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1.
Proc Natl Acad Sci U S A ; 120(37): e2308685120, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37669374

RESUMEN

Here, we provide mechanistic support for the involvement of the CYP9A subfamily of cytochrome P450 monooxygenases in the detoxification of host plant defense compounds and chemical insecticides in Spodoptera exigua and Spodoptera frugiperda. Our comparative genomics shows that a large cluster of CYP9A genes occurs in the two species but with significant differences in its contents, including several species-specific duplicates and substantial sequence divergence, both between orthologs and between duplicates. Bioassays of CRISPR-Cas9 knockouts of the clusters show that, collectively, the CYP9As can detoxify two furanocoumarin plant defense compounds (imperatorin and xanthotoxin) and insecticides representing three different chemotypes (pyrethroids, avermectins, and oxadiazines). However, in vitro metabolic assays of heterologously expressed products of individual genes show several differences between the species in the particular CYP9As with activities against these compounds. We also find that the clusters show tight genetic linkage with high levels of pyrethroid resistance in field strains of the two species. We propose that their divergent amplifications of the CYP9A subfamily have not only contributed to the development of the broad host ranges of these species over long evolutionary timeframes but also supplied them with diverse genetic options for evolving resistance to chemical insecticides in the very recent past.


Asunto(s)
Insecticidas , Xenobióticos , Biosíntesis de Péptidos , Metabolismo Secundario , Sistema Enzimático del Citocromo P-450
2.
Nature ; 565(7739): E8, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30568306

RESUMEN

Change history: In this Letter, owing to a production error, all the data points (except the two points for O-2 and N-2, respectively) were missing in Fig. 1b. The figure has been corrected online.

3.
Small ; : e2403371, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39032159

RESUMEN

The production and application of materials are evolving towards the low-dimensional micro-nano scale. Nevertheless, the fabrication of micron-scale alloy fibers remains a challenge. Herein, a novel Ni-Co-Cr-Fe-Mo high-entropy alloy (HEA) fiber with a cold-drawn reduction rate of 99.9995% and a strain (ɛ) of 12.19 is presented without requiring intermediate annealing. The exceptional deformation strain of 11.62 within the fiber leads to extraordinary tensile strengths of 2.8 GPa at room temperature and 3.6 GPa at 123 K. The in-depth investigation of the microstructure of fibers has revealed the cold drawing deformation mechanisms mediated by the synergistic effects of plane defects. Specifically, various geometrically necessary dislocation interfaces, such as dislocation walls and microbands, along with deformation twins and long-period 9R structures, form in response to external stress when ɛ≤2.7. As the strain increases, the saturated layered structure emerges and progressively evolves into a 3D equiaxed crystal. Moreover, the formation and evolution of the 9R structure (i.e., the migration of incoherent twin boundaries), coupled with the interaction of partial dislocations and the role of deformation twins, are crucial factors determining the fiber's plastic response. This work provides a novel approach to discovering new high-strength metallic fibers with excellent deformability through plane defects engineering.

4.
Mol Ecol ; 33(16): e17463, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38984610

RESUMEN

Here we investigate the evolutionary dynamics of five enzyme superfamilies (CYPs, GSTs, UGTs, CCEs and ABCs) involved in detoxification in Helicoverpa armigera. The reference assembly for an African isolate of the major lineages, H. a. armigera, has 373 genes in the five superfamilies. Most of its CYPs, GSTs, UGTs and CCEs and a few of its ABCs occur in blocks and most of the clustered genes are in subfamilies specifically implicated in detoxification. Most of the genes have orthologues in the reference genome for the Oceania lineage, H. a. conferta. However, clustered orthologues and subfamilies specifically implicated in detoxification show greater sequence divergence and less constraint on non-synonymous differences between the two assemblies than do other members of the five superfamilies. Two duplicated CYPs, which were found in the H. a. armigera but not H. a. conferta reference genome, were also missing in 16 Chinese populations spanning two different lineages of H. a. armigera. The enzyme produced by one of these duplicates has higher activity against esfenvalerate than a previously described chimeric CYP mutant conferring pyrethroid resistance. Various transposable elements were found in the introns of most detoxification genes, generating diverse gene structures. Extensive resequencing data for the Chinese H. a. armigera and H. a. conferta lineages also revealed complex copy number polymorphisms in 17 CCE001s in a cluster also implicated in pyrethroid metabolism, with substantial haplotype differences between all three lineages. Our results suggest that cotton bollworm has a versatile complement of detoxification genes which are evolving in diverse ways across its range.


Asunto(s)
Sistema Enzimático del Citocromo P-450 , Helicoverpa armigera , Animales , China , Sistema Enzimático del Citocromo P-450/genética , Evolución Molecular , Duplicación de Gen , Helicoverpa armigera/enzimología , Helicoverpa armigera/genética , Inactivación Metabólica/genética , Filogenia
5.
Virol J ; 21(1): 168, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080730

RESUMEN

BACKGROUND: The burden and characteristics of respiratory viral infections in children hospitalized for acute respiratory tract infections (ARTIs) during the post-COVID-19 pandemic era are unclear. We analyzed the epidemiological and clinical characteristics of pediatric patients hospitalized with common respiratory virus infections before and after relaxation of non-pharmaceutical interventions in Hangzhou, China and evaluated the diagnostic value of the six-panel respiratory pathogen detection system. METHODS: Six types of respiratory viruses were detected in respiratory samples from children with suspected ARTIs by multiplex real-time quantitative polymerase chain reaction (RT-qPCR). Changes in virus detection rates and epidemiological and clinical characteristics, obtained from electronic health records, were analyzed. Binary logistic regression was used to identify respiratory tract infections risk factors. Multiplex RT-qPCR and targeted next-generation sequencing results were compared in random samples. RESULTS: Among the 11,056 pediatric samples, 3228 tested positive for one or more of six common respiratory pathogens. RSV and PIV-3 detection rates differed significantly across age groups (both P < 0.001), and were more common in younger children. PIV-1 was more common in infants, toddlers, and preschoolers than in school-age children (P < 0.001). FluB was predominantly detected in school-age children (P < 0.001). RSV-, ADV-, and PIV-1-positivity rates were higher in 2022 than in 2023. Seasonal viral patterns differed across years. RSV (OR 9.156. 95% CI 5.905-14.195) and PIV-3 (OR 1.683, 95% CI 1.133-2.501) were risk factors for lower respiratory tract infections. RSV-positivity was associated with severe pneumonia (P = 0.044). PIV-3 (OR 0.391, 95% CI 0.170-0.899), summer season (OR 1.982, 95% CI 1.117-3.519), and younger age (OR 0.938, 95% CI 0.893-0.986) influenced pneumonia severity. Multiplex RT-qPCR showed good diagnostic performance. CONCLUSION: After changes in COVID-19 prevention and control strategies, six common respiratory viruses in children were prevalent in 2022-2023, with different seasonal epidemic characteristics and age proclivities. RSV and PIV-3 cause lower, and FluA, FluB, and ADV more typically cause upper respiratory tract infections. Infancy and summer season influence severe pneumonia risk. Multiplex RT-qPCR is valuable for accurate and timely detection of respiratory viruses in children, which facilitates management, treatment, and prevention of ARTIs.


Asunto(s)
Reacción en Cadena de la Polimerasa Multiplex , Infecciones del Sistema Respiratorio , Humanos , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/virología , Infecciones del Sistema Respiratorio/diagnóstico , Niño , Preescolar , Lactante , Femenino , Masculino , China/epidemiología , Adolescente , COVID-19/epidemiología , COVID-19/diagnóstico , COVID-19/virología , Recién Nacido , Virus/aislamiento & purificación , Virus/genética , Virus/clasificación , Virosis/epidemiología , Virosis/virología , Virosis/diagnóstico , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Hospitalización , Factores de Riesgo , Reacción en Cadena en Tiempo Real de la Polimerasa , Secuenciación de Nucleótidos de Alto Rendimiento , Estudios Epidemiológicos , Estaciones del Año
6.
Nature ; 563(7732): 546-550, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30429610

RESUMEN

Oxygen, one of the most abundant elements on Earth, often forms an undesired interstitial impurity or ceramic phase (such as an oxide particle) in metallic materials. Even when it adds strength, oxygen doping renders metals brittle1-3. Here we show that oxygen can take the form of ordered oxygen complexes, a state in between oxide particles and frequently occurring random interstitials. Unlike traditional interstitial strengthening4,5, such ordered interstitial complexes lead to unprecedented enhancement in both strength and ductility in compositionally complex solid solutions, the so-called high-entropy alloys (HEAs)6-10. The tensile strength is enhanced (by 48.5 ± 1.8 per cent) and ductility is substantially improved (by 95.2 ± 8.1 per cent) when doping a model TiZrHfNb HEA with 2.0 atomic per cent oxygen, thus breaking the long-standing strength-ductility trade-off11. The oxygen complexes are ordered nanoscale regions within the HEA characterized by (O, Zr, Ti)-rich atomic complexes whose formation is promoted by the existence of chemical short-range ordering among some of the substitutional matrix elements in the HEAs. Carbon has been reported to improve strength and ductility simultaneously in face-centred cubic HEAs12, by lowering the stacking fault energy and increasing the lattice friction stress. By contrast, the ordered interstitial complexes described here change the dislocation shear mode from planar slip to wavy slip, and promote double cross-slip and thus dislocation multiplication through the formation of Frank-Read sources (a mechanism explaining the generation of multiple dislocations) during deformation. This ordered interstitial complex-mediated strain-hardening mechanism should be particularly useful in Ti-, Zr- and Hf-containing alloys, in which interstitial elements are highly undesirable owing to their embrittlement effects, and in alloys where tuning the stacking fault energy and exploiting athermal transformations13 do not lead to property enhancement. These results provide insight into the role of interstitial solid solutions and associated ordering strengthening mechanisms in metallic materials.

7.
Retina ; 44(1): 166-174, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37695977

RESUMEN

PURPOSE: To investigate the possible correlation factors of choroidal thickness in ABCA4 -related retinopathy. METHODS: A total of 66 patients were included in the cohort. It is a retrospective, cross-sectional laboratory investigation. The patients were tested using whole-exon sequencing and ophthalmic examinations, including slit-lamp examinations, best-corrected visual acuity, spectral-domain optical coherence tomography, fundus photograph, and fundus autofluorescence. RESULTS: Besides demographic characteristics (age, onset age, duration), we selected genetic factors and ocular characteristics on spectral-domain optical coherence tomography as the candidates related to choroidal thickness. Mutation type (inframe mutation or premature termination codon), epiretinal membrane, retinal pigment epithelium- Bruch membrane integrity, and macular curvature changes were identified as related factors to choroidal thickness in ABCA4 -related retinopathy after the adjustment of Logistic LASSO regression. CONCLUSION: Mutation type, epiretinal membrane, retinal pigment epithelium-Bruch membrane integrity, and macular curvature changes are related factors to choroidal thinning. These findings could provide us a further understanding for the pathological process and clinical features of ABCA4 mutation.


Asunto(s)
Membrana Epirretinal , Enfermedades de la Retina , Humanos , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Estudios Transversales , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Enfermedades de la Retina/patología , Transportadoras de Casetes de Unión a ATP/genética
8.
PLoS Genet ; 17(7): e1009680, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34252082

RESUMEN

The evolution of insecticide resistance represents a global constraint to agricultural production. Because of the extreme genetic diversity found in insects and the large numbers of genes involved in insecticide detoxification, better tools are needed to quickly identify and validate the involvement of putative resistance genes for improved monitoring, management, and countering of field-evolved insecticide resistance. The avermectins, emamectin benzoate (EB) and abamectin are relatively new pesticides with reduced environmental risk that target a wide number of insect pests, including the beet armyworm, Spodoptera exigua, an important global pest of many crops. Unfortunately, field resistance to avermectins recently evolved in the beet armyworm, threatening the sustainable use of this class of insecticides. Here, we report a high-quality chromosome-level assembly of the beet armyworm genome and use bulked segregant analysis (BSA) to identify the locus of avermectin resistance, which mapped on 15-16 Mbp of chromosome 17. Knockout of the CYP9A186 gene that maps within this region by CRISPR/Cas9 gene editing fully restored EB susceptibility, implicating this gene in avermectin resistance. Heterologous expression and in vitro functional assays further confirm that a natural substitution (F116V) found in the substrate recognition site 1 (SRS1) of the CYP9A186 protein results in enhanced metabolism of EB and abamectin. Hence, the combined approach of coupling gene editing with BSA allows for the rapid identification of metabolic resistance genes responsible for insecticide resistance, which is critical for effective monitoring and adaptive management of insecticide resistance.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Resistencia a los Insecticidas/genética , Spodoptera/genética , Animales , Mapeo Cromosómico/métodos , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Edición Génica/métodos , Genoma/genética , Insecticidas/farmacología , Ivermectina/análogos & derivados , Ivermectina/farmacología , Larva/genética , Spodoptera/metabolismo
9.
Int J Biometeorol ; 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39373934

RESUMEN

Determining the factors that drive vegetation variation is complicated by the intricate interactions between climatic and anthropogenic influences. Neglecting the short-term time-lag and cumulative effects of climate on vegetation growth (i.e., temporal effects) exacerbates the uncertainty in attributing long-term vegetation dynamics. This study evaluated the climatic and anthropogenic influences on vegetation dynamics in China from 2000 to 2019 by analyzing normalized difference vegetation index (NDVI), temperature, precipitation, solar radiation, and ten anthropogenic indicators through linear regression, correlation, multiple linear regression (MLR), residual, and principal component analyses. Across most regions, growing season NDVI (G-NDVI) exhibited heightened sensitivity to climatic variables from earlier periods or from both earlier and current periods, signaling extensive temporal climatic effects. Constructing new time series for temperature, precipitation, and solar radiation from 2000 to 2019, based on the optimal vegetation response timing to each climatic variable, revealed significant correlations with G-NDVI across 27.9%, 26.7%, and 23.3% of the study area, respectively. Climate variability and anthropogenic activities contributed 45% and 55% to the G-NDVI increase in China, respectively. Afforestation significantly promoted vegetation greening, while agricultural development had a marginally positive influence. In contrast, urbanization negatively impacted vegetation, particularly in eastern China, where farmland conversion to constructed land has been prevalent over the past two decades. Neglecting temporal effects would significantly reduce the areas with robust MLR models linking G-NDVI to climatic variables, thereby increasing uncertainty in attributing vegetation changes. The findings highlight the necessity of integrating multiple anthropogenic factors and climatic temporal effects in evaluating vegetation dynamics and ecological restoration.

10.
Pestic Biochem Physiol ; 204: 106068, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39277415

RESUMEN

The insecticidal crystalline (Cry) and vegetative insecticidal (Vip) proteins derived from Bacillus thuringiensis (Bt) are used globally to manage insect pests, including the cotton bollworm, Helicoverpa armigera, one of the world's most damaging agricultural pests. Cry proteins bind to the ATP-binding cassette transporter C2 (ABCC2) receptor on the membrane surface of larval midgut cells, resulting in Cry toxin pores, and ultimately leading to cell swelling and/or lysis. Insect aquaporin (AQP) proteins within the membranes of larval midgut cells are proposed to allow the rapid influx of water into enterocytes following the osmotic imbalance triggered by the formation of Cry toxin pores. Here, we examined the involvement of H. armigera AQPs in Cry1Ac-induced osmotic cell swelling. We identified and characterized eight H. armigera AQPs and demonstrated that five are functional water channel proteins. Three of these (HaDrip1, HaPrip, and HaEglp1) were found to be expressed in the larval midgut. Xenopus laevis oocytes co-expressing the known Cry1Ac receptor HaABCC2 and each of the three HaAQPs displayed abnormal morphology and were lysed following exposure to Cry1Ac, suggesting a rapid influx of water was induced after Cry1Ac pore formation. In contrast, oocytes producing either HaABCC2 or HaAQP alone failed to swell or lyse after treatment with Cry1Ac, implying that both Cry1Ac pore formation and HaAQP function are needed for osmotic cell swelling. However, CRISPR/Cas9-mediated knockout of any one of the three HaAQP genes failed to cause significant changes in susceptibility to the Bt toxins Cry1Ac, Cry2Ab, or Vip3Aa. Our findings suggest that the multiple HaAQPs produced in larval midgut cells compensate for each other in allowing for the rapid influx of water in H. armigera midgut cells following Cry toxin pore formation, and that mutations affecting a single HaAQP are unlikely to confer resistance to Bt proteins.


Asunto(s)
Acuaporinas , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas , Endotoxinas , Proteínas Hemolisinas , Larva , Mariposas Nocturnas , Animales , Toxinas de Bacillus thuringiensis/toxicidad , Proteínas Hemolisinas/toxicidad , Proteínas Hemolisinas/farmacología , Proteínas Hemolisinas/metabolismo , Endotoxinas/toxicidad , Endotoxinas/farmacología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/metabolismo , Mariposas Nocturnas/genética , Larva/efectos de los fármacos , Larva/metabolismo , Acuaporinas/metabolismo , Acuaporinas/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Bacillus thuringiensis/metabolismo , Bacillus thuringiensis/genética , Xenopus laevis , Oocitos/metabolismo , Oocitos/efectos de los fármacos , Insecticidas/toxicidad , Insecticidas/farmacología , Ósmosis , Helicoverpa armigera
11.
Pestic Biochem Physiol ; 204: 106096, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39277420

RESUMEN

Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) have revolutionized pest control. However, the evolution of resistance by target pests poses a significant threat to the long-term success of Bt crops. Understanding the genetics and mechanisms underlying Bt resistance is crucial for developing resistance detection methods and management tactics. The T92C mutation in a tetraspanin gene (HaTSPAN1), resulting in the L31S substitution, is associated with dominant resistance to Cry1Ac in a major pest, Helicoverpa armigera. Previous studies using CRISPR/Cas9 technique have demonstrated that knockin of the HaTSPAN1 T92C mutation confers a 125-fold resistance to Cry1Ac in the susceptible SCD strain of H. armigera. In this study, we employed the piggyBac transposon system to create two transgenic H. armigera strains based on SCD: one expressing the wild-type HaTSPAN1 gene (SCD-TSPANwt) and another expressing the T92C mutant form of HaTSPAN1 (SCD-TSPANmt). The SCD-TSPANmt strain exhibited an 82-fold resistance to Cry1Ac compared to the recipient SCD strain, while the SCD-TSPANwt strain remained susceptible. The Cry1Ac resistance followed an autosomal dominant inheritance mode and was genetically linked with the transgene locus in the SCD-TSPANmt strain of H. armigera. Our results further confirm the causal association between the T92C mutation of HaTSPAN1 and dominant resistance to Cry1Ac in H. armigera. Additionally, they suggest that the piggyBac-mediated transformation system we used in H. armigera is promising for functional investigations of candidate Bt resistance genes from other lepidopteran pests.


Asunto(s)
Toxinas de Bacillus thuringiensis , Proteínas Bacterianas , Endotoxinas , Proteínas Hemolisinas , Resistencia a los Insecticidas , Mariposas Nocturnas , Animales , Endotoxinas/genética , Endotoxinas/farmacología , Toxinas de Bacillus thuringiensis/farmacología , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacología , Proteínas Hemolisinas/toxicidad , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/genética , Resistencia a los Insecticidas/genética , Proteínas Bacterianas/genética , Alelos , Plantas Modificadas Genéticamente/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Bacillus thuringiensis/genética , Insecticidas/farmacología , Insecticidas/toxicidad , Helicoverpa armigera
12.
Support Care Cancer ; 31(7): 417, 2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37354259

RESUMEN

PURPOSE: To explore the mental health status of patients with cancer and related influential factors and provide a scientific basis to reduce serious emotional problems, improve the quality of life of cancer survivors and adopt targeted interventions. METHODS: A total of 517 patients who attended the oncology departments of six grade-A tertiary hospitals from July 2022 to September 2022 were selected by convenience sampling. The effects of emotional support, social media, patient-centred communication, health self-efficacy and cancer beliefs on the emotional well-being of patients with cancer were analysed based on the structural equation model. RESULTS: A Spearman correlation analysis showed a significant positive correlation among the six latent variables (P<0.01). The structural equation model path analysis showed that health self-efficacy (ß=0.374, P<0.001), cancer belief (ß=0.214, P=0.003) and emotional support (ß=0.104, P=0.031) all had positive effects on emotional health. The mediating effect results showed that cancer beliefs had a mediating effect on mental health in social media use (ß=0.106, P=0.001), emotional support (ß=0.028, P=0.002) and patient-centred communication (ß=0.050, P=0.002). Further, health self-efficacy had mediating effects on mental health in emotional support (ß=0.084, P=0.001) and patient-centred communication (ß=0.098, P=0.001). CONCLUSION: By constructing structural equation models, this study found that emotional support, cancer beliefs and health self-efficacy showed a positive effect on the emotional well-being of patients with cancer. Further, it found a mediating role of health cancer beliefs on the impact of emotional support, social media use and patient-centred communication on mental health. Additionally, health self-efficacy has a mediating role regarding the effects of emotional support and patient-centred communication on mental health.


Asunto(s)
Neoplasias , Medios de Comunicación Sociales , Humanos , Salud Mental , Calidad de Vida/psicología , Emociones , Neoplasias/psicología , Apoyo Social
13.
Pestic Biochem Physiol ; 195: 105565, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37666620

RESUMEN

Insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) have been applied in sprayable formulations and expressed in transgenic crops for the control of pests in the field. When exposed to Bt proteins insect larvae display feeding cessation, yet the mechanism for this phenomenon remains unknown. In this study, we investigated the feeding behavior and underlying mechanisms of cotton bollworm (Helicoverpa armigera) larvae after exposure to the Cry1Ac protein from Bt. Three H. armigera strains were studied: the susceptible SCD strain, the C2/3-KO strain with HaABCC2 and HaABCC3 knocked out and high-level resistance to Cry1Ac (>15,000-fold), and the SCD-KI strain with a T92C point mutation in tetraspanin (HaTSPAN1) and medium-level resistance to Cry1Ac (125-fold). When determining the percentage of insects that continued feeding after various exposure times to Cry1Ac, we observed quick cessation of feeding in larvae from the susceptible SCD strain, whereas larvae from the C2/3-KO strain did not display feeding cessation. In contrast, larvae from the SCD-KI strain rapidly recovered from the initial feeding cessation. Histopathological analyses and qRT-PCR in midguts of SCD larvae after Cry1Ac exposure detected serious epithelial damage and significantly reduced expression of the neuropeptide F gene (NPF) and its potential receptor gene NPFR, which are reported to promote insect feeding. Neither epithelial damage nor altered NPF and NPFR expression appeared in midguts of C2/3-KO larvae after Cry1Ac treatment. The same treatment in SCD-KI larvae resulted in milder epithelial damage and subsequent repair, and a decrease followed by an initial increase in NPF and NPFR expression. These results demonstrate that the feeding cessation response to Cry1Ac in cotton bollworm larvae is closely associated with midgut epithelial damage and downregulation of NPF and NPFR expression. This information provides clues to the mechanism of feeding cessation in response to Bt intoxication and contributes to the mode of action of the Cry1Ac toxin in target pests.


Asunto(s)
Bacillus thuringiensis , Insecticidas , Mariposas Nocturnas , Animales , Larva , Bacillus thuringiensis/genética , Insecticidas/toxicidad , Animales Modificados Genéticamente , Gossypium , Mariposas Nocturnas/genética
14.
Pestic Biochem Physiol ; 197: 105658, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38072533

RESUMEN

Crystalline (Cry) proteins from the bacterium Bacillus thuringiensis (Bt) are widely used in transgenic crops to control important insect pests. Bt crops have many benefits compared with traditional broad-spectrum insecticides, including improved pest control with reduced negative impacts on off-target organisms and fewer environmental consequences. Transgenic corn and cotton producing Cry2Ab Bt toxin are used globally to control several major lepidopteran pests, including the cotton bollworm, Helicoverpa armigera. Resistance to the Cry2Ab toxin and to Bt crops producing Cry2Ab is associated with mutations in the midgut ATP-binding cassette transporter ABCA2 gene in several lepidopterans. Gene-editing knockout has further shown that ABCA2 plays an important functional role in Cry2Ab intoxication. However, the precise role of ABCA2 in the mode of action of Cry2Ab has yet to be reported. Here, we used two in vitro expression systems to study the roles of the H. armigera ABCA2 (HaABCA2) protein in Cry2Ab intoxication. Cry2Ab bound to cultured Sf9 insect cells producing HaABCA2, resulting in specific and dose-dependent susceptibility to Cry2Ab. In contrast, Sf9 cells expressing recombinant mutant proteins missing at least one of the extracellular loop regions 1, 3, 4, and 6 or the intracellular loop containing nucleotide-binding domain 1 lost susceptibility to Cry2Ab, indicating these regions are important for receptor function. Consistent with these results, Xenopus laevis oocytes expressing recombinant HaABCA2 showed strong ion membrane flux in the presence of Cry2Ab, suggesting that HaABCA2 is involved in promoting pore formation during Cry2Ab intoxication. Together with previously published data, our results support HaABCA2 being an important receptor of Cry2Ab where it functions to promote intoxication in H. armigera.


Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Animales , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Helicoverpa armigera , Endotoxinas/genética , Endotoxinas/farmacología , Endotoxinas/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Toxinas de Bacillus thuringiensis/metabolismo , Resistencia a los Insecticidas/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Proteínas Bacterianas/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacología , Proteínas Hemolisinas/metabolismo , Gossypium/metabolismo , Larva/genética
15.
Annu Rev Entomol ; 67: 387-406, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34995087

RESUMEN

It is increasingly clear that pest species vary widely in their propensities to develop insecticide resistance. This review uses a comparative approach to analyze the key pest management practices and ecological and biochemical or genetic characteristics of the target that contribute to this variation. We focus on six heliothine species, three of which, Helicoverpa armigera, Heliothis virescens, and Helicoverpa zea, have developed resistances to many pesticide classes. The three others, Helicoverpa punctigera, Helicoverpa assulta, and Helicoverpa gelotopoeon, also significant pests, have developed resistance to very few pesticide classes. We find that host range and movement between alternate hosts are key ecological traits that influence effective selection intensities for resistance. Operational issues are also critical; area-wide, cross-pesticide management practices that account for these ecological factors are key to reducing selection intensity. Without such management, treatment using broad-spectrum chemicals serves to multiply the effects of host plant preference, preadaptive detoxification ability, and high genetic diversity to create a pesticide treadmill for the three high-propensity species.Without rigorous ongoing management, such a treadmill could still develop for newer, more selective chemistries and insecticidal transgenic crops.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Animales , Resistencia a los Insecticidas/genética , Larva , Mariposas Nocturnas/genética
16.
Hum Mutat ; 43(12): 2279-2294, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36317469

RESUMEN

Retinitis pigmentosa (RP) is a monogenic disease characterized by irreversible degeneration of the retina. PRPF31, the second most common causative gene of autosomal dominant RP, frequently harbors copy number variations (CNVs), but the underlying mechanism is unclear. In this study, we summarized the phenotypic and genotypic characteristics of 18 RP families (F01-F18) with variants in PRPF31. The prevalence of PRPF31 variants in our cohort of Chinese RP families was 1.7% (18/1024). Seventeen different variants in PRPF31 were detected, including eight novel variants. Notably, four novel CNVs encompassing PRPF31, with a proportion of 22.2% (4/18), were validated to harbor gross deletions involving Alu/Alu-mediated rearrangements (AAMRs) in the same orientation. Among a total of 12 CNVs of PRPF31 with breakpoints mapped on nucleotide-resolution, 10 variants (83.3%) were presumably mediated by Alu elements. Furthermore, we described the correlation between the genotypes and phenotypes in PRPF31-related RP. Our findings expand the mutational spectrum of the PRPF31 gene and provide strong evidence that Alu elements of PRPF31 probably contribute to the susceptibility to genomic rearrangement in this locus.


Asunto(s)
Variaciones en el Número de Copia de ADN , Retinitis Pigmentosa , Humanos , Análisis Mutacional de ADN , Proteínas del Ojo/genética , Linaje , Retinitis Pigmentosa/genética , Mutación , Genes Dominantes
17.
PLoS Pathog ; 16(3): e1008427, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32191775

RESUMEN

Evolution of pest resistance reduces the efficacy of insecticidal proteins from the gram-positive bacterium Bacillus thuringiensis (Bt) used widely in sprays and transgenic crops. Better understanding of the genetic basis of resistance is needed to more effectively monitor, manage, and counter pest resistance to Bt toxins. Here we used CRISPR/Cas9 gene editing to clarify the genetics of Bt resistance and the associated effects on susceptibility to other microbial insecticides in one of the world's most damaging pests, the cotton bollworm (Helicoverpa armigera). We discovered that CRISPR-mediated knockouts of ATP-binding cassette (ABC) transporter genes HaABCC2 and HaABCC3 together caused >15,000-fold resistance to Bt toxin Cry1Ac, whereas knocking out either HaABCC2 or HaABCC3 alone had little or no effect. Inheritance of resistance was autosomal and recessive. Bioassays of progeny from interstrain crosses revealed that one wild type allele of either HaABCC2 or HaABCC3 is sufficient to sustain substantial susceptibility to Cry1Ac. In contrast with previous results, susceptibility to two insecticides derived from bacteria other than Bt (abamectin and spinetoram), was not affected by knocking out HaABCC2, HaABCC3, or both. The results here provide the first evidence that either HaABCC2 or HaABCC3 protein is sufficient to confer substantial susceptibility to Cry1Ac. The functional redundancy of these two proteins in toxicity of Cry1Ac to H. armigera is expected to reduce the likelihood of field-evolved resistance relative to disruption of a toxic process where mutations affecting a single protein can confer resistance.


Asunto(s)
Bacillus thuringiensis , Proteínas Bacterianas , Endotoxinas , Proteínas Hemolisinas , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Animales , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Endotoxinas/genética , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Mariposas Nocturnas , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Control Biológico de Vectores
18.
J Clin Lab Anal ; 36(7): e24505, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35622931

RESUMEN

BACKGROUND: Although early diagnosis and management are critical for prognosis of pediatric sepsis, there are no specific diagnostic biomarkers for the hyperinflammatory state and organ dysfunction, important stages of sepsis. METHODS: We enrolled 129 children with infection into three groups: non-sepsis infection (33), Sepsis 1.0 (hyperinflammatory state, 67), and Sepsis 3.0 (organ dysfunction, 29). Another 32 children with no infections were included as controls. Serum C-reactive protein (CRP), procalcitonin (PCT), interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17, tumor necrosis factor (TNF)-α, interferon (IFN)-α, and IFN-γ were assessed to diagnose the two stages, and their diagnostic capacities were evaluated using receiver operating characteristic (ROC) curves. We also examined whether combining biomarkers improved diagnostic efficiency. RESULTS: Significantly higher CRP, PCT, and IL-6 levels were detected in the Sepsis 1.0 than the non-sepsis infection group (p < 0.001). The areas under the curve (AUCs) for diagnosing Sepsis 1.0 were 0.974 (CRP), 0.913 (PCT) and 0.919 (IL-6). A combination of any two biomarkers increased diagnostic sensitivity to ≥92.54% and specificity to 100.00%. Significantly higher PCT, IL-8, and IL-10 levels were found in the Sepsis 3.0 than the Sepsis 1.0 group (p ≤ 0.01), with AUCs for diagnosing Sepsis 3.0 0.807 (PCT), 0.711 (IL-8), and 0.860 (IL-10). Combining these three biomarkers increased diagnostic sensitivity to 96.55% and specificity to 94.03%. CONCLUSION: In pediatric sepsis, combining any two of CRP, PCT, and IL-6 can accurately diagnose the hyperinflammatory state and increase diagnostic specificity. Early diagnosis of organ dysfunction requires a combination of PCT, IL-8, and IL-10.


Asunto(s)
Polipéptido alfa Relacionado con Calcitonina , Sepsis , Biomarcadores , Proteína C-Reactiva/análisis , Niño , Diagnóstico Precoz , Humanos , Interleucina-10 , Interleucina-6 , Interleucina-8 , Insuficiencia Multiorgánica , Curva ROC , Sepsis/diagnóstico , Factor de Necrosis Tumoral alfa
19.
World J Surg Oncol ; 20(1): 259, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35978426

RESUMEN

BACKGROUND: CXC chemokine receptor gene family consists of seven well-established members which are broadly involved in biological functions of various cancers. Currently, limited studies have shed light on the expression profile of CXCR family members (CXCRs), as well as their prognostic value, in head and neck squamous cells carcinoma (HNSCC). METHODS: The data for this study were retrieved from the Cancer Genome Atlas database and other publicly available databases, including gene expression, methylation profiles, clinical information, immunological features, and prognoses. The expression pattern and prognostic values of CXCRs were identified, and the potential mechanism underlying CXCRs function in HNSCC was investigated by gene set enrichment analysis (GSEA). RESULTS: CXCRs were differentially expressed in HNSCC. As shown by Kaplan-Meier analysis, high CXCR3-6 expression was significantly associated with better prognostic outcomes of HNSCC patients, including overall survival and progression-free survival. According to the results of univariate and multivariate Cox proportional risk regression analysis, it was demonstrated that upregulation of CXCR3-6 was an independent factor for better prognosis, while the two other clinical features, age and stage, were factors for worse prognosis. A significant positive correlation between CXCR3-6 and tumor-infiltrated immune cells was revealed by results from Tumor Immune Estimation Resource and CIBERSORT analysis database. The main involvement of CXCRs in immune and inflammatory responses was further confirmed by GSEA. CONCLUSIONS: Overall, this study provided a rationale for targeting CXCRs as a promising therapeutic strategy of HNSCC.


Asunto(s)
Neoplasias de Cabeza y Cuello , Receptores CXCR , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Humanos , Estimación de Kaplan-Meier , Pronóstico , Receptores CXCR/genética , Receptores CXCR/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello
20.
Pestic Biochem Physiol ; 186: 105153, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35973775

RESUMEN

The beet armyworm, Spodoptera exigua is a global agricultural pest that is polyphagous, highly dispersive, and often difficult to control due to resistance to many insecticides. Previous studies showed that a target site mutation in the S. exigua ryanodine receptor (SeRyR) corresponding to I4743M contributes approximately 20-fold resistance to chlorantraniliprole, whereas a mutation in the cytochrome P450 enzyme CYP9A186 corresponding to F116V confers 200-fold to emamectin benzoate through enhanced metabolic detoxification. Here, high frequencies of mutations were found among six China S. exigua field populations collected from 2016 to 2019 resulting in SeRyR I4743M and CYP9A186 F116V substitutions, with some populations having high levels of resistance to chlorantraniliprole and emamectin benzoate, respectively. Whereas we found a significant correlation between emamectin benzoate resistance level and the allele frequency of CYP9A186 F116V, no significant correlation was found between chlorantraniliprole resistance level and SeRyR I4743M allele frequency in the six field populations. These results suggest that CYP9A186 F116V is a major resistance mechanism for emamectin benzoate in the tested field populations, whereas it is likely that resistance mechanisms other than SeRyR I4743M are responsible for resistance to chlorantraniliprole in the six China field populations. Because of the growing resistance to these two insecticides by S. exigua in China, the use of insecticidal compounds with different modes of action and/or other integrated pest management strategies are needed to further delay the evolution of insecticide resistance and effectively manage S. exigua in China.


Asunto(s)
Insecticidas , Animales , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Larva/genética , Mutación , Canal Liberador de Calcio Receptor de Rianodina/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Spodoptera/genética , Spodoptera/metabolismo , ortoaminobenzoatos/farmacología
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