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1.
Pestic Biochem Physiol ; 203: 106009, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39084775

RESUMEN

Fall armyworm, Spodoptera frugiperda (J. E. Smith), is a widely recognized global agricultural pest that has significantly reduced crop yields all over the world. S. frugiperda has developed resistance to various insecticides. Insect cytochrome P450 monooxygenases (CYPs or P450s) play an important role in detoxifying insecticides, leading to increased resistance in insect populations. However, the function of the specific P450 gene for lambda-cyhalothrin resistance in S. frugiperda was unclear. Herein, the expression patterns of 40 P450 genes in the susceptible and lambda-cyhalothrin-resistant populations were analyzed. Among them, CYP321A7 was found to be overexpressed in the resistant population, specifically LRS (resistance ratio = 25.38-fold) derived from a lambda-cyhalothrin-susceptible (SS) population and FLRS (a population caught from a field, resistance ratio = 63.80-fold). Elevated enzyme activity of cytochrome P450 monooxygenases (P450s) was observed for LRS (2.76-fold) and the FLRS (4.88-fold) as compared to SS, while no significant differences were observed in the activities of glutathione S-transferases and esterases. Furthermore, the knockdown of CYP321A7 gene by RNA interference significantly increased the susceptibility to lambda-cyhalothrin. Remarkably, the knockdown of CYP321A7 reduced the enzymatic activity of P450 by 43.7%, 31.9%, and 22.5% in SS, LRS, and FLRS populations, respectively. Interestingly, fourth-instar larvae treated with lambda-cyhalothrin at the LC30 dosage had a greater mortality rate due to RNA interference-induced suppression of CYP321A7 (with increases of 61.1%, 50.0%, and 45.6% for SS, LRS, and FLRS populations, respectively). These findings suggest a link between lambda-cyhalothrin resistance and continual overexpression of CYP321A7 in S. frugiperda larvae, emphasizing the possible importance of CYP321A7 in lambda-cyhalothrin detoxification in S. frugiperda.


Asunto(s)
Sistema Enzimático del Citocromo P-450 , Resistencia a los Insecticidas , Insecticidas , Nitrilos , Piretrinas , Spodoptera , Animales , Piretrinas/farmacología , Piretrinas/toxicidad , Spodoptera/efectos de los fármacos , Spodoptera/genética , Nitrilos/toxicidad , Nitrilos/farmacología , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Insecticidas/farmacología , Insecticidas/toxicidad , Resistencia a los Insecticidas/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Interferencia de ARN , Inactivación Metabólica , Larva/efectos de los fármacos , Larva/genética
2.
Phys Chem Chem Phys ; 25(3): 2462-2467, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36601881

RESUMEN

We report the structure, magnetic and electrical/thermal transport properties of the antiferromagnet MnSn2. Importantly, the existence of the two antiferromagnetic states below TN2 (∼320 K) is confirmed by magnetism and electrical transport measurements. An unsaturated positive magnetoresistance up to 150% at ∼9 T was observed at 5 K, whereas the magnetoresistance becomes negative in the whole range at high temperatures (T > 74 K). Systematic investigations of the Hall transport and thermoelectric properties reveal that the hole-type carriers are the majority carriers in MnSn2. The kink around 320 K in the Seebeck coefficient originates from the effect of the antiferromagnetic phase on the band structure, while the pronounced peak around 231 K is attributed to the phonon-drag effect. The results suggest that the spin arrangement plays a vital role in the magnetic, electrical, and thermal transport properties in MnSn2.

3.
BMC Musculoskelet Disord ; 24(1): 641, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37559076

RESUMEN

BACKGROUND: After the COVID-19 outbreak, many Chinese high school students have increased their dependence on electronic devices for studying and life, which may affect the incidence of neck and shoulder pain (NSP) in Chinese adolescents. METHODS: To evaluate the prevalence of NSP in high school students and its associated risk factors during COVID-19, a survey was conducted among 5,046 high school students in Shanghai, Qinghai, Henan and Macao during the second semester and summer vacation of the 2019-2020 academic year. The questionnaire included questions regarding demographic characteristics, the prevalence of NSP and lifestyle factors such as sedentary behavior, poor posture and electronic device usage. Univariable and multivariable logistic regression was used to analyze the possible influencing factors for neck and shoulder pain. RESULTS: A total of 4793 valid questionnaires (95.0%) were collected. The results indicated that the prevalence of NSP was 23.7% among high school students. Binary logistic regression analysis revealed that female gender (P < 0.05, OR = 1.82), grade (P < 0.05, range OR 1.40-1.51) and subject selection (P < 0.05, range OR 0.49-0.68) were risk factors for NSP in high school students. Sedentary behavior (P < 0.05, range OR 1.74-2.36), poor posture (P < 0.05, range OR 1.19-2.56), backpack weight (P < 0.05, range OR 1.17-1.88), exercise style and frequency (P < 0.05, range OR 1.18-1.31; P < 0.05, range OR 0.76-0.79, respectively), and the time spent using electronic devices (P < 0.05, range OR 1.23-1.38)had a significant correlation with NSP in high school students. CONCLUSIONS: NSP is currently very common among high school students during the outbreak of COVID-19. Sedentary behavior, poor posture and other factors have a great impact on the occurrence of NSP in high school students. Education regarding healthy lifestyle choices should be advocated for to decrease NSP among high school students, such as more physical activity, changing poor postures and reducing the amount of time spent using electronic devices.


Asunto(s)
COVID-19 , Dolor de Hombro , Adolescente , Humanos , Femenino , Dolor de Hombro/diagnóstico , Dolor de Hombro/epidemiología , Dolor de Hombro/etiología , Estudios Transversales , Dolor de Cuello/etiología , Prevalencia , China/epidemiología , COVID-19/epidemiología , Factores de Riesgo , Estudiantes , Encuestas y Cuestionarios
4.
Anim Biotechnol ; 34(7): 3063-3073, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36244042

RESUMEN

PDZK1-interacting protein 1(PDZK1IP1), also known as MAP17, is encoded by the PDZK1IP1 gene and is a membrane-associated protein. PDZK1IP1 have been proven to be a potent regulator of cancer cell proliferation. However, the role of PDZK1IP1 in regulating goat subcutaneous preadipocyte proliferation is unknown. Here, we cloned the full-length coding sequence of PDZK1IP1 gene, investigated the potential functional of PDZK1IP1 in goat subcutaneous preadipocyte proliferation by gaining or losing function in vitro. Our results indicated that goat PDZK1IP1 gene consists of 345 bp, encoding a protein of 114 amino acids containing a typical PDZK1IP1 (MAP17) super family domain. Overexpression of PDZK1IP1 significantly increased the number of EdU-positive cells and cell viability, and also upregulated mRNA expression of cell proliferation-associated genes including CCND1 and CDK2 in vitro cultured cells. Conversely, knockdown of PDZK1IP1 mediated by siRNA technique significantly inhibited subcutaneous preadipocyte proliferation and downregulated mRNA expression of cell proliferation-associated genes including CCNE1, CCND1 and CDK2. Collectively, these results suggested that PDZK1IP1 can promote proliferation of goat subcutaneous preadipocyte.


Asunto(s)
Cabras , Factores de Transcripción , Animales , Cabras/fisiología , Células Cultivadas , Factores de Transcripción/metabolismo , Proliferación Celular/genética , ARN Mensajero/metabolismo
5.
Ecotoxicol Environ Saf ; 267: 115669, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37944464

RESUMEN

Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is one of the most destructive insect pests owned strong resistance to different insecticides. Indoxacarb as a novel oxadiazine insecticide becomes the main pesticide against S. litura. DIMBOA [2,4-dihydroxy-7-methoxy-2 H-1,4-benz-oxazin-3(4 H)-one] is involved in important chemical defense processes in corn plants. However, the insects' adaptation mechanism to insecticides when exposed to defensive allelochemicals in their host plants remains unclear. Here, we assessed multi-resistance, and resistance mechanisms based on S. litura life history traits. After 18 generations of selection, indoxacarb resistance was increased by 61.95-fold (Ind-Sel) and 86.06-fold (Dim-Sel) as compared to the Lab-Sus. Also, DIMBOA-pretreated larvae developed high resistance to beta-cypermethrin, chlorpyrifos, phoxim, chlorantraniliprole, and emamectin benzoate. Meanwhile, indoxacarb (LC50) was applied to detect its impact on thirty-eight detoxification-related genes expression. The transcripts of SlituCOE073, SlituCOE009, SlituCOE074, and SlituCOE111 as well as SlGSTs5, SlGSTu1, and SlGSTe13 were considerably raised in the Ind-Sel strain. Among the twenty-three P450s, CYP6AE68, CYP321B1, CYP6B50, CYP9A39, CYP4L10, and CYP4S9v1 transcripts denoted significantly higher levels in the Ind-Sel strain, suggesting that CarEs, GSTs and P450s genes may be engaged in indoxacarb resistance. These outcomes further highlighted the importance of detoxification enzymes for S. litura gene expression and their role in responses to insecticides and pest management approaches.


Asunto(s)
Insecticidas , Animales , Spodoptera/fisiología , Insecticidas/farmacología , Nicotiana/metabolismo , Benzoxazinas , Larva/metabolismo , Expresión Génica , Resistencia a los Insecticidas/genética
6.
Pestic Biochem Physiol ; 187: 105215, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36127062

RESUMEN

Herbivore-induced plant volatiles (HIPVs) have been associated with plant-plant-herbivorous-natural enemies communication and an enhanced response to the subsequent attack. Spodoptera litura is a serious cosmopolitan pest that has developed a high level of resistance to many insecticides. However, the underlying molecular and biochemical mechanism by which HIPV priming reduces S. litura larval sensitivity to insecticides remains largely unknown. This study was conducted to explore the potential of volatile from undamaged, or artificially damaged, or S. litura-damaged tomato plants on the susceptibility of S. litura to the insecticides beta-cypermethrin indoxacarb and chlorpyrifos. We found that larvae exposed to volatile from S. litura-damaged or artificially damaged tomato plants were significantly less susceptible to the three insecticides than those exposed to volatile from undamaged tomato plants. Elevated activities of detoxifying enzymes [cytochrome P450 monooxygenases (P450s), glutathione S-transferases (GSTs), and esterases (ESTs)], were expressed in S. litura larvae exposed to volatile from S. litura-damaged tomato plants than those exposed to volatile from undamaged tomato plants. Similarly, seven detoxification-related genes [GSTs (SlGSTe1, SlGSTo1, and SlGSTe3) and P450s (CYP6B48, CYP9A40, CYP321A7, and CYP321B1)] in the midgut and fat body of larvae were up-regulated under exposure to volatile from S. litura-damaged tomato plants. Increased volatile organic compounds emissions were detected in the headspace of tomato plants damaged by S. litura compared to the undamaged plants. Collectively, these findings suggest that HIPVs can considerably reduce caterpillar susceptibility to insecticides, possibly through induction-enhanced detoxification mechanisms, and provide valuable information for implementing an effective integrated pest management strategy.


Asunto(s)
Cloropirifos , Insecticidas , Solanum lycopersicum , Compuestos Orgánicos Volátiles , Animales , Cloropirifos/farmacología , Sistema Enzimático del Citocromo P-450/genética , Esterasas , Glutatión , Herbivoria , Insecticidas/toxicidad , Larva , Spodoptera , Transferasas/farmacología , Compuestos Orgánicos Volátiles/farmacología
7.
Pestic Biochem Physiol ; 178: 104946, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34446184

RESUMEN

Spodoptera litura (Fabricius) is a widely distributed, highly polyphagous pest that can cause severe damage to a variety of economically important crops. Various populations have developed resistance to different classes of insecticides. In this study, we report on two indoxacarb-resistant S. litura populations, namely Ind-R (resistance ratio = 18.37-fold) derived from an indoxacarb-susceptible (Ind-S) population and a population caught from a field (resistance ratio = 46.72-fold). A synergist experiment showed that piperonyl butoxide (PBO) combined with indoxacarb produced higher synergistic effects (synergist ratio = 5.29) in the Ind-R population as compared to Ind-S (synergist ratio = 3.08). Elevated enzyme activity of cytochrome P450 monooxygenases (P450s) was observed for Ind-R (2.15-fold) and the Field-caught population (4.03-fold) as compared to Ind-S, while only minor differences were noticed in the activities of esterases and glutathione S-transferases. Furthermore, expression levels of P450 genes of S. litura were determined by quantitative reverse transcription PCR to explore differences among the three populations. The results showed that the mRNA levels of CYP6AE68, a novel P450 gene belonging to the CYP6 family, were constitutively overexpressed in Ind-R (32.79-fold) and in the Field-caught population (68.11-fold). CYP6AE68 expression in S. litura was further analyzed for different developmental stages and in different tissues. Finally, we report that RNA interference-mediated silencing of CYP6AE68 increased the mortality of fourth-instar larvae exposed to indoxacarb at the LC50 dose level (increase by 33.89%, 29.44% and 22.78% for Ind-S, Ind-R and the Field-caught population, respectively). In conclusion, the findings of this study indicate that expression levels of CYP6AE68 in S. litura larvae are associated with indoxacarb resistance and that CYP6AE68 may play a significant role in detoxification of indoxacarb.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Animales , Sistema Enzimático del Citocromo P-450/genética , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Larva/genética , Oxazinas/farmacología , Spodoptera/genética
8.
Pestic Biochem Physiol ; 162: 6-14, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31836055

RESUMEN

The beet armyworm (Spodoptera exigua) is a highly polyphagous agricultural pest that is distributed worldwide. However, the adaptive mechanisms of S. exigua for various insecticides and defensive substances in host plants are unknown. Insect P450 monooxygenases play an important role in the detoxification of plant toxins and insecticides, leading to insecticides resistance. We investigated the induced effects of xanthotoxin exposure on detoxification enzyme activity and larval tolerance to α-cypermethrin in S. exigua. Our results showed that the lethal concentration (LC50) of α-cypermethrin for xanthotoxin-exposed larvae was 2.1-fold higher than in the control. Moreover, cytochrome P450 enzyme activity was significantly elevated by upregulation of P450 genes in treated larvae. RT-qPCR results showed that CYP9A10 expression level was significantly increased in all treatments, while maximal expression level was observed in xanthotoxin+α-cypermethrin-fed larvae. RNAi-mediated silencing of CYP9A10 further increased mortality by 18%, 26% and 35% at 48 h and by 27%, 43% and 55% at 72 h when larvae were exposed to diets containing chemicals as compared to the control. The results show that CYP9A10 might play an important role in xanthotoxin and α-cypermethrin detoxification in S. exigua. RNAi-mediated silencing could provide an effective synergistic agent for pest control or insecticide resistance management.


Asunto(s)
Insecticidas , Metoxaleno , Animales , Sistema Enzimático del Citocromo P-450 , Larva , Piretrinas , Interferencia de ARN , Spodoptera
9.
Phys Chem Chem Phys ; 21(22): 11731-11739, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31114818

RESUMEN

A novel family of two-dimensional (2D) crystalline metal superhalogens V3X8 (X = F, Cl, Br, I) with intrinsic magnetism was predicted using first-principles calculations in the framework of density functional theory (DFT). The calculation results show that the V3Cl8 monolayer is an intrinsic anti-ferromagnetic semiconductor (AFS) with an indirect bandgap of 0.086 eV at the PBE functional level, while the V3X8 (X = F, Br, I) monolayer exhibits a fascinating ferromagnetic half-metal (FH) property with 100% spin-polarization at the Fermi level. Such 2D materials possess robust dynamical stability as well as thermal stability at room temperature except for V3Br8. In addition, Monte Carlo simulations based on the Ising model with the classical Heisenberg model estimate a Curie temperature of approximately 77 K and 103 K for the V3F8 and V3I8 systems, respectively. Furthermore, we predict an extraordinary phenomenon induced by biaxial compressive strain from the ferromagnetic half-metal (FH) to the ferromagnetic semiconductor (FS) at 2% strain and then to the antiferromagnetic metal (AM) with the biaxial strain increasing up to about 6.3% in the 2D V3I8 monolayer. In the case of 2D V3F8, as the strain varies from -10% to 8%, a series of electronic and magnetic phase transitions of AFS-AM-FH-AFS will occur. These tunable magnetic and electronic properties of 2D halides originate from the competition between AFM direct nearest-neighbor d-d exchange and FM superexchange via halogen p states, which leads to a variety of magnetic states. The explored controllable magnetic properties, electronic properties and the high Curie temperature render the 2D V3I8 monolayer a promising candidate for applications in magnetic logic devices and strain sensor devices.

10.
Int J Mol Sci ; 20(15)2019 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-31390813

RESUMEN

Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductases (CPRs) function as redox partners of cytochrome P450 monooxygenases (P450s). CPRs and P450s in insects have been found to participate in insecticide resistance. However, the CPR of the moth Spodoptera litura has not been well characterized yet. Based on previously obtained transcriptome information, a full-length CPR cDNA of S. litura (SlCPR) was PCR-cloned. The deduced amino acid sequence contains domains and residues predicted to be essential for CPR function. Phylogenetic analysis with insect CPR amino acid sequences showed that SlCPR is closely related to CPRs of Lepidoptera. Quantitative reverse transcriptase PCR (RT-qPCR) was used to determine expression levels of SlCPR in different developmental stages and tissues of S. litura. SlCPR expression was strongest at the sixth-instar larvae stage and fifth-instar larvae showed highest expression in the midgut. Expression of SlCPR in the midgut and fat body was strongly upregulated when fifth-instar larvae were exposed to phoxim at LC15 (4 µg/mL) and LC50 (20 µg/mL) doses. RNA interference (RNAi) mediated silencing of SlCPR increased larval mortality by 34.6% (LC15 dose) and 53.5% (LC50 dose). Our results provide key information on the SlCPR gene and indicate that SlCPR expression levels in S. litura larvae influence their susceptibility to phoxim and possibly other insecticides.


Asunto(s)
Silenciador del Gen , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , NADPH-Ferrihemoproteína Reductasa/genética , Compuestos Organotiofosforados/farmacología , Spodoptera/efectos de los fármacos , Spodoptera/genética , Secuencia de Aminoácidos , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Larva , NADPH-Ferrihemoproteína Reductasa/metabolismo , Filogenia , Interferencia de ARN , Spodoptera/clasificación , Spodoptera/metabolismo
11.
Int J Mol Sci ; 19(3)2018 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-29510578

RESUMEN

In insects, cytochrome P450 monooxygenases (P450s or CYPs) are known to be involved in the detoxification and metabolism of insecticides, leading to increased resistance in insect populations. Spodoptera exigua is a serious polyphagous insect pest worldwide and has developed resistance to various insecticides. In this study, a novel CYP3 clan P450 gene CYP9A105 was identified and characterized from S. exigua. The cDNAs of CYP9A105 encoded 530 amino acid proteins, respectively. Quantitative real-time PCR analyses showed that CYP9A105 was expressed at all developmental stages, with maximal expression observed in fifth instar stage larvae, and in dissected fifth instar larvae the highest transcript levels were found in midguts and fat bodies. The expression of CYP9A105 in midguts was upregulated by treatments with the insecticides α-cypermethrin, deltamethrin and fenvalerate at both LC15 concentrations (0.10, 0.20 and 5.0 mg/L, respectively) and LC50 concentrations (0.25, 0.40 and 10.00 mg/L, respectively). RNA interference (RNAi) mediated silencing of CYP9A105 led to increased mortalities of insecticide-treated 4th instar S. exigua larvae. Our results suggest that CYP9A105 might play an important role in α-cypermethrin, deltamethrin and fenvalerate detoxification in S. exigua.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Proteínas de Insectos/genética , Insecticidas/farmacocinética , Piretrinas/farmacocinética , Spodoptera/genética , Animales , Sistema Enzimático del Citocromo P-450/metabolismo , Inactivación Metabólica , Proteínas de Insectos/metabolismo , Spodoptera/metabolismo
12.
Int J Mol Sci ; 18(11)2017 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-29084173

RESUMEN

Larvae of the polyphagous tobacco cutworm moth, Spodoptera litura (S. litura), encounter potentially toxic allelochemicals in food. It is therefore important for S. litura to produce detoxification enzymes such as cytochrome P450 monooxygenases (P450s). In this study, we have identified two novel cytochrome P450 genes of S. litura, named CYP321A7 and CYP321A9. Phylogenetic analysis indicated that they belong to the CYP321A subfamily. Expression levels of these genes at different development stages were determined by real-time quantitative polymerase chain reaction (PCR). The highest expression was found in the midgut and the fat body. Larvae fed with a diet supplemented with xanthotoxin or coumarin showed a strongly increased expression of CYP321A7 and CYP321A9 in the midgut and fat body as compared to larvae that consumed a control diet. In contrast, larvae consuming a diet containing aflatoxin B1 or quercetin did not induce the expression of these genes. CYP321A7 and CYP321A9 showed different expression profiles with respect to certain allelochemicals. For example, a diet containing cinnamic acid stimulated the expression of CYP321A9, whereas no changes were observed for CYP321A7. We suggest that the fine tuning of P450 gene expression is an important adaptation mechanism that allows polyphagous S. litura larvae to survive in a changing chemical environment.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas de Insectos/genética , Feromonas/farmacología , Spodoptera/efectos de los fármacos , Spodoptera/genética , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Filogenia , Análisis de Secuencia de ADN , Spodoptera/clasificación , Nicotiana/parasitología
13.
Asian-Australas J Anim Sci ; 30(3): 328-337, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27383810

RESUMEN

OBJECTIVE: An experiment was conducted to determine the relationship between the KAP11.1 and the regulation wool fineness. METHODS: In previous work, we constructed a skin cDNA library and isolated a full-length cDNA clone termed KAP11.1. On this basis, we conducted a series of bioinformatics analysis. Tissue distribution of KAP11.1 mRNA was performed using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis. The expression of KAP11.1 mRNA in primary and secondary hair follicles was performed using real-time PCR (real-time polymerase chain reaction) analysis. The expression location of KAP11.1 mRNA in primary and secondary hair follicles was performed using in situ hybridization. RESULTS: Bioinformatics analysis showed that KAP11.1 gene encodes a putative 158 amino acid protein that exhibited a high content of cysteine, serine, threonine, and valine and has a pubertal mammary gland) structural domain. Secondary structure prediction revealed a high proportion of random coils (76.73%). Semi-quantitative RT-PCR showed that KAP11.1 gene was expressed in heart, skin, and liver, but not expressed in spleen, lung and kidney. Real time PCR results showed that the expression of KAP11.1 has a higher expression in catagen than in anagen in the primary hair follicles. However, in the secondary hair follicles, KAP11.1 has a significantly higher expression in anagen than in catagen. Moreover, KAP11.1 gene has a strong expression in inner root sheath, hair matrix, and a lower expression in hair bulb. CONCLUSION: We conclude that KAP11.1 gene may play an important role in regulating the fiber diameter.

14.
Proc Natl Acad Sci U S A ; 110(38): E3631-9, 2013 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-24003150

RESUMEN

Although the function of silicon (Si) in plant physiology has long been debated, its beneficial effects on plant resistance against abiotic and biotic stresses, including insect herbivory, have been well documented. In addition, the jasmonate (JA) signaling pathway plays a crucial role in mediating antiherbivore defense responses in plants. However, potential interactions between JA and Si in response to insect attack have not been examined directly. To explore the role JA may play in Si-enhanced resistance, we silenced the expression of allene oxide synthase (OsAOS; active in JA biosynthesis) and CORONATINE INSENSITIVE1 (OsCOI1; active in JA perception) genes in transgenic rice plants via RNAi and examined resulting changes in Si accumulation and defense responses against caterpillar Cnaphalocrocis medinalis (rice leaffolder, LF) infestation. Si pretreatment increased rice resistance against LF larvae in wild-type plants but not in OsAOS and OsCOI1 RNAi lines. Upon LF attack, wild-type plants subjected to Si pretreatment exhibited enhanced defense responses relative to untreated controls, including higher levels of JA accumulation; increased levels of transcripts encoding defense marker genes; and elevated activities of peroxidase, polyphenol oxidase, and trypsin protease inhibitor. Additionally, reduced Si deposition and Si cell expansion were observed in leaves of OsAOS and OsCOI1 RNAi plants in comparison with wild-type plants, and reduced steady-state transcript levels of the Si transporters OsLsi1, OsLsi2, and OsLsi6 were observed in Si-pretreated plants after LF attack. These results suggest a strong interaction between Si and JA in defense against insect herbivores involving priming of JA-mediated defense responses by Si and the promotion of Si accumulation by JA.


Asunto(s)
Ciclopentanos/metabolismo , Mariposas Nocturnas/fisiología , Oryza/metabolismo , Oxilipinas/metabolismo , Transducción de Señal/fisiología , Silicio/metabolismo , Suelo/análisis , Animales , Catecol Oxidasa/metabolismo , Silenciador del Gen , Proteínas de Choque Térmico/genética , Herbivoria/fisiología , Oxidorreductasas Intramoleculares/genética , Oryza/fisiología , Peroxidasa/metabolismo , Silicio/análisis , Inhibidores de Tripsina/metabolismo
15.
J Chem Ecol ; 41(1): 111-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25547988

RESUMEN

Cytochrome P450 monooxygenases (P450s) of insects are known to be involved in the metabolism or detoxification of plant allelochemicals and insecticides. Spodoptera litura (Lepidoptera, Noctuidae) is a polyphagous moth responsible for severe yield losses in many crops. In this study, two full-length P450 genes, CYP6B48 and CYP6B58, were cloned from S. litura. The cDNA sequences encode proteins with 503 and 504 amino acids, respectively. Phylogenetic analysis revealed that CYP6B48 and CYP6B58 belong to the CYP6B subfamily of P450s. Quantitative real-time PCR analyses showed that CYP6B48 and CYP6B58 were expressed only at larval stage, but not at pupal and adult stages. The highest levels of transcripts were found in the midguts and fat bodies of the larvae. No expression was detected in the ovary or hemolymph. Feeding with diets containing cinnamic acid, quercetin, or coumarin did not affect expression of CYP6B48. In contrast, diet supplemented with xanthotoxin dramatically increased the levels of CYP6B48 transcript in the midgut and fat bodies. Larvae fed with flavone had high levels of transcript of CYP6B48 in the midgut, whereas only slightly elevated levels were found in the fat bodies. Effects of the tested allelochemicals on CYP6B58 expression were minor. Hence, our findings show that S. litura responds to specific allelochemicals such as xanthotoxin with the accumulation of CYP6B48 transcripts, suggesting that specific signals in the food control the insect's ability to convert toxic allelochemicals to less harmful forms at the transcriptional level.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Nicotiana , Feromonas/fisiología , Spodoptera/crecimiento & desarrollo , Spodoptera/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hemolinfa/fisiología , Proteínas de Insectos/genética , Larva/fisiología , Metoxaleno/farmacología , Datos de Secuencia Molecular , Ovario/fisiología , Feromonas/farmacología , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Spodoptera/efectos de los fármacos , Nicotiana/metabolismo
16.
J Plant Res ; 128(5): 763-75, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26045231

RESUMEN

Wedelia trilobata (L.) Hitchc., an ornamental groundcover plant introduced to areas around the world from Central America, has become invasive in many regions. To increase understanding of its geographic distribution and potential extent of spread, two presence-only niche-based modeling approaches (Maxent and GARP) were employed to create models based on occurrence records from its: (1) native range only and (2) full range (native and invasive). Models were then projected globally to identify areas vulnerable to W. trilobata invasion. W. trilobata prefers hot and humid environments and can occur in areas with different environmental conditions than experienced in its native range. Based on native and full occurrence points, GARP and Maxent models produced consistent distributional maps of W. trilobata, although Maxent model results were more conservative. When used to estimate the global invasive distribution of the species, both modeling approaches projected the species to occur in Africa. The GARP full model succeeded in predicting the known occurrences in Australia, while the other models failed to identify favorable habitats in this region. Given the rapid spread of W. trilobata and the serious risk of this species poses to local ecosystems, practical strategies to prevent the establishment and expansion of this species should be sought.


Asunto(s)
Asteraceae/fisiología , Conservación de los Recursos Naturales/métodos , Ecosistema , Especies Introducidas , Modelos Biológicos , Dispersión de las Plantas
17.
Int J Mol Sci ; 16(9): 22606-20, 2015 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-26393579

RESUMEN

Cytochrome P450 monooxygenases (P450s) of insects play crucial roles in the metabolism of endogenous and dietary compounds. Tobacco cutworm moth (Spodoptera litura), an important agricultural pest, causes severe yield losses in many crops. In this study, we identified CYP9A40, a novel P450 gene of S. litura, and investigated its expression profile and potential role in detoxification of plant allelochemicals and insecticides. The cDNA contains an open reading frame encoding 529 amino acid residues. CYP9A40 transcripts were found to be accumulated during various development stages of S. litura and were highest in fifth and sixth instar larvae. CYP9A40 was mainly expressed in the midgut and fat body. Larval consumption of xenobiotics, namely plant allelochemicals (quercetin and cinnamic acid) and insecticides (deltamethrin and methoxyfenozide) induced accumulation of CYP9A40 transcripts in the midgut and fat body. Injection of dsCYP9A40 (silencing of CYP9A40 by RNA interference) significantly increased the susceptibility of S. litura larvae to the tested plant allelochemicals and insecticides. These results indicate that CYP9A40 expression in S. litura is related to consumption of xenobiotics and suggest that CYP9A40 is involved in detoxification of these compounds.


Asunto(s)
Cinamatos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas de Insectos/metabolismo , Insecticidas/metabolismo , Nicotiana/parasitología , Quercetina/metabolismo , Spodoptera/fisiología , Secuencia de Aminoácidos , Animales , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/genética , Regulación de la Expresión Génica , Interacciones Huésped-Parásitos , Inactivación Metabólica , Proteínas de Insectos/química , Proteínas de Insectos/genética , Datos de Secuencia Molecular , Alineación de Secuencia , Spodoptera/química , Spodoptera/genética , Nicotiana/fisiología
18.
Biochem Pharmacol ; 223: 116122, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38467377

RESUMEN

Cutaneous melanoma is the deadliest form of skin cancer, and its incidence is continuing to increase worldwide in the last decades. Traditional therapies for melanoma can easily cause drug resistance, thus the treatment of melanoma remains a challenge. Various studies have focused on reversing the drug resistance. As tumors grow and progress, cancer cells face a constantly changing microenvironment made up of different nutrients, metabolites, and cell types. Multiple studies have shown that metabolic reprogramming of cancer is not static, but a highly dynamic process. There is a growing interest in exploring the relationship between melanoma andmetabolic reprogramming, one of which may belipid metabolism. This review frames the recent research progresses on lipid metabolism in melanoma.In addition, we emphasize the dynamic ability of metabolism during tumorigenesis as a target for improving response to different therapies and for overcoming drug resistance in melanoma.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/metabolismo , Neoplasias Cutáneas/metabolismo , Metabolismo de los Lípidos , Reprogramación Metabólica , Resistencia a Medicamentos , Lípidos , Microambiente Tumoral
19.
20.
Front Plant Sci ; 15: 1367773, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38481397

RESUMEN

Microorganisms are important members of seagrass bed ecosystems and play a crucial role in maintaining the health of seagrasses and the ecological functions of the ecosystem. In this study, we systematically quantified the assembly processes of microbial communities in fragmented seagrass beds and examined their correlation with environmental factors. Concurrently, we explored the relative contributions of species replacement and richness differences to the taxonomic and functional ß-diversity of microbial communities, investigated the potential interrelation between these components, and assessed the explanatory power of environmental factors. The results suggest that stochastic processes dominate community assembly. Taxonomic ß-diversity differences are governed by species replacement, while for functional ß-diversity, the contribution of richness differences slightly outweighs that of replacement processes. A weak but significant correlation (p < 0.05) exists between the two components of ß-diversity in taxonomy and functionality, with almost no observed significant correlation with environmental factors. This implies significant differences in taxonomy, but functional convergence and redundancy within microbial communities. Environmental factors are insufficient to explain the ß-diversity differences. In conclusion, the assembly of microbial communities in fragmented seagrass beds is governed by stochastic processes. The patterns of taxonomic and functional ß-diversity provide new insights and evidence for a better understanding of these stochastic assembly rules. This has important implications for the conservation and management of fragmented seagrass beds.

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