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1.
Cell ; 187(15): 4113-4127.e13, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38876107

RESUMEN

Vector-borne diseases are a leading cause of death worldwide and pose a substantial unmet medical need. Pathogens binding to host extracellular proteins (the "exoproteome") represents a crucial interface in the etiology of vector-borne disease. Here, we used bacterial selection to elucidate host-microbe interactions in high throughput (BASEHIT)-a technique enabling interrogation of microbial interactions with 3,324 human exoproteins-to profile the interactomes of 82 human-pathogen samples, including 30 strains of arthropod-borne pathogens and 8 strains of related non-vector-borne pathogens. The resulting atlas revealed 1,303 putative interactions, including hundreds of pairings with potential roles in pathogenesis, including cell invasion, tissue colonization, immune evasion, and host sensing. Subsequent functional investigations uncovered that Lyme disease spirochetes recognize epidermal growth factor as an environmental cue of transcriptional regulation and that conserved interactions between intracellular pathogens and thioredoxins facilitate cell invasion. In summary, this interactome atlas provides molecular-level insights into microbial pathogenesis and reveals potential host-directed targets for next-generation therapeutics.


Asunto(s)
Interacciones Huésped-Patógeno , Humanos , Animales , Enfermedad de Lyme/microbiología , Enfermedades Transmitidas por Vectores , Interacciones Microbiota-Huesped , Borrelia burgdorferi/patogenicidad , Borrelia burgdorferi/metabolismo
2.
PLoS Pathog ; 20(10): e1012652, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39441862

RESUMEN

Anophelinae mosquitoes are exposed to a variety of microbes including Plasmodium parasites that cause malaria. When infected, mosquitoes mount versatile immune responses, including the production of antimicrobial peptides. Cecropins are one of the most widely distributed families of antimicrobial peptides in insects and all previously studied Anopheles members are playing roles in adult mosquito immunity. We have identified and characterized a novel member of the Anopheles gambiae cecropin family, cecropin D (CecD), that is uniquely expressed and immune-responsive at late larval stages to promote microbial clearance through its broad-spectrum antibacterial activity during larval-pupal developmental transition. Interestingly, Cecropin D also exhibited highly potent activity against Plasmodium falciparum sporozoites, the malaria parasite stage that is transmitted from mosquitoes and infects humans and thereby holds promise as a malaria transmission-blocking agent. Finally, we have defined unequivocal cecropin-specific molecular signatures to systematically organize the diversity of the cecropin family in malaria vectors.

3.
PLoS Pathog ; 20(4): e1012145, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38598552

RESUMEN

Wolbachia, a maternally transmitted symbiotic bacterium of insects, can suppress a variety of human pathogens in mosquitoes, including malaria-causing Plasmodium in the Anopheles vector. However, the mechanistic basis of Wolbachia-mediated Plasmodium suppression in mosquitoes is not well understood. In this study, we compared the midgut and carcass transcriptomes of stably infected Anopheles stephensi with Wolbachia wAlbB to uninfected mosquitoes in order to discover Wolbachia infection-responsive immune genes that may play a role in Wolbachia-mediated anti-Plasmodium activity. We show that wAlbB infection upregulates 10 putative immune genes and downregulates 14 in midguts, while it upregulates 31 putative immune genes and downregulates 15 in carcasses at 24 h after blood-fed feeding, the time at which the Plasmodium ookinetes are traversing the midgut tissue. Only a few of these regulated immune genes were also significantly differentially expressed between Wolbachia-infected and non-infected midguts and carcasses of sugar-fed mosquitoes. Silencing of the Wolbachia infection-responsive immune genes TEP 4, TEP 15, lysozyme C2, CLIPB2, CLIPB4, PGRP-LD and two novel genes (a peritrophin-44-like gene and a macro domain-encoding gene) resulted in a significantly greater permissiveness to P. falciparum infection. These results indicate that Wolbachia infection modulates mosquito immunity and other processes that are likely to decrease Anopheles permissiveness to Plasmodium infection.


Asunto(s)
Anopheles , Malaria Falciparum , Plasmodium falciparum , Wolbachia , Animales , Anopheles/parasitología , Anopheles/microbiología , Anopheles/inmunología , Wolbachia/inmunología , Plasmodium falciparum/inmunología , Malaria Falciparum/inmunología , Malaria Falciparum/parasitología , Mosquitos Vectores/parasitología , Mosquitos Vectores/microbiología , Mosquitos Vectores/inmunología , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/inmunología , Transcriptoma , Femenino
4.
Trends Immunol ; 44(4): 256-265, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36964020

RESUMEN

Malaria is caused by Plasmodium protozoa that are transmitted by anopheline mosquitoes. Plasmodium sporozoites are released with saliva when an infected female mosquito takes a blood meal on a vertebrate host. Sporozoites deposited into the skin must enter a blood vessel to start their journey towards the liver. After migration out of the mosquito, sporozoites are associated with, or in proximity to, many components of vector saliva in the skin. Recent work has elucidated how Anopheles saliva, and components of saliva, can influence host-pathogen interactions during the early stage of Plasmodium infection in the skin. Here, we discuss how components of Anopheles saliva can modulate local host responses and affect Plasmodium infectivity. We hypothesize that therapeutic strategies targeting mosquito salivary proteins can play a role in controlling malaria and other vector-borne diseases.


Asunto(s)
Anopheles , Malaria , Humanos , Animales , Femenino , Anopheles/parasitología , Anopheles/fisiología , Saliva , Mosquitos Vectores/parasitología , Esporozoítos
5.
Proc Natl Acad Sci U S A ; 120(11): e2213701120, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36893279

RESUMEN

While it has long been known that the transmission of mosquito-borne viruses depends on the establishment of persistent and nonlethal infections in the invertebrate host, specific roles for the insects' antiviral immune pathways in modulating the pathogenesis of viral infections is the subject of speculation and debate. Here, we show that a loss-of-function mutation in the Aedes aegypti Dicer-2 (Dcr-2) gene renders the insect acutely susceptible to a disease phenotype upon infection with pathogens in multiple virus families associated with important human diseases. Additional interrogation of the disease phenotype demonstrated that the virus-induced pathology is controlled through a canonical RNA interference (RNAi) pathway, which functions as a resistance mechanism. These results suggest comparatively modest contributions of proposed tolerance mechanisms to the fitness of A. aegypti infected with these pathogens. Similarly, the production of virus-derived piwi-interacting RNAs (vpiRNAs) was not sufficient to prevent the pathology associated with viral infections in Dcr-2 null mutants, also suggesting a less critical, or potentially secondary, role for vpiRNAs in antiviral immunity. These findings have important implications for understanding the ecological and evolutionary interactions occurring between A. aegypti and the pathogens they transmit to human and animal hosts.


Asunto(s)
Aedes , Flavivirus , Fiebre Amarilla , Animales , Humanos , Interferencia de ARN , Fiebre Amarilla/genética , Flavivirus/genética , Antivirales , ARN Interferente Pequeño/genética
6.
Proc Natl Acad Sci U S A ; 120(29): e2221118120, 2023 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-37428915

RESUMEN

Proposed genetic approaches for reducing human malaria include population modification, which introduces genes into vector mosquitoes to reduce or prevent parasite transmission. We demonstrate the potential of Cas9/guide RNA (gRNA)-based gene-drive systems linked to dual antiparasite effector genes to spread rapidly through mosquito populations. Two strains have an autonomous gene-drive system coupled to dual anti-Plasmodium falciparum effector genes comprising single-chain variable fragment monoclonal antibodies targeting parasite ookinetes and sporozoites in the African malaria mosquitoes Anopheles gambiae (AgTP13) and Anopheles coluzzii (AcTP13). The gene-drive systems achieved full introduction within 3 to 6 mo after release in small cage trials. Life-table analyses revealed no fitness loads affecting AcTP13 gene-drive dynamics but AgTP13 males were less competitive than wild types. The effector molecules reduced significantly both parasite prevalence and infection intensities. These data supported transmission modeling of conceptual field releases in an island setting that shows meaningful epidemiological impacts at different sporozoite threshold levels (2.5 to 10 k) for human infection by reducing malaria incidence in optimal simulations by 50 to 90% within as few as 1 to 2 mo after a series of releases, and by ≥90% within 3 mo. Modeling outcomes for low sporozoite thresholds are sensitive to gene-drive system fitness loads, gametocytemia infection intensities during parasite challenges, and the formation of potentially drive-resistant genome target sites, extending the predicted times to achieve reduced incidence. TP13-based strains could be effective for malaria control strategies following validation of sporozoite transmission threshold numbers and testing field-derived parasite strains. These or similar strains are viable candidates for future field trials in a malaria-endemic region.


Asunto(s)
Anopheles , Malaria Falciparum , Malaria , Animales , Masculino , Humanos , Anopheles/genética , Anopheles/parasitología , Mosquitos Vectores/genética , Malaria/prevención & control , Plasmodium falciparum/genética , Esporozoítos , Malaria Falciparum/parasitología
7.
PLoS Pathog ; 19(6): e1011440, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37319296

RESUMEN

Long non-coding RNAs (lncRNAs) play critical regulatory roles in various cellular and metabolic processes in mosquitoes and all other organisms studied thus far. In particular, their involvement in essential processes such as reproduction makes them potential targets for the development of novel pest control approaches. However, their function in mosquito biology remains largely unexplored. To elucidate the role of lncRNAs in mosquitoes' reproduction and vector competence for arboviruses, we have implemented a computational and experimental pipeline to mine, screen, and characterize lncRNAs related to these two biological processes. Through analysis of publicly available Zika virus (ZIKV) infection-regulated Aedes aegypti transcriptomes, at least six lncRNAs were identified as being significantly upregulated in response to infection in various mosquito tissues. The roles of these ZIKV-regulated lncRNAs (designated Zinc1, Zinc2, Zinc3, Zinc9, Zinc10 and Zinc22), were further investigated by dsRNA-mediated silencing studies. Our results show that silencing of Zinc1, Zinc2, and Zinc22 renders mosquitoes significantly less permissive to ZIKV infection, while silencing of Zinc22 also reduces fecundity, indicating a potential role for Zinc22 in trade-offs between vector competence and reproduction. We also found that silencing of Zinc9 significantly increases fecundity but has no effect on ZIKV infection, suggesting that Zinc9 may be a negative regulator of oviposition. Our work demonstrates that some lncRNAs play host factor roles by facilitating viral infection in mosquitoes. We also show that lncRNAs can influence both mosquito reproduction and permissiveness to virus infection, two biological systems with important roles in mosquito vectorial capacity.


Asunto(s)
Aedes , ARN Largo no Codificante , Infección por el Virus Zika , Virus Zika , Animales , Femenino , Virus Zika/fisiología , Aedes/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Mosquitos Vectores/genética , Reproducción
8.
PLoS Pathog ; 19(1): e1010842, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36656895

RESUMEN

As a major insect vector of multiple arboviruses, Aedes aegypti poses a significant global health and economic burden. A number of genetic engineering tools have been exploited to understand its biology with the goal of reducing its impact. For example, current tools have focused on knocking-down RNA transcripts, inducing loss-of-function mutations, or expressing exogenous DNA. However, methods for transactivating endogenous genes have not been developed. To fill this void, here we developed a CRISPR activation (CRISPRa) system in Ae. aegypti to transactivate target gene expression. Gene expression is activated through pairing a catalytically-inactive ('dead') Cas9 (dCas9) with a highly-active tripartite activator, VP64-p65-Rta (VPR) and synthetic guide RNA (sgRNA) complementary to a user defined target-gene promoter region. As a proof of concept, we demonstrate that engineered Ae. aegypti mosquitoes harboring a binary CRISPRa system can be used to effectively overexpress two developmental genes, even-skipped (eve) and hedgehog (hh), resulting in observable morphological phenotypes. We also used this system to overexpress the positive transcriptional regulator of the Toll immune pathway known as AaRel1, which resulted in a significant suppression of dengue virus serotype 2 (DENV2) titers in the mosquito. This system provides a versatile tool for research pathways not previously possible in Ae. aegypti, such as programmed overexpression of endogenous genes, and may aid in gene characterization studies and the development of innovative vector control tools.


Asunto(s)
Aedes , Animales , Humanos , Proteínas Hedgehog/metabolismo , Mosquitos Vectores/genética , ARN/metabolismo , Activación Transcripcional , Sistemas CRISPR-Cas
9.
PLoS Biol ; 20(1): e3001515, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35025886

RESUMEN

Anopheles gambiae melanization-based refractoriness to the human malaria parasite Plasmodium falciparum has rarely been observed in either laboratory or natural conditions, in contrast to the rodent model malaria parasite Plasmodium berghei that can become completely melanized by a TEP1 complement-like system-dependent mechanism. Multiple studies have shown that the rodent parasite evades this defense by recruiting the C-type lectins CTL4 and CTLMA2, while permissiveness to the human malaria parasite was not affected by partial depletion of these factors by RNAi silencing. Using CRISPR/Cas9-based CTL4 knockout, we show that A. gambiae can mount melanization-based refractoriness to the human malaria parasite, which is independent of the TEP1 complement-like system and the major anti-Plasmodium immune pathway Imd. Our study indicates a hierarchical specificity in the control of Plasmodium melanization and proves CTL4 as an essential host factor for P. falciparum transmission and one of the most potent mosquito-encoded malaria transmission-blocking targets.


Asunto(s)
Anopheles/inmunología , Lectinas Tipo C/genética , Plasmodium berghei/fisiología , Plasmodium falciparum/fisiología , Animales , Anopheles/genética , Anopheles/parasitología , Sistemas CRISPR-Cas , Técnicas de Inactivación de Genes , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Lectinas Tipo C/metabolismo , Melaninas/genética , Melaninas/inmunología
10.
PLoS Biol ; 20(6): e3001668, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35679279

RESUMEN

The mosquito's innate immune system defends against a variety of pathogens, and the conserved siRNA pathway plays a central role in the control of viral infections. Here, we show that transgenic overexpression of Dicer2 (Dcr2) or R2d2 resulted in an accumulation of 21-nucleotide viral sequences that was accompanied by a significant suppression of dengue virus (DENV), Zika virus (ZIKV), and chikungunya virus (CHIKV) replication, thus indicating the broad-spectrum antiviral response mediated by the siRNA pathway that can be applied for the development of novel arbovirus control strategies. Interestingly, overexpression of Dcr2 or R2d2 regulated the mRNA abundance of a variety of antimicrobial immune genes, pointing to additional functions of DCR2 and R2D2 as well as cross-talk between the siRNA pathway and other immune pathways. Accordingly, transgenic overexpression of Dcr2 or R2d2 resulted in a lesser proliferation of the midgut microbiota and increased resistance to bacterial and fungal infections.


Asunto(s)
Aedes , Virus del Dengue , Dengue , Infección por el Virus Zika , Virus Zika , Animales , Animales Modificados Genéticamente , Antibacterianos/metabolismo , Antifúngicos , Virus del Dengue/genética , Humanos , ARN Bicatenario/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Virus Zika/genética
11.
BMC Genomics ; 25(1): 42, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38191283

RESUMEN

Gene-edited mosquitoes lacking a gamma-interferon-inducible lysosomal thiol reductase-like protein, namely (mosGILTnull) have lower Plasmodium infection, which is linked to impaired ovarian development and immune activation. The transcriptome of mosGILTnull Anopheles gambiae was therefore compared to wild type (WT) mosquitoes by RNA-sequencing to delineate mosGILT-dependent pathways. Compared to WT mosquitoes, mosGILTnull A. gambiae demonstrated altered expression of genes related to oogenesis, 20-hydroxyecdysone synthesis, as well as immune-related genes. Serendipitously, the zero population growth gene, zpg, an essential regulator of germ cell development was found to be one of the most downregulated genes in mosGILTnull mosquitoes. These results provide a crucial missing link between two previous studies on the role of zpg and mosGILT in ovarian development. This study further demonstrates that mosGILT has the potential to serve as a target for the biological control of mosquito vectors and to influence the Plasmodium life cycle within the vector.


Asunto(s)
Anopheles , Animales , Anopheles/genética , Diferenciación Celular , Inmunidad Innata/genética , Mosquitos Vectores/genética , Células Germinativas
12.
Crit Care Med ; 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39178163

RESUMEN

OBJECTIVE: To investigate the metabolomic profiles associated with different immune activation states in sepsis patients. DESIGN: Subgroup analysis of the PROVIDE (a Personalized Randomized trial of Validation and restoration of Immune Dysfunction in severe infections and Sepsis) prospective clinical study. SETTING: Results of the PROVIDE study showed that patients with sepsis may be classified into three states of immune activation: 1) macrophage-activation-like syndrome (MALS) characterized by hyperinflammation, sepsis-induced immunoparalysis, and 3) unclassified or intermediate patients without severe immune dysregulation. PATIENTS OR SUBJECTS: Two hundred ten patients from 14 clinical sites in Greece meeting the Sepsis-3 definitions with lung infection, acute cholangitis, or primary bacteremia. INTERVENTIONS: During our comparison, we did not perform any intervention. MEASUREMENTS AND MAIN RESULTS: Untargeted metabolomics analysis was performed on plasma samples from 210 patients (a total of 1394 products). Differential abundance analysis identified 221 significantly different metabolites across the immune states. Metabolites were enriched in pathways related to ubiquinone biosynthesis, tyrosine metabolism, and tryptophan metabolism when comparing MALS to immunoparalysis and unclassified patients. When comparing MALS to unclassified, 312 significantly different metabolites were found, and pathway analysis indicated enrichment in multiple pathways. Comparing immunoparalysis to unclassified patients revealed only two differentially regulated metabolites. CONCLUSIONS: Findings suggest distinct metabolic dysregulation patterns associated with different immune dysfunctions in sepsis: the strongest metabolic dysregulation is associated with MALS.

13.
Crit Care Med ; 52(11): e536-e544, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39418210

RESUMEN

OBJECTIVE: To investigate the metabolomic profiles associated with different immune activation states in sepsis patients. DESIGN: Subgroup analysis of the PROVIDE (a Personalized Randomized trial of Validation and restoration of Immune Dysfunction in severe infections and Sepsis) prospective clinical study. SETTING: Results of the PROVIDE study showed that patients with sepsis may be classified into three states of immune activation: 1) macrophage-activation-like syndrome (MALS) characterized by hyperinflammation, sepsis-induced immunoparalysis, and 3) unclassified or intermediate patients without severe immune dysregulation. PATIENTS OR SUBJECTS: Two hundred ten patients from 14 clinical sites in Greece meeting the Sepsis-3 definitions with lung infection, acute cholangitis, or primary bacteremia. INTERVENTIONS: During our comparison, we did not perform any intervention. MEASUREMENTS AND MAIN RESULTS: Untargeted metabolomics analysis was performed on plasma samples from 210 patients (a total of 1394 products). Differential abundance analysis identified 221 significantly different metabolites across the immune states. Metabolites were enriched in pathways related to ubiquinone biosynthesis, tyrosine metabolism, and tryptophan metabolism when comparing MALS to immunoparalysis and unclassified patients. When comparing MALS to unclassified, 312 significantly different metabolites were found, and pathway analysis indicated enrichment in multiple pathways. Comparing immunoparalysis to unclassified patients revealed only two differentially regulated metabolites. CONCLUSIONS: Findings suggest distinct metabolic dysregulation patterns associated with different immune dysfunctions in sepsis: the strongest metabolic dysregulation is associated with MALS.


Asunto(s)
Metabolómica , Sepsis , Humanos , Sepsis/inmunología , Sepsis/metabolismo , Sepsis/sangre , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , Anciano , Activación de Macrófagos , Metaboloma
14.
PLoS Biol ; 19(5): e3001182, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33979323

RESUMEN

Melanin, a black-brown pigment found throughout all kingdoms of life, has diverse biological functions including UV protection, thermoregulation, oxidant scavenging, arthropod immunity, and microbial virulence. Given melanin's broad roles in the biosphere, particularly in insect immune defenses, it is important to understand how exposure to ubiquitous environmental contaminants affects melanization. Glyphosate-the most widely used herbicide globally-inhibits melanin production, which could have wide-ranging implications in the health of many organisms, including insects. Here, we demonstrate that glyphosate has deleterious effects on insect health in 2 evolutionary distant species, Galleria mellonella (Lepidoptera: Pyralidae) and Anopheles gambiae (Diptera: Culicidae), suggesting a broad effect in insects. Glyphosate reduced survival of G. mellonella caterpillars following infection with the fungus Cryptococcus neoformans and decreased the size of melanized nodules formed in hemolymph, which normally help eliminate infection. Glyphosate also increased the burden of the malaria-causing parasite Plasmodium falciparum in A. gambiae mosquitoes, altered uninfected mosquito survival, and perturbed the microbial composition of adult mosquito midguts. Our results show that glyphosate's mechanism of melanin inhibition involves antioxidant synergy and disruption of the reaction oxidation-reduction balance. Overall, these findings suggest that glyphosate's environmental accumulation could render insects more susceptible to microbial pathogens due to melanin inhibition, immune impairment, and perturbations in microbiota composition, potentially contributing to declines in insect populations.


Asunto(s)
Anopheles/efectos de los fármacos , Glicina/análogos & derivados , Melaninas/metabolismo , Mariposas Nocturnas/efectos de los fármacos , Animales , Anopheles/inmunología , Cryptococcus neoformans/patogenicidad , Dípteros/efectos de los fármacos , Dípteros/inmunología , Glicina/metabolismo , Glicina/farmacología , Inmunidad Innata/efectos de los fármacos , Inmunidad Innata/inmunología , Infecciones/inmunología , Infecciones/metabolismo , Infecciones/fisiopatología , Insectos/efectos de los fármacos , Insectos/inmunología , Lepidópteros/efectos de los fármacos , Lepidópteros/inmunología , Mariposas Nocturnas/inmunología , Plasmodium falciparum/patogenicidad , Virulencia , Glifosato
15.
Molecules ; 29(10)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38792161

RESUMEN

Olive oil production is characterized by large amounts of waste, and yet is considerably highly valued. Olive pomace can serve as a cheap source of bioactive compounds (BACs) with important antioxidant activity. Novel technologies like Pulsed Electric Fields (PEF) and High Pressure (HP) and microwave (MW) processing are considered green alternatives for the recovery of BACs. Different microwave (150-600 W), PEF (1-5 kV/cm field strength, 100-1500 pulses/15 µs width), and HP (250-650 MPa) conditions, in various product/solvent ratios, methanol concentrations, extraction temperatures, and processing times were investigated. Results indicated that the optimal MW extraction conditions were 300 W at 50 °C for 5 min using 60% v/v methanol with a product/solvent ratio of 1:10 g/mL. Similarly, the mix of 40% v/v methanol with olive pomace, treated at 650 MPa for the time needed for pressure build-up (1 min) were considered as optimal extraction conditions in the case of HP, while for PEF the optimal conditions were 60% v/v methanol with a product/solvent ratio of 1:10 g/mL, treated at 5000 pulses, followed by 1 h extraction under stirring conditions. Therefore, these alternative extraction technologies could assist the conventional practice in minimizing waste production and simultaneously align with the requirements of the circular bioeconomy concept.


Asunto(s)
Antioxidantes , Electricidad , Microondas , Olea , Presión , Olea/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Extractos Vegetales/química , Solventes/química , Aceite de Oliva/química , Metanol/química
16.
PLoS Genet ; 16(4): e1008765, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32339167

RESUMEN

microRNAs (miRNAs) are increasingly recognized as important regulators of many biological processes in mosquitoes, vectors of numerous devastating infectious diseases. Identification of bona fide targets remains the bottleneck for functional studies of miRNAs. In this study, we used CLEAR-CLIP assays to systematically analyze miRNA-mRNA interactions in adult female Anopheles gambiae mosquitoes. Thousands of miRNA-target pairs were captured after direct ligation of the miRNA and its cognate target transcript in endogenous Argonaute-miRNA-mRNA complexes. Using two interactions detected in this manner, miR-309-SIX4 and let-7-kr-h1, we demonstrated the reliability of this experimental approach in identifying in vivo gene regulation by miRNAs. The miRNA-mRNA interaction dataset provided an invaluable opportunity to decipher targeting rules of mosquito miRNAs. Enriched motifs in the diverse targets of each miRNA indicated that the majority of mosquito miRNAs rely on seed-based canonical target recognition, while noncanonical miRNA binding sites are widespread and often contain motifs complementary to the central or 3' ends of miRNAs. The time-lapse study of miRNA-target interactomes in adult female mosquitoes revealed dynamic miRNA regulation of gene expression in response to varying nutritional sources and physiological demands. Interestingly, some miRNAs exhibited flexibility to use distinct sequences at different stages for target recognition. Furthermore, many miRNA-mRNA interactions displayed stage-specific patterns, especially for those genes involved in metabolism, suggesting that miRNAs play critical roles in precise control of gene expression to cope with enormous physiological demands associated with egg production. The global mapping of miRNA-target interactions contributes to our understanding of miRNA targeting specificity in non-model organisms. It also provides a roadmap for additional studies focused on regulatory functions of miRNAs in Anopheles gambiae.


Asunto(s)
Anopheles/genética , MicroARNs/metabolismo , ARN Mensajero/metabolismo , Animales , Anopheles/fisiología , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Femenino , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Estadios del Ciclo de Vida , MicroARNs/genética , ARN Mensajero/genética , Reproducción
17.
PLoS Pathog ; 16(4): e1008453, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32330198

RESUMEN

Malaria, caused by the protozoan parasite Plasmodium and transmitted by Anopheles mosquitoes, represents a major threat to human health. Plasmodium's infection cycle in the Anopheles vector is critical for transmission of the parasite between humans. The midgut-stage bottleneck of infection is largely imposed by the mosquito's innate immune system. microRNAs (miRNAs, small noncoding RNAs that bind to target RNAs to regulate gene expression) are also involved in regulating immunity and the anti-Plasmodium defense in mosquitoes. Here, we characterized the mosquito's miRNA responses to Plasmodium infection using an improved crosslinking and immunoprecipitation (CLIP) method, termed covalent ligation of endogenous Argonaute-bound RNAs (CLEAR)-CLIP. Three candidate miRNAs' influence on P. falciparum infection and midgut microbiota was studied through transgenically expressed miRNA sponges (miR-SPs) in midgut and fat body tissues. MiR-SPs mediated conditional depletion of aga-miR-14 or aga-miR-305, but not aga-miR-8, increased mosquito resistance to both P. falciparum and P. berghei infection, and enhanced the mosquitoes' antibacterial defenses. Transcriptome analysis revealed that depletion of aga-miR-14 or aga-miR-305 resulted in an increased expression of multiple immunity-related and anti-Plasmodium genes in mosquito midguts. The overall fitness cost of conditionally expressed miR-SPs was low, with only one of eight fitness parameters being adversely affected. Taken together, our results demonstrate that targeting mosquito miRNA by conditional expression of miR-SPs may have potential for the development of malaria control through genetically engineered mosquitoes.


Asunto(s)
Anopheles/inmunología , Malaria Falciparum/parasitología , MicroARNs/inmunología , Mosquitos Vectores/inmunología , Plasmodium berghei/fisiología , Plasmodium falciparum/fisiología , Animales , Anopheles/genética , Anopheles/parasitología , Femenino , MicroARNs/genética , Mosquitos Vectores/genética , Mosquitos Vectores/parasitología , Plasmodium berghei/genética , Plasmodium berghei/inmunología , Plasmodium falciparum/genética , Plasmodium falciparum/inmunología
18.
Transpl Infect Dis ; 24(1): e13746, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34843161

RESUMEN

INTRODUCTION: Solid-organ transplantation (SOT) is a well-known risk factor for invasive pulmonary aspergillosis (IPA). We report on the epidemiology and outcome of SOT patients with IPA in an intensive care unit (ICU) setting. METHODS: This is a secondary study based on a subset of SOT patients from a prospective observational multicenter cohort (the AspICU project) including ICU patients with at least one Aspergillus spp. positive culture. Cases were classified as proven, probable, or putative IPA, or as Aspergillus-colonized. Mortality was reported at 12 weeks. RESULTS: The study included 52 SOT patients (of which 18 lung, 17 liver, 12 kidney, and five heart transplants). Sixteen patients had proven IPA, 28 were categorized as putative IPA (of which only five reached a probable IPA diagnosis according to the European Organization for Research and Treatment of Cancer/Mycosis Study Group and Research Consortium criteria), and eight as Aspergillus-colonization. Among patients with IPA, 20 (45.5%) developed IPA during their ICU stay following transplantation whereas 24 patients (54.5%) had a medical ICU admission. Regarding medical imaging, nearly all IPA cases presented with non-specific findings as only nine demonstrated robust findings suggestive for invasive fungal disease. Overall, severity of the disease was reflected by a high prevalence of underlying conditions and acute organ derangements. Mortality among patients with IPA was 68%. Lung transplantation was associated with better survival (50%). CONCLUSION: IPA in SOT patients in the ICU develops in the presence of overall high severity of the disease. It rarely presents with suggestive medical imaging thereby hampering diagnosis. IPA in ICU patients with SOT carries a grim prognosis.


Asunto(s)
Aspergilosis Pulmonar Invasiva , Trasplante de Órganos , Aspergillus , Estudios de Cohortes , Humanos , Unidades de Cuidados Intensivos , Aspergilosis Pulmonar Invasiva/diagnóstico por imagen , Aspergilosis Pulmonar Invasiva/epidemiología , Trasplante de Órganos/efectos adversos , Estudios Retrospectivos
19.
Int J Mol Sci ; 23(14)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35887084

RESUMEN

Cysteine-rich trypsin inhibitor-like domain (TIL)-harboring proteins are broadly distributed in nature but remain understudied in vector mosquitoes. Here we have explored the biology of a TIL domain-containing protein of the arbovirus vector Aedes aegypti, cysteine-rich venom protein 379 (CRVP379). CRVP379 was previously shown to be essential for dengue virus infection in Ae. aegypti mosquitoes. Gene expression analysis showed CRVP379 to be highly expressed in pupal stages, male testes, and female ovaries. CRVP379 expression is also increased in the ovaries at 48 h post-blood feeding. We used CRISPR-Cas9 genome editing to generate two mutant lines of CRVP379 with mutations inside or outside the TIL domain. Female mosquitoes from both mutant lines showed severe defects in their reproductive capability; mutant females also showed differences in their follicular cell morphology. However, the CRVP379 line with a mutation outside the TIL domain did not affect male reproductive performance, suggesting that some CRVP379 residues may have sexually dimorphic functions. In contrast to previous reports, we did not observe a noticeable difference in dengue virus infection between the wild-type and any of the mutant lines. The importance of CRVP379 in Ae. aegypti reproductive biology makes it an interesting candidate for the development of Ae. aegypti population control methods.


Asunto(s)
Aedes , Dengue , Virosis , Animales , Cisteína/metabolismo , Femenino , Masculino , Mosquitos Vectores/genética , Reproducción/genética , Tripsina/metabolismo , Inhibidores de Tripsina/metabolismo
20.
Antimicrob Agents Chemother ; 65(10): e0127421, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34310206

RESUMEN

In vitro MICs and in vivo pharmacodynamics of ceftazidime and cefepime human-simulated regimens (HSR) against modified carbapenem inactivation method (mCIM)-positive Pseudomonas aeruginosa isolates harboring different OXA-10-like subtypes were described. The murine thigh model assessed ceftazidime (2 g every 8 h [q8h] HSR) and cefepime (2 g and 1 g q8h HSR). Phenotypes were similar despite possessing OXA-10-like subtypes with differing spectra. Ceftazidime produced ≥1-log10 killing in all isolates. Cefepime activity was dose dependent and MIC driven. This approach may be useful in assessing the implications of ß-lactamase variants.


Asunto(s)
Infecciones por Pseudomonas , Pseudomonas aeruginosa , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Ceftazidima/farmacología , Cefalosporinas/farmacología , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Fenotipo , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/genética , beta-Lactamasas/genética
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