foils. Despite observing arthropods in some of the ATLO facilities, arthropod DNA (COI gene) was not detected. We observed 1,009 bacterial and archaeal sOTUs (sub-operational taxonomic units, 100% unique) and 167 fungal sOTUs across all of our samples (25-84 sOTUs per sample). The most abundant bacterial sOTU belonged to the genus Bacillus. This sOTU was present in blanks and may represent contamination during sample handling or storage. The sample collected from inside the fairing just prior to launch contained several unique bacterial and fungal sOTUs that describe previously uncharacterized potential for contamination during the final phase of ATLO. Additionally, fungal richness (number of sOTUs) negatively correlates with the number of carbon-bearing particles detected on samples. The total number of fungal sequences positively correlates with total amino acid concentration. These results demonstrate that it is possible to use samples of opportunity to characterize the microbiology of low-biomass environments while also revealing the limitations imposed by sample collection and preservation methods not specifically designed with biology in mind.

18.
Front Immunol ; 11: 1816, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32903557

RESUMEN

Intravenous immunoglobulin G (IVIgG) is approved for primary immunodeficiency syndromes but may induce anti-cancer effects, and while this has been attributed to its anti-inflammatory properties, IgG against specific tumor targets may play a role. We evaluated IVIgG alone, and with a Heat shock protein (HSP)-90 or proteasome inhibitor, using multiple myeloma and mantle cell lymphoma (MCL) cells in vitro, and with the proteasome inhibitor bortezomib in vivo. IVIgG inhibited the growth of all cell lines tested, induced G1 cell cycle arrest, and suppressed pro-tumor cytokines including Interleukin (IL)-6, IL-8, and IL-10. Genomic and proteomic studies showed that IVIgG reduced tumor cell HSP70-1 levels by suppressing the ability of extracellular HSP70-1 to stimulate endogenous HSP70-1 promoter activity, and reduced extracellular vesicle uptake. Preparations of IVIgG were found to contain high titers of anti-HSP70-1 IgG, and recombinant HSP70-1 reduced the efficacy of IVIgG to suppress HSP70-1 levels. Combining IVIgG with the HSP90 inhibitor AUY922 produced superior cell growth inhibition and correlated with HSP70-1 suppression. Also, IVIgG with bortezomib or carfilzomib was superior to each single agent, and enhanced bortezomib's activity in bortezomib-resistant myeloma cells. Moreover, IVIgG reduced transfer of extracellular vesicles (EVs) to cells, and blocked transfer of bortezomib resistance through EVs. Finally, IVIgG with bortezomib were superior to the single agents in an in vivo myeloma model. These studies support the possibility that anti-HSP70-1 IgG contained in IVIgG can inhibit myeloma and MCL growth by interfering with a novel mechanism involving uptake of exogenous HSP70-1 which then induces its own promoter.


Asunto(s)
Proteínas HSP70 de Choque Térmico/efectos de los fármacos , Inmunoglobulinas Intravenosas/farmacología , Linfoma de Células del Manto/inmunología , Mieloma Múltiple/inmunología , Animales , Antineoplásicos/farmacología , Bortezomib/farmacología , Línea Celular Tumoral , Proteínas HSP70 de Choque Térmico/biosíntesis , Proteínas HSP90 de Choque Térmico/inmunología , Humanos , Ratones , Ratones SCID , Inhibidores de Proteasoma/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Elife ; 92020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32744503

RESUMEN

Parasitic helminths use two benzoquinones as electron carriers in the electron transport chain. In normoxia, they use ubiquinone (UQ), but in anaerobic conditions inside the host, they require rhodoquinone (RQ) and greatly increase RQ levels. We previously showed the switch from UQ to RQ synthesis is driven by a change of substrates by the polyprenyltransferase COQ-2 (Del Borrello et al., 2019; Roberts Buceta et al., 2019); however, the mechanism of substrate selection is not known. Here, we show helminths synthesize two coq-2 splice forms, coq-2a and coq-2e, and the coq-2e-specific exon is only found in species that synthesize RQ. We show that in Caenorhabditis elegans COQ-2e is required for efficient RQ synthesis and survival in cyanide. Importantly, parasites switch from COQ-2a to COQ-2e as they transit into anaerobic environments. We conclude helminths switch from UQ to RQ synthesis principally via changes in the alternative splicing of coq-2.


Asunto(s)
Transferasas Alquil y Aril/genética , Empalme Alternativo , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Ubiquinona/análogos & derivados , Transferasas Alquil y Aril/metabolismo , Animales , Caenorhabditis elegans/enzimología , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Nematodos/enzimología , Nematodos/genética , Nematodos/metabolismo , Oxidación-Reducción , Platelmintos/enzimología , Platelmintos/genética , Platelmintos/metabolismo , Ubiquinona/metabolismo
20.
Sci Rep ; 10(1): 13586, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32788636

RESUMEN

P-glycoproteins (Pgp) have been proposed as contributors to the widespread macrocyclic lactone (ML) resistance in several nematode species including a major pathogen of foals, Parascaris univalens. Using new and available RNA-seq data, ten different genomic loci encoding Pgps were identified and characterized by transcriptome-guided RT-PCRs and Sanger sequencing. Phylogenetic analysis revealed an ascarid-specific Pgp lineage, Pgp-18, as well as two paralogues of Pgp-11 and Pgp-16. Comparative gene expression analyses in P. univalens and Caenorhabditis elegans show that the intestine is the major site of expression but individual gene expression patterns were not conserved between the two nematodes. In P. univalens, PunPgp-9, PunPgp-11.1 and PunPgp-16.2 consistently exhibited the highest expression level in two independent transcriptome data sets. Using RNA-Seq, no significant upregulation of any Pgp was detected following in vitro incubation of adult P. univalens with ivermectin suggesting that drug-induced upregulation is not the mechanism of Pgp-mediated ML resistance. Expression and functional analyses of PunPgp-2 and PunPgp-9 in Saccharomyces cerevisiae provide evidence for an interaction with ketoconazole and ivermectin, but not thiabendazole. Overall, this study established reliable reference gene models with significantly improved annotation for the P. univalens Pgp repertoire and provides a foundation for a better understanding of Pgp-mediated anthelmintic resistance.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Ascaridoidea/genética , Proteínas del Helminto/genética , Caballos/parasitología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/clasificación , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Antiparasitarios/farmacología , Infecciones por Ascaridida/tratamiento farmacológico , Infecciones por Ascaridida/parasitología , Ascaridoidea/metabolismo , Ascaridoidea/fisiología , Resistencia a Medicamentos/efectos de los fármacos , Resistencia a Medicamentos/genética , Proteínas del Helminto/clasificación , Proteínas del Helminto/metabolismo , Ivermectina/farmacología , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN/métodos , Análisis de Secuencia de ARN/métodos , Análisis de Secuencia de ARN/estadística & datos numéricos , Transcriptoma
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