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1.
PLoS Pathog ; 20(5): e1011669, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38781259

RESUMEN

The virus severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, is the causative agent of the current COVID-19 pandemic. It possesses a large 30 kilobase (kb) genome that encodes structural, non-structural, and accessory proteins. Although not necessary to cause disease, these accessory proteins are known to influence viral replication and pathogenesis. Through the synthesis of novel infectious clones of SARS-CoV-2 that lack one or more of the accessory proteins of the virus, we have found that one of these accessory proteins, ORF8, is critical for the modulation of the host inflammatory response. Mice infected with a SARS-CoV-2 virus lacking ORF8 exhibit increased weight loss and exacerbated macrophage infiltration into the lungs. Additionally, infection of mice with recombinant SARS-CoV-2 viruses encoding ORF8 mutations found in variants of concern reveal that naturally occurring mutations in this protein influence disease severity. Our studies with a virus lacking this ORF8 protein and viruses possessing naturally occurring point mutations in this protein demonstrate that this protein impacts pathogenesis.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , SARS-CoV-2/genética , COVID-19/virología , COVID-19/inmunología , COVID-19/patología , COVID-19/genética , Ratones , Humanos , Progresión de la Enfermedad , Proteínas Virales/genética , Proteínas Virales/metabolismo , Pulmón/virología , Pulmón/patología , Replicación Viral , Neumonía/virología , Neumonía/patología , Chlorocebus aethiops , Mutación , Células Vero , Femenino
2.
Mol Cell ; 67(4): 594-607.e4, 2017 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-28735899

RESUMEN

Pervasive transcription initiates from cryptic promoters and is observed in eukaryotes ranging from yeast to mammals. The Set2-Rpd3 regulatory system prevents cryptic promoter function within expressed genes. However, conserved systems that control pervasive transcription within intergenic regions have not been well established. Here we show that Mot1, Ino80 chromatin remodeling complex (Ino80C), and NC2 co-localize on chromatin and coordinately suppress pervasive transcription in S. cerevisiae and murine embryonic stem cells (mESCs). In yeast, all three proteins bind subtelomeric heterochromatin through a Sir3-stimulated mechanism and to euchromatin via a TBP-stimulated mechanism. In mESCs, the proteins bind to active and poised TBP-bound promoters along with promoters of polycomb-silenced genes apparently lacking TBP. Depletion of Mot1, Ino80C, or NC2 by anchor away in yeast or RNAi in mESCs leads to near-identical transcriptome phenotypes, with new subtelomeric transcription in yeast, and greatly increased pervasive transcription in both yeast and mESCs.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Células Madre Embrionarias/enzimología , Fosfoproteínas/metabolismo , Proteínas Represoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética , ATPasas Asociadas con Actividades Celulares Diversas , Adenosina Trifosfatasas/genética , Sitios de Unión , Línea Celular , Proteínas de Unión al ADN , Eucromatina/genética , Eucromatina/metabolismo , Regulación Fúngica de la Expresión Génica , Silenciador del Gen , Genotipo , Heterocromatina/genética , Heterocromatina/metabolismo , Fenotipo , Fosfoproteínas/genética , Regiones Promotoras Genéticas , Unión Proteica , Interferencia de ARN , Proteínas Represoras/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Información Silente de Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Información Silente de Saccharomyces cerevisiae/metabolismo , Factores Asociados con la Proteína de Unión a TATA/genética , Proteína de Unión a TATA-Box/genética , Proteína de Unión a TATA-Box/metabolismo , Factor de Transcripción TFIID , Factores de Transcripción/genética , Transfección
3.
Proc Natl Acad Sci U S A ; 119(37): e2204717119, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36040867

RESUMEN

The ongoing COVID-19 pandemic is a major public health crisis. Despite the development and deployment of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pandemic persists. The continued spread of the virus is largely driven by the emergence of viral variants, which can evade the current vaccines through mutations in the spike protein. Although these differences in spike are important in terms of transmission and vaccine responses, these variants possess mutations in the other parts of their genome that may also affect pathogenesis. Of particular interest to us are the mutations present in the accessory genes, which have been shown to contribute to pathogenesis in the host through interference with innate immune signaling, among other effects on host machinery. To examine the effects of accessory protein mutations and other nonspike mutations on SARS-CoV-2 pathogenesis, we synthesized both viruses possessing deletions in the accessory genes as well as viruses where the WA-1 spike is replaced by each variant spike gene in a SARS-CoV-2/WA-1 infectious clone. We then characterized the in vitro and in vivo replication of these viruses and compared them to both WA-1 and the full variant viruses. Our work has revealed that the accessory proteins contribute to SARS-CoV-2 pathogenesis and the nonspike mutations in variants can contribute to replication of SARS-CoV-2 and pathogenesis in the host. This work suggests that while spike mutations may enhance receptor binding and entry into cells, mutations in accessory proteins may alter clinical disease presentation.


Asunto(s)
COVID-19 , Mutación , SARS-CoV-2 , Proteínas Reguladoras y Accesorias Virales , Virulencia , COVID-19/virología , Humanos , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/genética , Proteínas Reguladoras y Accesorias Virales/genética , Virulencia/genética , Replicación Viral/genética
4.
Genes Dev ; 31(3): 241-246, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28270516

RESUMEN

Chromobox homolog 3 (Cbx3/heterochromatin protein 1γ [HP1γ]) stimulates cell differentiation, but its mechanism is unknown. We found that Cbx3 binds to gene promoters upon differentiation of murine embryonic stem cells (ESCs) to neural progenitor cells (NPCs) and recruits the Mediator subunit Med26. RNAi knockdown of either Cbx3 or Med26 inhibits neural differentiation while up-regulating genes involved in mesodermal lineage decisions. Thus, Cbx3 and Med26 together ensure the fidelity of lineage specification by enhancing the expression of neural genes and down-regulating genes specific to alternative fates.


Asunto(s)
Diferenciación Celular , Linaje de la Célula , Proteínas Cromosómicas no Histona/metabolismo , Células Madre Embrionarias/citología , Regulación de la Expresión Génica , Complejo Mediador/metabolismo , Células-Madre Neurales/citología , Animales , Células Cultivadas , Proteínas Cromosómicas no Histona/antagonistas & inhibidores , Proteínas Cromosómicas no Histona/genética , Quinasa 8 Dependiente de Ciclina/genética , Quinasa 8 Dependiente de Ciclina/metabolismo , Células Madre Embrionarias/metabolismo , Complejo Mediador/genética , Mesodermo/citología , Mesodermo/metabolismo , Ratones , Células-Madre Neurales/metabolismo , Regiones Promotoras Genéticas , ARN Interferente Pequeño/genética
5.
Nutr Metab Cardiovasc Dis ; 34(7): 1631-1638, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38653673

RESUMEN

BACKGROUND AND AIMS: It has been reported that maresin 1 (MaR1) is able to protect against the development of atherogenesis in cellular and animal models. This study was performed to investigate whether plasma MaR1 is associated with the risk of atherosclerotic cardiovascular disease (ASCVD) at the population level. METHODS AND RESULTS: The study included 2822 non-ASCVD participants from a community-based cohort who were followed for about 8 years. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for ASCVD events according to baseline MaR1 quartiles were calculated using the Cox proportional hazards model. During follow-up, a total of 290 new ASCVD cases were identified. The restricted cubic spline analysis indicated a linear dose-response association between plasma MaR1 and incident ASCVD. In addition, the adjusted-HR (95% CI) for ASCVD events associated with one standard deviation increase in MaR1 was 0.79 (0.68-0.91). Moreover, the adjusted-HRs (95% CIs) for ASCVD events associated with the second, third and fourth quartiles versus the first quartile of plasma MaR1 were 1.00, 1.04 (0.76, 1.42), 0.88 (0.64, 1.22) and 0.58 (0.41, 0.84), respectively. Mediation analyses showed that the association between MaR1 and incident ASCVD was partially mediated by small dense low-density lipoprotein cholesterol, with a mediation proportion of 9.23%. Further, the net reclassification improvement and integrated discrimination improvement of ASCVD risk were significantly improved when MaR1 was added to basic model established by conventional risk factors (all p < 0.01). CONCLUSIONS: Elevated plasma MaR1 concentrations are associated with a lower risk of ASCVD development.


Asunto(s)
Aterosclerosis , Biomarcadores , Ácidos Docosahexaenoicos , Humanos , Masculino , Femenino , Persona de Mediana Edad , Aterosclerosis/epidemiología , Aterosclerosis/sangre , Aterosclerosis/diagnóstico , Medición de Riesgo , Incidencia , China/epidemiología , Biomarcadores/sangre , Anciano , Factores de Tiempo , Ácidos Docosahexaenoicos/sangre , Adulto , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Factores Protectores , Pueblos del Este de Asia
6.
Ecotoxicol Environ Saf ; 283: 116870, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39137467

RESUMEN

The biogeochemical processes of sulfur and heavy metals in the environment are closely related to each other. We investigated the influence of sulfur addition on hyperaccumulator Sedum alfredii Hance growth, cadmium (Cd) accumulation, soil Cd bioavailability, soil bacterial communities and plant transcriptome responses. The results showed that an appropriate rate of sulfur addition (1.0 or 2.5 g/kg) enhanced the growth of Sedum alfredii Hance plants as well as their accumulation of Cd. A high rate of sulfur addition (5.0 or 10.0 g/kg) causes toxicity to Sedum alfredii Hance plants. The application of an appropriate amount of sulfur to the soil increased the abundance of sulfur-oxidizing bacteria such as Sulfuriferula and Thiobacillus; acid-fast bacillus such as Alicyclobacillus; and cadmium-tolerant bacteria such as Bacillus and Rhodanobacter. This led to a decrease in pH and an increase in bioavailable Cd in the soil. RNA sequencing revealed that the addition of sulfur to soils led to the up regulation of most of the differentially expressed genes (DEGs) involved in "photosynthesis" and "photosynthesis, light reaction" in Sedum alfredii Hance leaves. Moreover, the "plant hormone signal transduction" pathway was significantly enriched with sulfur addition. Sulfur assimilation in Sedum alfredii Hance plants may promote photosynthesis and hormone synthesis, leading to Cd tolerance in these plants. Our study revealed that sulfur fertilization enhanced the efficiency of Cd phytoremediation in Sedum alfredii Hance plants.

7.
J Environ Manage ; 361: 121197, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38820791

RESUMEN

Heavy metal pollution of agricultural soil is a major global concern, prompting the establishment of maximum allowable limits (MALs) to ensure food safety and protect human health. This study collected and compared MALs for six heavy metals (As, Cd, Hg, Pb, Zn, and Cu) in agricultural soils from representative countries and organizations (EU and WHO/FAO). The research evaluated the critical health risks and efficacy of these MALs under the hypothetical scenario of metals concentrations reaching the maximum allowable level. Safe thresholds for heavy metals were then derived based on maximum acceptable health risk levels. The comparative analysis revealed significant variations in the specific limit values and terms of MALs across countries and organizations, even for the same metal. This suggests that there is no consensus among countries and organizations regarding the level of metal-related health risks. Furthermore, the risk analysis of metal concentrations reaching the maximum level accentuated heightened risks associated with As, suggesting that the current risk of soil As exposure was underestimated, particularly for children. However, soil Cu, Cd, and Zn limits generally resulted in low health risks, implying that the current limits may overestimate their hazard. Overall, the results highlight that the current MALs for soil heavy metals may not fully safeguard human health. There is a critical need to optimize current soil MALs based on localized risks and the actual impact of these metals on human health. It is suggested to appropriately lower the limits of metals (such as As) whose impact on health risks is underestimated, and cautiously increase the limits of metals (such as Cu, Cd, and Zn) that currently pose minor health risks. This approach aims to reduce both over and insufficient protection problems of soil heavy metal MALs, emphasizing the importance of considering the locality in setting these limits.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Suelo , Metales Pesados/análisis , Medición de Riesgo , Contaminantes del Suelo/análisis , Humanos , Suelo/química , Monitoreo del Ambiente
8.
Yi Chuan ; 46(1): 3-17, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38230453

RESUMEN

As an intraspecific outcrossing mechanism, self-incompatibility (SI) widely adopted by hermaphroditic plants is usually controlled by a polymorphic multi-allelic S locus. Typically, six molecular types of SI have been found, including type-I controlled by the pistil S S-RNase and pollen S SLFs commonly spread in Plantaginaceae, Solanaceae, Rosaceae and Rutaceae, type-II by SRK and SCR in Brassicaceae, type-III by PrsS and PrpS in Papaveraceae, type-IV by CYP-GLO2-KFB-CCM-PUM in Primulaceae, type-V by TsSPH1-TsYUC6-TsBAHD in Turneraceae and type-VI by HPS10-S and DUF247I-S in Poaceae, with type-I characterized as a non-self recognition system but types-II, -III and -VI self ones. Furthermore, remarkable progresses have been made in their origin and evolutionary mechanisms recently. Among them, type-I SI possessed a single origin in the most recent common ancestor of eudicots and types II-V dynamically evolved following its losses, while type-VI SI exclusively existed in monocot Poaceae may be regained after the loss of the ancient type-I. Here, we mainly review the molecular and evolutionary mechanisms of angiosperm SI systems, thus providing a helpful reference for their theoretical research and breeding application.


Asunto(s)
Magnoliopsida , Autoincompatibilidad en las Plantas con Flores , Magnoliopsida/genética , Autoincompatibilidad en las Plantas con Flores/genética , Fitomejoramiento , Evolución Biológica , Polen , Proteínas de Plantas/genética
9.
Purinergic Signal ; 19(1): 69-85, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35113324

RESUMEN

Our and in vitro studies had confirmed that mechanosensitive ATP release and accumulation in acupoints was elicited by acupuncture (AP), which might be a pivotal step for triggering AP analgesia. But to date, the dynamics of extracellular ATP (eATP) in the interstitial space during AP process was poorly known, mainly due to the low temporal resolution of the current detection approach. This study attempted to capture rapid eATP signals in vivo in the process of needling, and further explored the role of this eATP mobilization in initiating AP analgesic effect. Ipsilateral 20-min needling was applied on Zusanli acupoint (ST36) of complete Freund's adjuvant (CFA)-induced ankle arthritis rats. Pain thresholds were assessed in injured-side hindpaws. eATP in the interstitial space was microdialyzed and real-time quantified by luciferin-luciferase assay at 1-min interval with the aid of the microfluid chip. We revealed in behavioral tests that modulation of eATP levels in ST36 influenced AP analgesic effect on ankle arthritis. A transient eATP accumulation was induced by needling that started to mobilize at 4 min, climbed to the peak of 11.21 nM within 3.25 min and gradually recovered. Such AP-induced eATP mobilization was significantly impacted by ankle inflammation, needling depth, needle manipulation, and the presence of local ecto-nucleotidases. This work reveals that needling elicits a transient eATP mobilization in acupoints, which contributes to initiating AP analgesia. This study will help us better understand the peripheral mechanism of AP analgesia and guide clinicians to optimize the needle manipulations to improve AP efficacy.


Asunto(s)
Analgesia por Acupuntura , Terapia por Acupuntura , Artritis , Ratas , Animales , Puntos de Acupuntura , Analgésicos , Adenosina Trifosfato
10.
Mol Cell ; 60(3): 342-3, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26545072

RESUMEN

In this issue of Molecular Cell, Kubik et al. (2015) describe how the RSC chromatin remodeling complex collaborates with two DNA sequence motifs and sequence-specific general regulatory factors to assemble fragile nucleosomes at highly transcribed yeast Pol II promoters, and they distinguish these from promoters bearing stable nucleosomes.


Asunto(s)
Regulación Fúngica de la Expresión Génica/fisiología , Nucleosomas/metabolismo , Regiones Promotoras Genéticas/fisiología , Proteínas de Saccharomyces cerevisiae/biosíntesis , Saccharomyces cerevisiae/metabolismo
11.
Sensors (Basel) ; 24(1)2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-38203082

RESUMEN

Monitoring the biochemical pigment contents in individual plants is crucial for assessing their health statuses and physiological states. Fast, low-cost measurements of plants' biochemical traits have become feasible due to advances in multispectral imaging sensors in recent years. This study evaluated the field application of proximal multispectral imaging combined with feature selection and regressive analysis to estimate the biochemical pigment contents of poplar leaves. The combination of 6 spectral bands and 26 vegetation indices (VIs) derived from the multispectral bands was taken as the group of initial variables for regression modeling. Three variable selection algorithms, including the forward selection algorithm with correlation analysis (CORR), recursive feature elimination algorithm (RFE), and sequential forward selection algorithm (SFS), were explored as candidate methods for screening combinations of input variables from the 32 spectral-derived initial variables. Partial least square regression (PLSR) and nonlinear support vector machine regression (SVR) were both applied to estimate total chlorophyll content (Chla+b) and carotenoid content (Car) at the leaf scale. The results show that the nonlinear SVR prediction model based on optimal variable combinations, selected by SFS using multiple scatter correction (MSC) preprocessing data, achieved the best estimation accuracy and stable prediction performance for the leaf pigment content. The Chla+b and Car models developed using the optimal model had R2 and RMSE predictive statistics of 0.849 and 0.825 and 5.116 and 0.869, respectively. This study demonstrates the advantages of using a nonlinear SVR model combined with SFS variable selection to obtain a more reliable estimation model for leaf biochemical pigment content.


Asunto(s)
Algoritmos , Populus , Carotenoides , Clorofila , Diagnóstico por Imagen , Hojas de la Planta
12.
Sensors (Basel) ; 23(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36904931

RESUMEN

In this study, the measurement characteristics of speckles based on the photoinduced electromotive force (photo-emf) effect for high-frequency, small-amplitude, and in-plane vibration were theoretically and experimentally studied. The relevant theoretical models were utilized. A GaAs crystal was used as the photo-emf detector for experimental research, as well as to study the influence of the amplitude and frequency of the vibration, the imaging magnification of the measuring system, and the average speckle size of the measuring light on the first harmonic of the induced photocurrent in the experiments. The correctness of the supplemented theoretical model was verified, and a theoretical and experimental basis was provided for the feasibility of using GaAs to measure in-plane vibrations with nanoscale amplitudes.

13.
Genes Dev ; 29(4): 350-5, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25691465

RESUMEN

Here we show that the Ino80 chromatin remodeling complex (Ino80C) directly prevents euchromatin from invading transcriptionally silent chromatin within intergenic regions and at the border of euchromatin and heterochromatin. Deletion of Ino80C subunits leads to increased H3K79 methylation and noncoding RNA polymerase II (Pol II) transcription centered at the Ino80C-binding sites. The effect of Ino80C is direct, as it blocks H3K79 methylation by Dot1 in vitro. Heterochromatin stimulates the binding of Ino80C in vitro and in vivo. Our data reveal that Ino80C serves as a general silencing complex that restricts transcription to gene units in euchromatin.


Asunto(s)
Cromatina/genética , Eucromatina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sitios de Unión , Eucromatina/genética , Regulación Fúngica de la Expresión Génica , Silenciador del Gen , N-Metiltransferasa de Histona-Lisina/metabolismo , Metilación , Proteínas Nucleares/metabolismo , Unión Proteica , ARN Polimerasa II/metabolismo
14.
BMC Genomics ; 23(1): 90, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35100986

RESUMEN

BACKGROUND: Members of the genus Novius Mulsant, 1846 (= Rodolia Mulsant, 1850) (Coleoptera, Coccinellidae), play important roles in the biological control of cotton cushion scale pests, especially those belonging to Icerya. Since the best-known species, the vedalia beetle Novius cardinalis (Mulsant, 1850) was introduced into California from Australia, more than a century of successful use in classical biological control, some species of Novius have begun to exhibit some field adaptations to novel but related prey species. Despite their economic importance, relatively little is known about the underlying genetic adaptations associated with their feeding habits. Knowledge of the genome sequence of Novius is a major step towards further understanding its biology and potential applications in pest control. RESULTS: We report the first high-quality genome sequence for Novius pumilus (Weise, 1892), a representative specialist of Novius. Computational Analysis of gene Family Evolution (CAFE) analysis showed that several orthogroups encoding chemosensors, digestive, and immunity-related enzymes were significantly expanded (P < 0.05) in N. pumilus compared to the published genomes of other four ladybirds. Furthermore, some of these orthogroups were under significant positive selection pressure (P < 0.05). Notably, transcriptome profiling demonstrated that many genes among the significantly expanded and positively selected orthogroups, as well as genes related to detoxification were differentially expressed, when N. pumilus feeding on the nature prey Icerya compared with the no feeding set. We speculate that these genes are vital in the Icerya adaptation of Novius species. CONCLUSIONS: We report the first Novius genome thus far. In addition, we provide comprehensive transcriptomic resources for N. pumilus. The results from this study may be helpful for understanding the association of the evolution of genes related to chemosensing, digestion, detoxification and immunity with the prey adaptation of insect predators. This will provide a reference for future research and utilization of Novius in biological control programs. Moreover, understanding the possible molecular mechanisms of prey adaptation also inform mass rearing of N. pumilus and other Novius, which may benefit pest control.


Asunto(s)
Escarabajos , Hemípteros , Animales , Agentes de Control Biológico , Escarabajos/genética , Genómica , Insectos
15.
BMC Plant Biol ; 22(1): 514, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36329386

RESUMEN

BACKGROUND: Grazing disturbance usually affects floral display and pollination efficiency in the desert steppe, which may cause pollen limitation in insect-pollinated plants. Effective pollination is essential for the reproductive success of insect-pollinated plants and insufficient pollen transfer may result in pollen limitation. Caragana microphylla Lam is an arid region shrub with ecological importance. Few studies have been conducted on how grazing disturbance influences pollen limitation and pollination efficiency of C. microphylla. Here, we quantify the effect of different grazing intensities on floral display, pollinator visitation frequency and seed production in the Urat desert steppe. RESULTS: In C. microphylla, supplemental hand pollination increased the seed set, and pollen limitation was the predominant limiting factor. As the heavy grazing significantly reduced the seed set in plants that underwent open-pollination, but there was no significant difference in the seed set between plants in the control plots and plants in the moderate grazing plots. Furthermore, there was a higher pollinator visitation frequency in plants in the control plots than in plants in the heavy grazing plots. CONCLUSIONS: We found that pollinator visitation frequency was significantly associated with the number of open flowers. Our findings also demonstrated that seed production is associated with pollinator visitation frequency, as indicated by increased seed production in flowers with higher pollinator visitation frequency. Therefore, this study provides insight into the effect of different grazing intensities on floral display that are important for influencing pollinator visitation frequency and pollination efficiency in desert steppes.


Asunto(s)
Flores , Herbivoria , Insectos , Polen , Polinización , Animales , Flores/fisiología , Insectos/fisiología , Plantas/parasitología , Polinización/fisiología , Clima Desértico , Herbivoria/fisiología
16.
Nutr Cancer ; 74(10): 3735-3746, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35758096

RESUMEN

This study aimed to formulate Kappaphycus alvarezii compound powder containing Kappaphycus alvarezii powder (KP), cooked sorghum powder (SP), and longan powder (LP); which was evaluated for its therapeutic effects against chemotherapy-induced intestinal mucosal injury (CIMI). Based on rheological properties, sensory evaluation, and antioxidant activity and using single factor and response surface methodology, the optimal formula to develop the compound powder was determined to be 35% KP, 30% SP, 5% LP, and 30% xylitol. Thereafter, the efficacy of the compound powder was tested by feeding BALB/c mice with diets supplemented with the Kappaphycus alvarezii compound powder (3% and 5%) for 14 consecutive days. The chemotherapeutic drug 5-fluorouracil was intraperitoneally injected (50 mg/kg) in the mice to induce CIMI for the last three consecutive days. Compared to the CIMI mice, those fed 5% Kappaphycus alvarezii compound powder (HC) showed significantly improved the intestinal injury, increased mucin-2 secretion, and reduced TNF-α, IL-1ß, IL-6, LT, and COX-2 levels. Furthermore, HC intake significantly reduced the Firmicutes-to-Bacteroidetes ratio, promoted the growth of beneficial bacteria, such as Alloprevotella, and inhibited the growth of harmful bacteria, such as Clostridium. In conclusion, HC has a protective effect against CIMI and provides a novel dietary strategy for patients undergoing chemotherapy.


Asunto(s)
Antineoplásicos , Mucositis , Rhodophyta , Animales , Antineoplásicos/toxicidad , Fluorouracilo/toxicidad , Mucosa Intestinal , Ratones , Ratones Endogámicos BALB C , Mucositis/inducido químicamente , Mucositis/tratamiento farmacológico , Mucositis/prevención & control , Polvos/efectos adversos
17.
Crit Rev Food Sci Nutr ; 62(19): 5322-5348, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33591238

RESUMEN

Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide), a well-known vanilloid, which is the main spicy component in chili peppers, showing several biological activities and the potential applications range from food flavorings to therapeutics. Traditional extraction of capsaicin by organic solvents was time-consuming, some new methods such as aqueous two-phase method and ionic liquid extraction method have been developed. During past few decades, an ample variety of biological effects of capsaicin have been evaluated. Capsaicin can be used in biofilms and antifouling coatings due to its antimicrobial activity, allowing it has a promising application in food packaging, food preservation, marine environment and dental therapy. Capsaicin also play a crucial role in metabolic disorders, including weight loss, pressure lowing and insulin reduction effects. In addition, capsaicin was identified effective on preventing human cancers, such as lung cancer, stomach cancer, colon cancer and breast cancer by inducing apoptosis and inhibiting cell proliferation of tumor cells. Previous research also suggest the positive effects of capsaicin on pain relief and cognitive impairment. Capsaicin, the agonist of transient receptor potential vanilloid type 1 (TRPV1), could selectively activate TRPV1, inducing Ca2+ influx and related signaling pathways. Recently, gut microbiota was also involved in some diseases therapeutics, but its influence on the effects of capsaicin still need to be deeply studied. In this review, different extraction and purification methods of capsaicin, its biological activities and pharmacological effects were systematically summarized, as well as the possible mechanisms were also deeply discussed. This article will give an updated and better understanding of capsaicin-related biological effects and provide theoretical basis for its further research and applications in human health and manufacture development.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Capsicum , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Capsaicina/farmacología , Capsaicina/uso terapéutico , Femenino , Humanos
18.
Nature ; 531(7593): 241-4, 2016 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-26863186

RESUMEN

Sexual reproduction requires recognition between the male and female gametes. In flowering plants, the immobile sperms are delivered to the ovule-enclosed female gametophyte by guided pollen tube growth. Although the female gametophyte-secreted peptides have been identified to be the chemotactic attractant to the pollen tube, the male receptor(s) is still unknown. Here we identify a cell-surface receptor heteromer, MDIS1-MIK, on the pollen tube that perceives female attractant LURE1 in Arabidopsis thaliana. MDIS1, MIK1 and MIK2 are plasma-membrane-localized receptor-like kinases with extracellular leucine-rich repeats and an intracellular kinase domain. LURE1 specifically binds the extracellular domains of MDIS1, MIK1 and MIK2, whereas mdis1 and mik1 mik2 mutant pollen tubes respond less sensitively to LURE1. Furthermore, LURE1 triggers dimerization of the receptors and activates the kinase activity of MIK1. Importantly, transformation of AtMDIS1 to the sister species Capsella rubella can partially break down the reproductive isolation barrier. Our findings reveal a new mechanism of the male perception of the female attracting signals.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fosfotransferasas/metabolismo , Receptores de Superficie Celular/metabolismo , Transducción de Señal , Arabidopsis/genética , Arabidopsis/fisiología , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Capsella/genética , Capsella/metabolismo , Capsella/fisiología , Membrana Celular/metabolismo , Mutación , Óvulo Vegetal/metabolismo , Fenotipo , Fosfotransferasas/química , Fosfotransferasas/genética , Tubo Polínico/genética , Tubo Polínico/crecimiento & desarrollo , Tubo Polínico/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Multimerización de Proteína , Proteínas Serina-Treonina Quinasas , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Receptores de Superficie Celular/química , Receptores de Superficie Celular/genética , Reproducción
19.
BMC Biol ; 19(1): 7, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33446206

RESUMEN

BACKGROUND: Horizontal gene transfer (HGT) has been documented in many herbivorous insects, conferring the ability to digest plant material and promoting their remarkable ecological diversification. Previous reports suggest HGT of antibacterial enzymes may have contributed to the insect immune response and limit bacterial growth. Carnivorous insects also display many evolutionary successful lineages, but in contrast to the plant feeders, the potential role of HGTs has been less well-studied. RESULTS: Using genomic and transcriptomic data from 38 species of ladybird beetles, we identified a set of bacterial cell wall hydrolase (cwh) genes acquired by this group of beetles. Infection with Bacillus subtilis led to upregulated expression of these ladybird cwh genes, and their recombinantly produced proteins limited bacterial proliferation. Moreover, RNAi-mediated cwh knockdown led to downregulation of other antibacterial genes, indicating a role in antibacterial immune defense. cwh genes are rare in eukaryotes, but have been maintained in all tested Coccinellinae species, suggesting that this putative immune-related HGT event played a role in the evolution of this speciose subfamily of predominant predatory ladybirds. CONCLUSION: Our work demonstrates that, in a manner analogous to HGT-facilitated plant feeding, enhanced immunity through HGT might have played a key role in the prey adaptation and niche expansion that promoted the diversification of carnivorous beetle lineages. We believe that this represents the first example of immune-related HGT in carnivorous insects with an association with a subsequent successful species radiation.


Asunto(s)
Antibiosis/genética , Evolución Biológica , Escarabajos/genética , Transferencia de Gen Horizontal , Genes Bacterianos , Genes de Insecto , Adaptación Biológica , Animales , Pared Celular/química , Pared Celular/enzimología , Escarabajos/enzimología , Interacciones Huésped-Patógeno , Hidrolasas/genética
20.
Bioprocess Biosyst Eng ; 45(2): 353-364, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34797400

RESUMEN

The combined cross-linked enzyme aggregates (combi-CLEAs) containing galactitol dehydrogenase (Gdh) and NADH oxidase (Nox) were prepared for L-tagatose synthesis. To prevent the excess consumption of cofactor, Nox in the combi-CLEAs was used to in situ regenerate NAD+. In the immobilization process, ammonia sulfate and glutaraldehyde were used as the precipitant and cross-linking reagent, respectively. The preparation conditions were optimized as follows: 60% ammonium sulfate, 1:1 (molar ratio) of Gdh to Nox, 20:1 (molar ratio) of protein to glutaraldehyde, and 6 h of cross-linking time at 35 °C. Under these conditions, the activity of the combi-CLEAs was 210 U g-1. The combi-CLEAs exhibited higher thermostability and preserved 51.5% of the original activity after eight cycles of reuses at 45 °C. The combi-CLEAs were utilized for the preparation of L-tagatose without by-products. Therefore, the combi-CLEAs have the industrial potential for the bioconversion of galactitol to L-tagatose.


Asunto(s)
Enzimas Inmovilizadas , Hexosas , Regeneración , Reactivos de Enlaces Cruzados , Estabilidad de Enzimas , Enzimas Inmovilizadas/metabolismo , Hexosas/biosíntesis , Hexosas/química , Complejos Multienzimáticos , NADH NADPH Oxidorreductasas , Deshidrogenasas del Alcohol de Azúcar
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