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1.
Nature ; 579(7797): 51-55, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32132691

RESUMEN

A wide range of metals exhibit anomalous electrical and thermodynamic properties when tuned to a quantum critical point (QCP), although the origins of such strange metals have posed a long-standing mystery. The frequent association of strange metals with unconventional superconductivity and antiferromagnetic QCPs1-4 has led to the belief that they are highly entangled quantum states5. By contrast, ferromagnets are regarded as an unlikely setting for strange metals, because they are weakly entangled and their QCPs are often interrupted by competing phases or first-order phase transitions6-8. Here we provide evidence that the pure ferromagnetic Kondo lattice9,10 CeRh6Ge4 becomes a strange metal at a pressure-induced QCP. Measurements of the specific heat and resistivity under pressure demonstrate that the ferromagnetic transition is continuously suppressed to zero temperature, revealing a strange-metal behaviour around the QCP. We argue that strong magnetic anisotropy has a key role in this process, injecting entanglement in the form of triplet resonating valence bonds into the ordered ferromagnet. We show that a singular transformation in the patterns of the entanglement between local moments and conduction electrons, from triplet resonating valence bonds to Kondo-entangled singlet pairs at the QCP, causes a jump in the Fermi surface volume-a key driver of strange-metallic behaviour. Our results open up a direction for research into ferromagnetic quantum criticality and establish an alternative setting for the strange-metal phenomenon. Most importantly, strange-metal behaviour at a ferromagnetic QCP suggests that quantum entanglement-not the destruction of antiferromagnetism-is the common driver of the varied behaviours of strange metals.

2.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38189540

RESUMEN

Nanopore sequencers can enrich or deplete the targeted DNA molecules in a library by reversing the voltage across individual nanopores. However, it requires substantial computational resources to achieve rapid operations in parallel at read-time sequencing. We present a deep learning framework, NanoDeep, to overcome these limitations by incorporating convolutional neural network and squeeze and excitation. We first showed that the raw squiggle derived from native DNA sequences determines the origin of microbial and human genomes. Then, we demonstrated that NanoDeep successfully classified bacterial reads from the pooled library with human sequence and showed enrichment for bacterial sequence compared with routine nanopore sequencing setting. Further, we showed that NanoDeep improves the sequencing efficiency and preserves the fidelity of bacterial genomes in the mock sample. In addition, NanoDeep performs well in the enrichment of metagenome sequences of gut samples, showing its potential applications in the enrichment of unknown microbiota. Our toolkit is available at https://github.com/lysovosyl/NanoDeep.


Asunto(s)
Aprendizaje Profundo , Secuenciación de Nanoporos , Nanoporos , Humanos , Biblioteca de Genes , Genoma Bacteriano
3.
PLoS Pathog ; 19(8): e1011578, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37556475

RESUMEN

Fungal insect pathogens have evolved diverse mechanisms to evade host immune recognition and defense responses. However, identification of fungal factors involved in host immune evasion during cuticular penetration and subsequent hemocoel colonization remains limited. Here, we report that the entomopathogenic fungus Beauveria bassiana expresses an endo-ß-1,3-glucanase (BbEng1) that functions in helping cells evade insect immune recognition/ responses. BbEng1 was specifically expressed during infection, in response to host cuticle and hemolymph, and in the presence of osmotic or oxidative stress. BbEng1 was localized to the fungal cell surface/ cell wall, where it acts to remodel the cell wall pathogen associated molecular patterns (PAMPs) that can trigger host defenses, thus facilitating fungal cell evasion of host immune defenses. BbEng1 was secreted where it could bind to fungal cells. Cell wall ß-1,3-glucan levels were unchanged in ΔBbEng1 cells derived from in vitro growth media, but was elevated in hyphal bodies, whereas glucan levels were reduced in most cell types derived from the BbEng1 overexpressing strain (BbEng1OE). The BbEng1OE strain proliferated more rapidly in the host hemocoel and displayed higher virulence as compared to the wild type parent. Overexpression of their respective Eng1 homologs or of BbEng1 in the insect fungal pathogens, Metarhizium robertsii and M. acridum also resulted in increased virulence. Our data support a mechanism by which BbEng1 helps the fungal pathogen to evade host immune surveillance by decreasing cell wall glucan PAMPs, promoting successful fungal mycosis.


Asunto(s)
Beauveria , Metarhizium , Animales , Moléculas de Patrón Molecular Asociado a Patógenos/metabolismo , Glucanos/metabolismo , Beauveria/metabolismo , Sistema Inmunológico/metabolismo , Pared Celular/metabolismo , Insectos/microbiología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
4.
BMC Biol ; 22(1): 81, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609978

RESUMEN

BACKGROUND: Response to oxidative stress is universal in almost all organisms and the mitochondrial membrane protein, BbOhmm, negatively affects oxidative stress responses and virulence in the insect fungal pathogen, Beauveria bassiana. Nothing further, however, is known concerning how BbOhmm and this phenomenon is regulated. RESULTS: Three oxidative stress response regulating Zn2Cys6 transcription factors (BbOsrR1, 2, and 3) were identified and verified via chromatin immunoprecipitation (ChIP)-qPCR analysis as binding to the BbOhmm promoter region, with BbOsrR2 showing the strongest binding. Targeted gene knockout of BbOsrR1 or BbOsrR3 led to decreased BbOhmm expression and consequently increased tolerances to free radical generating compounds (H2O2 and menadione), whereas the ΔBbOsrR2 strain showed increased BbOhmm expression with concomitant decreased tolerances to these compounds. RNA and ChIP sequencing analysis revealed that BbOsrR1 directly regulated a wide range of antioxidation and transcription-associated genes, negatively affecting the expression of the BbClp1 cyclin and BbOsrR2. BbClp1 was shown to localize to the cell nucleus and negatively mediate oxidative stress responses. BbOsrR2 and BbOsrR3 were shown to feed into the Fus3-MAPK pathway in addition to regulating antioxidation and detoxification genes. Binding motifs for the three transcription factors were found to partially overlap in the promoter region of BbOhmm and other target genes. Whereas BbOsrR1 appeared to function independently, co-immunoprecipitation revealed complex formation between BbClp1, BbOsrR2, and BbOsrR3, with BbClp1 partially regulating BbOsrR2 phosphorylation. CONCLUSIONS: These findings reveal a regulatory network mediated by BbOsrR1 and the formation of a BbClp1-BbOsrR2-BbOsrR3 complex that orchestrates fungal oxidative stress responses.


Asunto(s)
Ciclinas , Factores de Transcripción , Factores de Transcripción/genética , Peróxido de Hidrógeno , Ciclo Celular , Estrés Oxidativo , Antioxidantes
5.
Insect Mol Biol ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38478920

RESUMEN

Odorant-binding proteins (OBPs) initiate insect olfactory perception and mediate specific binding and selection of odorants via uncertain binding mechanisms. We characterized the binding characteristics of four OBPs from the striped flea beetle Phyllotreta striolata (SFB), a major cruciferous crop pest. Tissue expression analysis revealed that the two ABPII OBPs (PstrOBP12 and PstrOBP19) were highly expressed mainly in the antenna, whereas the two minus-C OBPs (PstrOBP13 and PstrOBP16) showed a broad expression pattern. Competitive binding assays of cruciferous plant volatiles showed that PstrOBP12, PstrOBP16 and PstrOBP19 had very strong binding capacities for only two phthalate esters (Ki < 20 µM), and PstrOBP13 specifically bound to four aromatic volatiles (Ki < 11 µM). Fluorescence quenching assays displayed that two phthalate esters bound to three PstrOBPs via different quenching mechanisms. PstrOBP12/PstrOBP16-diisobutyl phthalate and PstrOBP19-bis(6-methylheptyl) phthalate followed static quenching, while PstrOBP12/PstrOBP16-bis(6-methylheptyl) phthalate and PstrOBP19-diisobutyl phthalate followed dynamic quenching. Homology modelling and molecular docking displayed that PstrOBP12-diisobutyl phthalate was driven by H-bonding and van der Waals interactions, while PstrOBP16-diisobutyl phthalate and PstrOBP19-bis(6-methylheptyl) phthalate followed hydrophobic interactions. Finally, behavioural activity analysis demonstrated that phthalate esters exhibited different behavioural activities of SFB at different doses, with low doses attracting and high doses repelling. Overall, we thus revealed the different binding properties of the three PstrOBPs to two phthalate esters, which was beneficial in shedding light on the ligand-binding mechanisms of OBPs.

6.
Br J Clin Pharmacol ; 90(1): 247-263, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37574850

RESUMEN

AIMS: Abiraterone acetate, a prodrug of abiraterone (ABI), provides an efficient therapeutic option for metastatic castration-resistant prostate cancer patients. ABI undergoes extensive metabolism in vivo and is transformed into active metabolites Δ4 -abiraterone and 3-keto-5α-abiraterone as well as inactive metabolites abiraterone sulfate and abiraterone N-oxide sulfate. We aimed to examine the effect of polymorphisms in SLCO2B1, CYP3A4 and UGT1A4 on the pharmacokinetics of ABI and its metabolites. METHODS: In this study, 81 healthy Chinese subjects were enrolled and divided into 2 groups for fasted (n = 45) and fed (n = 36) studies. Plasma samples were collected after administering a 250 mg abiraterone acetate tablet followed by liquid chromatography-tandem mass spectrometry analysis. Genotyping was performed on a MassARRAY system. The association between SLCO2B1, CYP3A4, UGT1A4 genotype and pharmacokinetic parameters of ABI and its metabolites was assessed. RESULTS: Food effect study demonstrated high fat meal remarkedly increased systemic exposure of ABI and its metabolites. The geometric mean ratio and 90% confidence interval of area under the plasma concentration-time curve from time 0 to the time of the last quantifiable concentration (AUC0-t ) and maximum plasma concentration (Cmax ) of ABI in fed state vs. fasted state were 351.64% (286.86%-431.04%) and 478.45% (390.01%-586.94%), respectively, while the corresponding results were ranging from 145.11% to 269.42% and 150.10% to 478.45% for AUC0-t and Cmax of ABI metabolites in fed state vs. fasted state, respectively. The SLCO2B1 rs1077858 had a significant influence on AUC0-t and Cmax , while 7 other SLCO2B1 variants prolonged half-life of ABI under both fasted and fed conditions. As for ABI metabolites, the systemic exposure of Δ4 -abiraterone, abiraterone sulfate and abiraterone N-oxide sulfate as well as the elimination of 3-keto-5α-abiraterone were significantly affected by SLCO2B1 polymorphisms. Polymorphisms in CYP3A4 and UGT1A4 did not significantly affect pharmacokinetics of ABI and its metabolites. CONCLUSION: Polymorphisms in SLCO2B1 were significantly related to the pharmacokinetic variability of ABI and its metabolites under both fasted and fed conditions.


Asunto(s)
Androstenos , Citocromo P-450 CYP3A , Transportadores de Anión Orgánico , Farmacocinética , Androstenos/metabolismo , Androstenos/farmacocinética , Humanos , Transportadores de Anión Orgánico/genética , Citocromo P-450 CYP3A/genética , Glucuronosiltransferasa/genética , Neoplasias de la Próstata , Polimorfismo de Nucleótido Simple , Pueblos del Este de Asia , Masculino , Voluntarios , Adulto , Ayuno , Alimentos
7.
Oecologia ; 205(1): 107-119, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38698244

RESUMEN

Community weighted mean trait, i.e., functional composition, has been extensively used for upscaling of individual traits to the community functional attributes and ecosystem functioning in recent years. Yet, the importance of intraspecific trait variation relative to species turnover in determining changes in CWM still remains unclear, especially under nutrient enrichment scenarios. In this study, we conducted a global data synthesis analysis and three nutrient addition experiments in two sites of alpine grassland to reveal the extent to which species turnover and ITV contribute to shift in CWM in response to nutrient enrichment. The results consistently show that the importance of ITV relative to species turnover in regulating CWM in response to nutrient enrichment strongly depends on trait attributes rather than on environmental factors (fertilization type, climatic factors, soil properties, and light transmittance). For whole plant traits (height) and leaf morphological traits, species turnover is generally more important than ITV in determining CWM following most treatments of nutrient addition. However, for leaf nutrient traits, ITV outweighed species turnover in determining shifts in CWM in response to almost all treatments of nutrient addition, regardless of types and gradients of the nutrient addition. Thus, our study not only provides robust evidence for trait-dependent importance of ITV in mediating community functional composition, but also highlights the need to consider the nature of functional traits in linking ITV to community assembly and ecosystem functioning under global nutrient enrichment scenarios.


Asunto(s)
Ecosistema , Nutrientes , Suelo , Hojas de la Planta , Pradera
8.
Arch Insect Biochem Physiol ; 115(2): e22088, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38349673

RESUMEN

Geranylgeranyl diphosphate synthase (GGPPS) as the short-chain prenyltransferases for catalyzing the formation of the acyclic precursor (E)-GGPP has been extensively investigated in mammals, plants, and microbes, but its functional plasticity is poorly understood in insect species. Here, a single GGPPS in leaf beetle Monolepta hieroglyphica, MhieGGPPS, was functionally investigated. Phylogenetic analysis showed that MhieGGPPS was clustered in one clade with homologs and had six conserved motifs. Molecular docking results indicated that binding sites of dimethylallyl diphosphate (DMAPP), (E)-geranyl pyrophosphate (GPP), and (E)-farnesyl pyrophosphate (FPP) were in the chain-length determination region of MhieGGPPS, respectively. In vitro, recombiant MhieGGPPS could catalyze the formation of (E)-geranylgeraniol against different combinations of substrates including isopentenyl pyrophosphate (IPP)/DMAPP, IPP/(E)-GPP, and IPP/(E)-FPP, suggesting that MhieGGPPS could not only use (E)-FPP but also (E)-GPP and DMAPP as the allylic cosubstrates. In kinetic analysis, the (E)-FPP was most tightly bound to MhieGGPPS than that of others. It was proposed that MhieGGPPS as a multifunctional enzyme is differentiated from the other GGPPSs in the animals and plants, which only accepted (E)-FPP as the allylic cosubstrate. These findings provide valuable insights into understanding the functional plasticity of GGPPS in M. hieroglyphica and the novel biosynthesis mechanism in the isoprenoid pathway.


Asunto(s)
Escarabajos , Hemiterpenos , Compuestos Organofosforados , Fosfatos de Poliisoprenilo , Sesquiterpenos , Animales , Farnesiltransferasa , Cinética , Simulación del Acoplamiento Molecular , Filogenia , Mamíferos
9.
Eur J Pediatr ; 183(7): 3001-3011, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38634891

RESUMEN

Mycoplasma pneumoniae (MP) is an important cause of community-acquired pneumonia in children and young adolescents. Despite macrolide antibiotics effectiveness as a first-line therapy, persistence of fever and/or clinical deterioration sometimes may complicate treatment and may even lead to severe systemic disease. To date, there is no consensus on alternative treatment options, optimal dosage, and duration for treating severe, progressive, and systemic MP pneumonia after macrolide treatment failure. Macrolide-resistant MP pneumonia and refractory MP pneumonia are the two major complex conditions that are clinically encountered. Currently, the vast majority of MP isolates are resistant to macrolides in East Asia, especially China, whereas in Europe and North America, whereas in Europe and North America prevalence is substantially lower than in Asia, varying across countries. The severity of pneumonia and extrapulmonary presentations may reflect the intensity of the host's immune reaction or the dissemination of bacterial infection. Children infected with macrolide-resistant MP strains who receive macrolide treatment experience persistent fever with extended antibiotic therapy and minimal decrease in MP-DNA load. Alternative second-line agents such as tetracyclines (doxycycline or minocycline) and fluoroquinolones (ciprofloxacin or levofloxacin) may lead to clinical improvement after macrolide treatment failure in children. Refractory MP pneumonia reflects a deterioration of clinical and radiological findings due to excessive immune response against the infection. Immunomodulators such as corticosteroids and intravenous immunoglobulin (IVIG) have shown promising results in treatment of refractory MP pneumonia, particularly when combined with appropriate antimicrobials. Corticosteroid-resistant hyperinflammatory MP pneumonia represents a persistent or recrudescent fever despite corticosteroid therapy with intravenous methylprednisolone at standard dosage. CONCLUSION:  This report summarizes the clinical significance of macrolide-resistant and refractory MP pneumonia and discusses the efficacy and safety of alternative drugs, with a stepwise approach to the management of MP pneumonia recommended from the viewpoint of clinical practice. WHAT IS KNOWN: • Although MP pneumonia is usually a benign self-limited infection with response macrolides as first line therapy, severe life-threatening cases may develop if additional treatment strategies are not effectively implemented. • Macrolide-resistant and refractory MP pneumonia are two conditions that may complicate the clinical course of MP pneumonia, increasing the risk for exacerbation and even death. WHAT IS NEW: • This report summarizes the clinical relevance of macrolide-resistant and refractory MP pneumonia and discusses the efficacy and safety of alternative drug therapies. • A practical stepwise approach to the management of MP pneumonia is developed based on a comprehensive analysis of existing evidence and expert opinion.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Macrólidos , Mycoplasma pneumoniae , Neumonía por Mycoplasma , Humanos , Neumonía por Mycoplasma/tratamiento farmacológico , Neumonía por Mycoplasma/diagnóstico , Antibacterianos/uso terapéutico , Niño , Macrólidos/uso terapéutico , Mycoplasma pneumoniae/aislamiento & purificación , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/microbiología , Adolescente
10.
BMC Public Health ; 24(1): 604, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38403578

RESUMEN

BACKGROUND: Sedentary behavior may influence the respiratory health, but the joint effects of sedentary behavior and physical activity on pulmonary function remains poorly elucidated. We aimed to estimate the association between sedentary behavior and physical activity with pulmonary function. METHODS: A total of 12,343 participants aged 12-79 years were analyzed from the U.S. NHANES 2007-2012. Participants were categorized into 16 groups according to the cross-tabulation of sedentary behavior time (0-4.0, 4.1-8.0, 8.1-12.0, and > 12.0 h/day) and moderate or vigorous physical activity (MVPA) (0, 1-149, 150-299, and ≥ 300 min/week). Generalized linear models were used to test the association of sedentary behavior and MVPA with pulmonary function. RESULTS: Participants with sedentary behavior > 4.0 h/day were negatively related to FEV1 (forced expiratory volume in 1 s) (ß ranging from -0.015 to -0.009, p < 0.05). Compared with the reference group (0 min of MVPA and > 12.0 h/day of sedentary behavior), the negative association of sedentary behavior ≤ 8.0 h/day with FEV1 may be reduced through appropriate MVPA (ß ranging from 0.019 to 0.030, p < 0.05). For sedentary behavior > 8.0 h/day, even MVPA ≥ 300 min/week may not decrease the negative relationships. Similar results were also observed in FVC (forced vital capacity) (ß ranging from 0.018 to 0.030, p < 0.05). In participants aged ≥ 45 years, the associations were more notable. CONCLUSION: This study indicated the sedentary behavior ≤ 4.0 h/day was a relatively healthy lifestyle for pulmonary function. Only below 8.0 h/day of sedentary behavior, the negative association with pulmonary function may be reduced through appropriate MVPA.


Asunto(s)
Ejercicio Físico , Conducta Sedentaria , Humanos , Encuestas Nutricionales , Pulmón , Estilo de Vida Saludable , Acelerometría
11.
J Invertebr Pathol ; 204: 108083, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38458350

RESUMEN

The abilities to withstand oxidation and assimilate fatty acids are critical for successful infection by many pathogenic fungi. Here, we characterized a Zn(II)2Cys6 transcription factor Bbotf1 in the insect pathogenic fungus Beauveria bassiana, which links oxidative response and fatty acid assimilation via regulating peroxisome proliferation. The null mutant ΔBbotf1 showed impaired resistance to oxidants, accompanied by decreased activities of antioxidant enzymes including CATs, PODs and SODs, and down-regulated expression of many antioxidation-associated genes under oxidative stress condition. Meanwhile, Bbotf1 acts as an activator to regulate fatty acid assimilation, lipid and iron homeostasis as well as peroxisome proliferation and localization, and the expressions of some critical genes related to glyoxylate cycle and peroxins were down-regulated in ΔBbotf1 in presence of oleic acid. In addition, ΔBbotf1 was more sensitive to osmotic stressors, CFW, SDS and LDS. Insect bioassays revealed that insignificant changes in virulence were seen between the null mutant and parent strain when conidia produced on CZP plates were used for topical application. However, propagules recovered from cadavers killed by ΔBbotf1 exhibited impaired virulence as compared with counterparts of the parent strain. These data offer a novel insight into fine-tuned aspects of Bbotf1 concerning multi-stress responses, lipid catabolism and infection cycles.


Asunto(s)
Beauveria , Ácidos Grasos , Peroxisomas , Factores de Transcripción , Beauveria/genética , Beauveria/patogenicidad , Animales , Peroxisomas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ácidos Grasos/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Antioxidantes/metabolismo , Virulencia , Estrés Oxidativo
12.
Pestic Biochem Physiol ; 200: 105832, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38582595

RESUMEN

Moth insects rely on sex pheromones for long distance attraction and searching for sex partners. The biosynthesis of moth sex pheromones involves the catalytic action of multiple enzymes, with desaturases playing a crucial role in the process of carbon chain desaturation. However, the specific desaturases involved in sex pheromone biosynthesis in fall armyworm (FAW), Spodoptera frugiperda, have not been clarified. In this study, a Δ11 desaturase (SfruDES1) gene in FAW was knocked out using the CRISPR/Cas9 genome editing system. A homozygous mutant of SfruDES1 was obtained through genetic crosses. The gas chromatography-mass spectrometry (GC-MS) analysis results showed that the three main sex pheromone components (Z7-12:Ac, Z9-14:Ac, and Z11-16:Ac) and the three minor components (Z9-14:Ald, E11-14:Ac and Z11-14:Ac) of FAW were not detected in homozygous mutant females compared to the wild type. Furthermore, behavioral assay demonstrated that the loss of SfruDES1 resulted in a significant reduction in the attractiveness of females to males, along with disruptions in mating behavior and oviposition. Additionally, in a heterologous expression system, recombinant SfruDES1 could introduce a cis double bond at the Δ11 position in palmitic acid, which resulted in the changes in components of the synthesized products. These findings suggest desaturase plays a key role in the biosynthesis of sex pheromones, and knockout of the SfruDES1 disrupts sex pheromone biosynthesis and mating behavior in FAW. The SfruDES1 could serve as tool to develop a control method for S. frugiperda.


Asunto(s)
Mariposas Nocturnas , Atractivos Sexuales , Animales , Femenino , Masculino , Spodoptera/genética , Spodoptera/metabolismo , Atractivos Sexuales/metabolismo , Oviposición , Mariposas Nocturnas/genética , Ácido Graso Desaturasas/genética , Ácido Graso Desaturasas/química , Ácido Graso Desaturasas/metabolismo
13.
BMC Biol ; 21(1): 166, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37542270

RESUMEN

BACKGROUND: The extracellular space between the cell wall and plasma membrane is a battlefield in plant-pathogen interactions. Within this space, the pathogen employs its secretome to attack the host in a variety of ways, including immunity manipulation. However, the role of the plant secretome is rarely studied for its role in disease resistance. RESULTS: Here, we examined the secretome of Verticillium wilt-resistant Gossypium hirsutum cultivar Zhongzhimian No.2 (ZZM2, encoding 95,327 predicted coding sequences) to determine its role in disease resistance against the wilt causal agent, Verticillium dahliae. Bioinformatics-driven analyses showed that the ZZM2 genome encodes 2085 secreted proteins and that these display disequilibrium in their distribution among the chromosomes. The cotton secretome displayed differences in the abundance of certain amino acid residues as compared to the remaining encoded proteins due to the localization of these putative proteins in the extracellular space. The secretome analysis revealed conservation for an allotetraploid genome, which nevertheless exhibited variation among orthologs and comparable unique genes between the two sub-genomes. Secretome annotation strongly suggested its involvement in extracellular stress responses (hydrolase activity, oxidoreductase activity, and extracellular region, etc.), thus contributing to resistance against the V. dahliae infection. Furthermore, the defense response genes (immunity marker NbHIN1, salicylic acid marker NbPR1, and jasmonic acid marker NbLOX4) were activated to varying degrees when Nicotina benthamiana leaves were agro-infiltrated with 28 randomly selected members, suggesting that the secretome plays an important role in the immunity response. Finally, gene silencing assays of 11 members from 13 selected candidates in ZZM2 displayed higher susceptibility to V. dahliae, suggesting that the secretome members confer the Verticillium wilt resistance in cotton. CONCLUSIONS: Our data demonstrate that the cotton secretome plays an important role in Verticillium wilt resistance, facilitating the development of the resistance gene markers and increasing the understanding of the mechanisms regulating disease resistance.


Asunto(s)
Ascomicetos , Verticillium , Gossypium/genética , Resistencia a la Enfermedad/genética , Secretoma , Verticillium/metabolismo , Enfermedades de las Plantas/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
Acta Biotheor ; 72(2): 6, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38819710

RESUMEN

The Y chromosome in the XY sex-determination system is often shorter than its X counterpart, a condition attributed to degeneration after Y recombination ceases. Contrary to the traditional view of continuous, gradual degeneration, our study reveals stabilization within large mating populations. In these populations, we demonstrate that both mutant and active alleles on the Y chromosome can reach equilibrium through a mutation-selection balance. However, the emergence of a new species, particularly through the founder effect, can disrupt this equilibrium. Specifically, if the male founders of a new species carry only a mutant allele for a particular Y-linked gene, this allele becomes fixed, leading to the loss of the corresponding active gene on the Y chromosome. Our findings suggest that the rate of Y-chromosome degeneration may be linked to the frequency of speciation events associated with single-male founder events.


Asunto(s)
Efecto Fundador , Cromosoma Y , Masculino , Cromosoma Y/genética , Animales , Alelos , Especiación Genética , Mutación , Femenino , Humanos , Modelos Genéticos
15.
Mol Plant Microbe Interact ; 36(1): 68-72, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36463398

RESUMEN

Verticillium wilt, caused by the fungal pathogen Verticillium dahliae, is the major cause of disease-related yield losses in cotton (Gossypium hirsutum). Despite these losses, the major cultivars of G. hirsutum remain highly susceptible to Verticillium wilt. The lack of understanding on the genetic basis for Verticillium wilt resistance may further hinder progress in deploying elite cultivars with proven resistance, such as the wilt resistant G. hirsutum cultivar Zhongzhimian No. 2. To help remedy this knowledge gap, we sequenced the whole genome of Zhongzhimian No. 2 and assembled it from a combination of PacBio long reads, Illumina short reads, and high-throughput chromosome conformation capture technologies. The final assembly of the genome was 2.33 Gb, encoding 95,327 predicted coding sequences. The GC content was 34.39% with 99.2% of the bases anchored to 26 pseudo-chromosomes that ranged from 53.8 to 127.7 Mb. This resource will help gain a detailed understanding of the genomic features governing high yield and Verticillium wilt resistance in this cultivar. Comparative genomics will be particularly helpful, since there are several published genomes of other Gossypium species. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Asunto(s)
Gossypium , Verticillium , Gossypium/microbiología , Verticillium/genética , Genes de Plantas , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/microbiología , Regulación de la Expresión Génica de las Plantas
16.
BMC Genomics ; 24(1): 46, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36707768

RESUMEN

Terpenoids are important compounds associated with the pest and herbivore resistance mechanisms of plants; consequently, it is essential to identify and explore terpene synthase (TPS) genes in maize. In the present study, we identified 31 TPS genes based on a pan-genome of 26 high-quality maize genomes containing 20 core genes (present in all 26 lines), seven dispensable genes (present in 2 to 23 lines), three near-core genes (present in 24 to 25 lines), and one private gene (present in only 1 line). Evaluation of ka/ks values of TPS in 26 varieties revealed that TPS25 was subjected to positive selection in some varieties. Six ZmTPS had ka/ks values less than 1, indicating that they were subjected to purifying selection. In 26 genomes, significant differences were observed in ZmTPS25 expression between genes affected by structural variation (SV) and those not affected by SV. In some varieties, SV altered the conserved structural domains resulting in a considerable number of atypical genes. The analysis of RNA-seq data of maize Ostrinia furnacalis feeding revealed 10 differentially expressed ZmTPS, 9 of which were core genes. However, many atypical genes for these responsive genes were identified in several genomes. These findings provide a novel resource for functional studies of ZmTPS.


Asunto(s)
Transferasas Alquil y Aril , Zea mays , Zea mays/genética , Zea mays/metabolismo , Terpenos/metabolismo , Transferasas Alquil y Aril/genética , Plantas/metabolismo
17.
BMC Genomics ; 24(1): 332, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37322453

RESUMEN

The rich genetic diversity in Citrullus lanatus and the other six species in the Citrullus genus provides important sources in watermelon breeding. Here, we present the Citrullus genus pan-genome based on the 400 Citrullus genus resequencing data, showing that 477 Mb contigs and 6249 protein-coding genes were absent in the Citrullus lanatus reference genome. In the Citrullus genus pan-genome, there are a total of 8795 (30.5%) genes that exhibit presence/absence variations (PAVs). Presence/absence variation (PAV) analysis showed that a lot of gene PAV were selected during the domestication and improvement, such as 53 favorable genes and 40 unfavorable genes were identified during the C. mucosospermus to C. lanatus landrace domestication. We also identified 661 resistance gene analogs (RGAs) in the Citrullus genus pan-genome, which contains 90 RGAs (89 variable and 1 core gene) located on the pangenome additional contigs. By gene PAV-based GWAS, 8 gene presence/absence variations were found associated with flesh color. Finally, based on the results of gene PAV selection analysis between watermelon populations with different fruit colors, we identified four non-reference candidate genes associated with carotenoid accumulation, which had a significantly higher frequency in the white flesh. These results will provide an important source for watermelon breeding.


Asunto(s)
Citrullus , Citrullus/genética , Domesticación , Fitomejoramiento , Genoma de Planta , Análisis de Secuencia de ADN
18.
Apoptosis ; 28(1-2): 39-54, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36369365

RESUMEN

Bronchopulmonary dysplasia (BPD) in neonates is the most common pulmonary disease that causes neonatal mortality, has complex pathogenesis, and lacks effective treatment. It is associated with chronic obstructive pulmonary disease, pulmonary hypertension, and right ventricular hypertrophy. The occurrence and development of BPD involve various factors, of which premature birth is the most crucial reason for BPD. Under the premise of abnormal lung structure and functional product, newborns are susceptible to damage to oxides, free radicals, hypoxia, infections and so on. The most influential is oxidative stress, which induces cell death in different ways when the oxidative stress balance in the body is disrupted. Increasing evidence has shown that programmed cell death (PCD), including apoptosis, necrosis, autophagy, and ferroptosis, plays a significant role in the molecular and biological mechanisms of BPD and the further development of the disease. Understanding the mode of PCD and its signaling pathways can provide new therapeutic approaches and targets for the clinical treatment of BPD. This review elucidates the mechanism of BPD, focusing on the multiple types of PCD in BPD and their molecular mechanisms, which are mainly based on experimental results obtained in rodents.


Asunto(s)
Displasia Broncopulmonar , Hipertensión Pulmonar , Humanos , Embarazo , Femenino , Recién Nacido , Displasia Broncopulmonar/epidemiología , Displasia Broncopulmonar/patología , Apoptosis , Pulmón/metabolismo , Estrés Oxidativo
19.
Plant Cell Environ ; 46(10): 3072-3089, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36207806

RESUMEN

Insect herbivory challenges plant survival, and coordination of the interactions between growth, herbivore resistance/tolerance is a key problem faced by plants. Based on field experiments into resistance to the Asian corn borer (ACB, Ostrinia furnacalis), we selected 10 inbred maize lines, of which five were resistant and five were susceptible to ACB. We conducted ACB larval bioassays, analysed defensive chemicals, phytohormones, and relative gene expression using RNA-seq and qPCR as well as agronomic traits, and found resistant lines had weaker inducibility, but were more resistant after ACB attack than susceptible lines. Resistance was related to high levels of major benzoxazinoids, but was not related to induced levels of JA or JA-Ile. Following combination analyses of transcriptome, metabolome and larval performance data, we discovered three benzoxazinoids biosynthesis-related transcription factors, NAC60, WRKY1 and WRKY46. Protoplast transformation analysis suggested that these may regulate maize defence-growth trade-offs by increasing levels of benzoxazinoids, JA and SA but decreasing IAA. Moreover, the resistance/tolerance-growth trade-offs were not observed in the 10 lines, and genotype-specific metabolic and genetic features probably eliminated the trade-offs. This study highlights the possibility of breeding maize varieties simultaneously with improved defences and higher yield under complex field conditions.


Asunto(s)
Mariposas Nocturnas , Zea mays , Animales , Zea mays/genética , Zea mays/metabolismo , Benzoxazinas/metabolismo , Mariposas Nocturnas/fisiología , Larva , Genotipo , Herbivoria
20.
Pediatr Res ; 94(1): 378-384, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36585460

RESUMEN

BACKGROUND: Small-for-gestational-age (SGA) has a heterogeneous etiology. Our study aimed to examine the childhood health outcomes of etiology-distinct term SGA subgroups. METHODS: Data from the Collaborative Perinatal Project were used. The etiological factors of SGA were categorized into five groups: maternal, fetal, placental, environmental and physiological factors. Primary child outcomes included low IQ and growth restriction. A total of 8417 term infants were eligible. RESULTS: Compared with AGA, SGA children due to fetal factors had the highest risk of low IQ (aOR = 1.94, 95% CI: 1.45-2.59). SGA infants due to physiological factors had the highest risk of growth restriction (aOR = 6.04, 95% CI: 3.93-9.27). SGA children had a higher risk of growth restriction with the aOR ranging from 3.05 (95% CI: 2.36-3.96) to 5.77 (95% CI: 4.29-7.75) for the number of risk factors that the SGA infants had from 1 to 5. SGA children with any risk factor were associated with a higher risk of lower IQ with the aOR ranging from 1.59 (95% CI: 1.31-1.94) to 1.96 (95% CI: 1.50-2.55). SGA without the five types of etiologies was not associated with adverse child outcomes except for growth restriction (aOR = 3.82, 95% CI: 2.62-5.55). CONCLUSION: Term SGA of different etiologies may lead to different child health outcomes. IMPACT: Our study found that SGA of different etiologies may lead to different child health outcomes. Compared with AGA, SGA children due to fetal factors had the highest risk of low IQ. SGA infants due to physiological factors had the highest risk of growth restriction. SGA babies should not be treated the same. In the era of precision medicine, our findings may help pediatricians and parents better manage SGA babies according to different etiologies and the number of risk factors.


Asunto(s)
Recién Nacido Pequeño para la Edad Gestacional , Placenta , Recién Nacido , Lactante , Humanos , Niño , Embarazo , Femenino , Retardo del Crecimiento Fetal/etiología , Causalidad , Evaluación de Resultado en la Atención de Salud , Edad Gestacional
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