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1.
Plant Biotechnol J ; 16(2): 581-590, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28710782

RESUMEN

The homoterpenes (3E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT) are major herbivore-induced plant volatiles that can attract predatory or parasitic arthropods to protect injured plants from herbivore attack. In this study, DMNT and TMTT were confirmed to be emitted from cotton (Gossypium hirsutum) plants infested with chewing caterpillars or sucking bugs. Two CYP genes (GhCYP82L1 and GhCYP82L2) involved in homoterpene biosynthesis in G. hirsutum were newly identified and characterized. Yeast recombinant expression and enzyme assays indicated that the two GhCYP82Ls are both responsible for the conversion of (E)-nerolidol to DMNT and (E,E)-geranyllinalool to TMTT. The two heterologously expressed proteins without cytochrome P450 reductase fail to convert the substrates to homoterpenes. Quantitative real-time PCR (qPCR) analysis suggested that the two GhCYP82L genes were significantly up-regulated in leaves and stems of G. hirsutum after herbivore attack. Subsequently, electroantennogram recordings showed that electroantennal responses of Microplitis mediator and Peristenus spretus to DMNT and TMTT were both dose dependent. Laboratory behavioural bioassays showed that females of both wasp species responded positively to DMNT and males and females of M. mediator could be attracted by TMTT. The results provide a better understanding of homoterpene biosynthesis in G. hirsutum and of the potential influence of homoterpenes on the behaviour of natural enemies, which lay a foundation to study genetically modified homoterpene biosynthesis and its possible application in agricultural pest control.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Gossypium/metabolismo , Alquenos/metabolismo , Transducción de Señal , Compuestos Orgánicos Volátiles/metabolismo
2.
Plant Cell Environ ; 41(1): 261-274, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29044662

RESUMEN

Herbivore-induced terpenes have been reported to function as ecological signals in plant-insect interactions. Here, we showed that insect-induced cotton volatile blends contained 16 terpenoid compounds with a relatively high level of linalool. The high diversity of terpene production is derived from a large terpene synthase (TPS) gene family. The TPS gene family of Gossypium hirsutum and Gossypium raimondii consist of 46 and 41 members, respectively. Twelve TPS genes (GhTPS4-15) could be isolated, and protein expression in Escherichia coli revealed catalytic activity for eight GhTPS. The upregulation of the majority of these eight genes additionally supports the function of these genes in herbivore-induced volatile biosynthesis. Furthermore, transgenic Nicotiana tabacum plants overexpressing GhTPS12 were generated, which produced relatively large amounts of (3S)-linalool. In choice tests, female adults of Helicoverpa armigera laid fewer eggs on transgenic plants compared with non-transformed controls. Meanwhile, Myzus persicae preferred feeding on wild-type leaves over leaves of transgenic plants. Our findings demonstrate that transcript accumulation of multiple TPS genes is mainly responsible for the production and diversity of herbivore-induced volatile terpenes in cotton. Also, these genes might play roles in plant defence, in particular, direct defence responses against herbivores.


Asunto(s)
Transferasas Alquil y Aril/genética , Gossypium/genética , Gossypium/inmunología , Herbivoria/fisiología , Hidroliasas/metabolismo , Familia de Multigenes , Proteínas de Plantas/metabolismo , Monoterpenos Acíclicos , Transferasas Alquil y Aril/metabolismo , Animales , Áfidos , Cromatografía de Gases y Espectrometría de Masas , Regulación de la Expresión Génica de las Plantas , Gossypium/enzimología , Gossypium/parasitología , Larva , Monoterpenos/metabolismo , Mariposas Nocturnas/fisiología , Filogenia , Plantas Modificadas Genéticamente , Nicotiana/genética , Compuestos Orgánicos Volátiles/metabolismo
3.
Nature ; 487(7407): 362-5, 2012 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-22722864

RESUMEN

Over the past 16 years, vast plantings of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) have helped to control several major insect pests and reduce the need for insecticide sprays. Because broad-spectrum insecticides kill arthropod natural enemies that provide biological control of pests, the decrease in use of insecticide sprays associated with Bt crops could enhance biocontrol services. However, this hypothesis has not been tested in terms of long-term landscape-level impacts. On the basis of data from 1990 to 2010 at 36 sites in six provinces of northern China, we show here a marked increase in abundance of three types of generalist arthropod predators (ladybirds, lacewings and spiders) and a decreased abundance of aphid pests associated with widespread adoption of Bt cotton and reduced insecticide sprays in this crop. We also found evidence that the predators might provide additional biocontrol services spilling over from Bt cotton fields onto neighbouring crops (maize, peanut and soybean). Our work extends results from general studies evaluating ecological effects of Bt crops by demonstrating that such crops can promote biocontrol services in agricultural landscapes.


Asunto(s)
Agricultura , Gossypium , Insecticidas , Control Biológico de Vectores/tendencias , Plantas Modificadas Genéticamente , Agricultura/tendencias , Animales , Áfidos/fisiología , Artrópodos/fisiología , Bacillus thuringiensis/genética , China , Cadena Alimentaria , Gossypium/genética , Gossypium/parasitología , Densidad de Población , Factores de Tiempo
4.
J Chem Ecol ; 43(2): 207-214, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28070757

RESUMEN

Pheromone binding proteins (PBPs) are thought to play key roles in insect sex pheromone recognition; however, there is little in vivo evidence to support this viewpoint in comparison to abundant biochemical data in vitro. In the present study, two noctuid PBP genes HarmPBP1 and HarmPBP2 of the serious agricultural pest, Helicoverpa armigera were selected to be knocked down by RNA interference, and then the changes in electrophysiological and behavioral responses of male mutants to their major sex pheromone component (Z)-11-hexadecenal (Z11-16:Ald) were recorded. There were no significant electrophysiological or behavioral changes of tested male moths in response to Z11-16:Ald when either single PBP gene was knocked down. However, decreased sensitivity of male moths in response to Z11-16:Ald was observed when both HarmPBP1 and HarmPBP2 genes were silenced. These results reveal that both HarmPBP1 and HarmPBP2 are required for the recognition of the main sex pheromone component Z11-16:Ald in H. armigera. Furthermore, these findings may help clarify physiological roles of moth PBPs in the sex pheromone recognition pathway, which in turn could facilitate pest control by exploring sex pheromone blocking agents.


Asunto(s)
Conducta Animal/fisiología , Proteínas de Insectos/metabolismo , Cetonas/farmacología , Mariposas Nocturnas , Interferencia de ARN , Atractivos Sexuales/metabolismo , Animales , Antenas de Artrópodos/efectos de los fármacos , Antenas de Artrópodos/fisiología , Conducta Animal/efectos de los fármacos , Fenómenos Electrofisiológicos , Técnicas de Silenciamiento del Gen , Control de Insectos , Proteínas de Insectos/genética , Cetonas/metabolismo , Masculino , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Mariposas Nocturnas/fisiología , Unión Proteica , Atractivos Sexuales/genética , Conducta Sexual Animal/efectos de los fármacos
5.
Artículo en Inglés | MEDLINE | ID: mdl-28321909

RESUMEN

Insects rely heavily on their sophisticated chemosensory systems to locate host plants and find conspecific mates. Although the molecular mechanisms of odorant recognition in many Lepidoptera species have been well explored, limited information has been reported on the geometrid moth Ectropis obliqua Prout, an economically important pest of tea plants. In the current study, we first attempted to identify and characterize the putative olfactory carrier proteins, including odorant-binding proteins (OBPs) and chemosensory proteins (CSPs). By analyzing previously obtained transcriptomic data of third-instar larvae, five OBPs and 14 CSPs in E. obliqua were identified. Sequence alignment, conserved motif identification, and phylogenetic analysis suggested that candidate proteins have typical characteristics of the insect OBP or CSP family. The expression patterns regarding life stages and different tissues were determined by quantitative real-time PCR. The results revealed that four transcripts (OBP2, OBP4 and CSP8, CSP10) had larvae preferential expression profiles and nine candidate genes (PBP1, OBP1 and CSP2, CSP4, CSP5, CSP6, CSP7, CSP11, and CSP13) were adult-biased expressed. Further specific tissue expression profile evaluation showed that OBP1, OBP2, OBP4, and PBP1 were highly expressed at olfactory organs, implying their potential involvement in chemical cue detection, whereas CSPs were ubiquitously detected among all of the tested tissues and could be associated with multiple physiological functions. This study provided a foundation for understanding the physiological functions of OBPs and CSPs in E. obliqua and will help pave the way for the development of a new environmental friendly pest management strategy against the tea geometrid moth.


Asunto(s)
Proteínas de Insectos/genética , Mariposas Nocturnas/genética , Receptores Odorantes/genética , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Proteínas de Insectos/química , Larva , Masculino , Filogenia , Receptores Odorantes/química , Alineación de Secuencia , Olfato , Transcriptoma
6.
Mol Cell Proteomics ; 12(5): 1170-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23345539

RESUMEN

There is a critical need to identify biomarkers for Systemic Lupus Erythematosus (SLE) which has a high prevalence of renal failure. When urine from patients with lupus nephritis was recently screened for the levels of ∼280 molecules using an exploratory array-based proteomic platform, elevated angiostatin levels were noted. Angiostatin is a bioactive fragment of plasminogen, and has been known to have modulatory function in angiogenesis and inflammation. The significant elevation in urinary angiostatin was next validated in an independent cohort of SLE patients (n = 100) using ELISA. Among patients with SLE, urine angiostatin was significantly increased in active SLE compared with inactive SLE, correlating well with the SLEDAI disease activity index and SLICC renal activity score (r = 0.66, p < 0.0001). ROC curve analysis further confirmed that urinary angiostatin had the capacity to discriminate patients with active SLE from those with inactive disease. Patients with Class IV lupus nephritis exhibited the highest levels of urinary angiostatin. Immunohistochemistry staining localized angiostatin expression to the renal tubular cells in these patients. Finally, when paired urine-kidney samples procured concurrently from patients with LN were next examined, urine angiostatin levels correlated strongly with the renal pathology chronicity index, but not with the activity index. Given that Class IV lupus nephritis and renal pathology chronicity changes forebode poor renal and patient survival, urinary angiostatin emerges as a novel noninvasive marker of renal disease in SLE. Longitudinal studies are in progress to further assess the disease-predictive potential of urinary angiostatin.


Asunto(s)
Angiotensinas/orina , Riñón/patología , Nefritis Lúpica/orina , Adulto , Biomarcadores/orina , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Humanos , Masculino , Análisis por Matrices de Proteínas , Índice de Severidad de la Enfermedad
7.
J Chem Ecol ; 40(6): 541-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24928754

RESUMEN

Odorant binding proteins (OBPs) are believed to be important for transporting semiochemicals through the aqueous sensillar lymph to the olfactory receptor cells within the insect antennal sensilla. In this study, three new putative OBP genes, MmedOBP8-10, were identified from a Microplitis mediator (Hymenoptera: Braconidae) antennal cDNA library. Quantitative real-time PCR (qRT-PCR) analysis revealed that all three of the OBP genes were expressed mainly in the antennae of adult wasps. The three OBPs were recombinantly expressed in Escherichia coli and purified by Ni ion affinity chromatography. Fluorescence competitive binding assays were performed using N-phenyl-naphthylamine as a fluorescent probe and 45 small organic compounds as competitors. These assays demonstrated that the three M. mediator OBPs can bind a broad range of odorant molecules with different binding affinities. They can bind the following ligands: nonane, farnesol, nerolidol, nonanal, ß-ionone, acetic ether, and farnesene. In a Y-tube assay with these ligands as odor stimuli and paraffin oil as a control, all ligands, except nerolidol and acetic ether, were able to elicit behavioral responses in adult M. mediator. The wasps were significantly attracted to ß-ionone, nonanal, and farnesene and repelled by nonane and farnesol. The results of this work provide insight into the chemosensory functions of the OBPs in M. mediator.


Asunto(s)
Himenópteros , Proteínas de Insectos/metabolismo , Receptores Odorantes/metabolismo , 1-Naftilamina/análogos & derivados , 1-Naftilamina/metabolismo , Aldehídos , Animales , Antenas de Artrópodos , Conducta Animal , Femenino , Colorantes Fluorescentes/metabolismo , Regulación de la Expresión Génica , Himenópteros/genética , Proteínas de Insectos/genética , Masculino , Datos de Secuencia Molecular , Norisoprenoides , Receptores Odorantes/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
8.
J Biomater Appl ; 38(8): 890-904, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38282509

RESUMEN

Poly (acrylic acid) (PAA), an anionic polymer was used to prepare ion pair self-assembly (IPSAM) with 4-(methylthio)aniline (MTA), a hydrophobic counter ion, which is responsive to temperature and oxidation. The IPSAM was formed when the carboxylic to amino group molar ratio was 7/3-5/5. The structure of the IPSAM nanoparticle was spherical whose diameter was 30-40 nm on the TEM images. The PAA/MTA ion pair showed the upper critical solution temperature (UCST) that hiked with increasing MTA content. When the MTA of the ion pair was oxidized by H2O2, the UCST was also increased. The amphiphilic property of the ion pair was responsible for interface activity which declined upon the oxidation of the MTA. The surface tension was low for the ratio of PAA/MTA (5/5), which made the 5/5 ratio suitable for further studies. The interaction between PAA and MTA, which was ionic, and the oxidation of MTA was confirmed by FT-IR spectroscopy. The release of payload (i.e. Nile red) in IPSAM was restrained below the UCST but it was triggered above the phase transition temperature possibly due to the disintegration of the IPSAM whereas on MTA oxidation the release was shielded due to more hydrophobicity. The release was found to be higher in tumor environment temperature which could be controlled with the input concentration of H2O2 giving a stable IPSAM. The cell viability results showed that IPSAM has no significant cytotoxicity and can serve as a drug carrier for stimulus-response.


Asunto(s)
Peróxido de Hidrógeno , Polímeros , Espectroscopía Infrarroja por Transformada de Fourier , Polímeros/química , Micelas , Portadores de Fármacos , Concentración de Iones de Hidrógeno
9.
Eur J Cancer Prev ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38870068

RESUMEN

PURPOSE: The microcystic, elongated, and fragmented (MELF) pattern, characterized by myxoid and inflamed stroma, is readily identifiable as a form of myometrial infiltration. This meta-analysis endeavors to assess the prognostic significance of MELF infiltration patterns in patients diagnosed with endometrial cancer. METHODS: A comprehensive literature search, spanning until 11 October 2023, across PubMed, Embase, Cochrane, and Web of Science databases, identified 23 relevant studies involving 5199 patients. Data analysis was performed using Stata 16.0. RESULTS: Analysis indicates that MELF infiltration predicts a higher risk of lymph node metastasis in endometrial cancer patients [hazard ratios (HR) = 5.05; 95% confidence interval (CI), 3.62-7.05; P < 0.05]. Notably, this association remains consistent across various patient demographics, analytical approaches, study designs, and treatment modalities. However, MELF infiltration does not significantly correlate with recurrence (HR = 1.05; 95% CI, 0.73-1.52; P > 0.05), overall survival (HR = 1.24; 95% CI, 0.91-1.68; P > 0.05), or disease-free survival (HR = 1.40; 95% CI, 0.85-2.28; P > 0.05). CONCLUSION: While MELF infiltration heightens the risk of lymph node metastasis in endometrial cancer, its impact on recurrence, overall survival, and disease-free survival remains statistically insignificant.

10.
BMC Genomics ; 14: 636, 2013 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-24053512

RESUMEN

BACKGROUND: One of the challenges in insect chemical ecology is to understand how insect pheromones are synthesised, detected and degraded. Genome wide survey by comparative sequencing and gene specific expression profiling provide rich resources for this challenge. A. ipsilon is a destructive pest of many crops and further characterization of the genes involved in pheromone biosynthesis and transport could offer potential targets for disruption of their chemical communication and for crop protection. RESULTS: Here we report 454 next-generation sequencing of the A. ipsilon pheromone gland transcriptome, identification and expression profiling of genes putatively involved in pheromone production, transport and degradation. A total of 23473 unigenes were obtained from the transcriptome analysis, 86% of which were A. ipsilon specific. 42 transcripts encoded enzymes putatively involved in pheromone biosynthesis, of which 15 were specifically, or mainly, expressed in the pheromone glands at 5 to 120-fold higher levels than in the body. Two transcripts encoding for a fatty acid synthase and a desaturase were highly abundant in the transcriptome and expressed more than 40-fold higher in the glands than in the body. The transcripts encoding for 2 acetyl-CoA carboxylases, 1 fatty acid synthase, 2 desaturases, 3 acyl-CoA reductases, 2 alcohol oxidases, 2 aldehyde reductases and 3 acetyltransferases were expressed at a significantly higher level in the pheromone glands than in the body. 17 esterase transcripts were not gland-specific and 7 of these were expressed highly in the antennae. Seven transcripts encoding odorant binding proteins (OBPs) and 8 encoding chemosensory proteins (CSPs) were identified. Two CSP transcripts (AipsCSP2, AipsCSP8) were highly abundant in the pheromone gland transcriptome and this was confirmed by qRT-PCR. One OBP (AipsOBP6) were pheromone gland-enriched and three OBPs (AipsOBP1, AipsOBP2 and AipsOBP4) were antennal-enriched. Based on these studies we proposed possible A. ipsilon biosynthesis pathways for major and minor sex pheromone components. CONCLUSIONS: Our study identified genes potentially involved in sex pheromone biosynthesis and transport in A. ipsilon. The identified genes are likely to play essential roles in sex pheromone production, transport and degradation and could serve as targets to interfere with pheromone release. The identification of highly expressed CSPs and OBPs in the pheromone gland suggests that they may play a role in the binding, transport and release of sex pheromones during sex pheromone production in A. ipsilon and other Lepidoptera insects.


Asunto(s)
Proteínas de Insectos/genética , Mariposas Nocturnas/genética , Atractivos Sexuales/biosíntesis , Transcriptoma , Animales , Etiquetas de Secuencia Expresada , Femenino , Perfilación de la Expresión Génica , Biblioteca de Genes , Masculino , Redes y Vías Metabólicas/genética , Análisis de Secuencia de ADN , Atractivos Sexuales/genética
11.
J Chem Ecol ; 39(9): 1221-31, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23955060

RESUMEN

Semiochemicals such as sex pheromones and plant volatiles are crucial components of insect mating systems and host plant localization. In the olfactory signal transduction pathway, odorant-binding proteins (OBPs) are important elements that function in the first step of the pathway by carrying hydrophobic semiochemicals across the sensillum lymph to the olfactory receptors (ORs). In this study, we examined the binding affinities of semiochemicals to AlinOBP10, a putative OBP from the alfalfa plant bug, Adelphocoris lineolatus, that we demonstrate is expressed mainly in sensory organs. We then characterized the biological activities of the high affinity semiochemicals by measuring their electrophysiological activities in antennae and behavioral responses in the plant bug. AlinOBP10 displayed weak binding affinities to two major putative pheromone components, hexyl butyrate and (E)-2-hexenyl butyrate. In contrast, AlinOBP10 exhibited higher binding affinities to six host plant volatiles, namely myrcene, ß-pinene, ß-ionone, 3-hexanone, (E)-2-hexenal, and 1-hexanol. The biological activities of these six putative ligands were further studied in electroantennogram recordings and Y-tube olfactometer trials. The three compounds, (E)-2-hexenal, 1-hexanol, and 3-hexanone elicited strong electrophysiological responses, but elicited distinct behaviors. While 3-hexanone was attractive to female adults, (E)-2-hexenal and 1-hexanol were significant repellents. Although a weak electrophysiological response was elicited with ß-pinene, it was a strong repellent. These results demonstrate that AlinOBP10 can interact with attractants, as well as repellents, with some specificity toward plant volatiles over sex pheromones.


Asunto(s)
Heterópteros/fisiología , Feromonas/metabolismo , Receptores Odorantes/metabolismo , Animales , Antenas de Artrópodos/metabolismo , Conducta Animal/fisiología , Femenino , Masculino , Proteínas Recombinantes/metabolismo , Compuestos Orgánicos Volátiles/metabolismo
12.
Front Pharmacol ; 14: 1183514, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37426807

RESUMEN

Background: Clinical trials have shown that the use of trastuzumab deruxtecan (DS-8201) alone is expected to provide novel therapeutic options for HER2-low/positive patients. Nevertheless, there are some variations in the efficacy of trial results, with potential risks at the safety level. Most DS-8201 trials in HER2 advanced breast cancer (ABC) have been conducted in the form of small-sample nonrandomized controlled studies, resulting in a lack of validated indicators to evaluate the efficacy and safety of DS-8201. Thus, this meta-analysis aimed to pool the results of various trials of DS-8201 alone to explore the efficacy and safety of DS-8201 in patients with HER2-low/positive advanced breast cancer. Methods: Relevant studies were searched in seven databases, including Embase, PubMed, Web of Science, Cochrane Library, CNKI, VIP database and WanFang data, to collect single-arm studies on DS-8201 for HER2-low/positive ABC. MINORS was adopted for quality assessment and STATA 16.0 for data analysis. Results: Ten studies involving 1,108 patients were included in this meta-analysis. As for the tumor response rate, the pooled ORR and DCR of all studies reached 57% (95% CI: 47%-67%) and 92% (95% CI: 89%-96%) respectively, and the pooled ORRs of the HER2-low expression group and the HER2-positive expression group were 46% (95% CI: 35%-56%) and 64% (95% CI: 54%-74%). Only the low expression group achieved median survival time, with a pooled median PFS and median OS of 9.24 (95% CI: 7.54-10.94) months and 23.87 (95% CI: 21.56-26.17) months, respectively. The most common treatment-related adverse events from DS-8201 were nausea (all grades: 62%; ≥ grade III: 5%), fatigue (all grade: 44%; ≥ grade III: 6%), and alopecia (all grades: 38%; ≥ grade III: 0.5%). Drug-related interstitial lung disease or pneumonitis occurred in 13% of the 1,108 patients, with only a 1% incidence of AE ≥ grade III. Conclusion: The present study suggests that DS-8201 is effective and safe in the treatment of ABC with low or positive HER2 expression, providing additional relevant information for its clinical application. However, further strengthening of the pairs is needed, as well as more clinical studies to support individualized treatment. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023390316.

13.
Transgenic Res ; 21(2): 279-91, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21688166

RESUMEN

In this study, the non-target effects of Bt rice "KMD2" expressing a Cry1Ab protein on the performance of the brown planthopper (BPH), Nilaparvata lugens, over multiple generations were evaluated under laboratory and field conditions. In the laboratory, BPH was reared to observe the impact of the Bt rice as compared to its parental non-Bt cultivar Xiushui 11, while the population dynamics and oviposition performance of BPH were investigated in the field. The survival of BPH nymphs fed Bt and non-Bt rice did not differ significantly. The nymph developmental duration of BPH was significantly delayed by the Bt rice by comparison with the non-Bt rice for the 1st and 2nd but not the 4th generation. Most importantly, the fecundity of BPH on the Bt rice was significantly decreased in every generation when compared with the non-Bt rice. In the field investigations, the population density of BPH nymphs was significantly lower in the Bt rice field. However, the temporal pattern of population dynamics of BPH adults was similar between the Bt and non-Bt rice, presumably due to migratory interference of the adults. In the Bt rice field, the percentage of tillers with eggs and the number of eggs per tiller were also significantly lower from tillering to mature stage. Additionally, Cry1Ab protein could not be detected in guts from single BPH adults. In general, our results suggest that the Bt rice "KMD2" could not stimulate an outbreak of BPH.


Asunto(s)
Proteínas Bacterianas/genética , Endotoxinas/genética , Regulación de la Expresión Génica de las Plantas , Genes Sintéticos , Hemípteros/patogenicidad , Proteínas Hemolisinas/genética , Oryza/parasitología , Migración Animal , Animales , Toxinas de Bacillus thuringiensis , Femenino , Fertilidad , Hemípteros/crecimiento & desarrollo , Hemípteros/fisiología , Herbivoria/fisiología , Longevidad , Masculino , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Oryza/genética , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Oviposición , Recuento de Huevos de Parásitos , Control Biológico de Vectores/métodos , Enfermedades de las Plantas/parasitología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo , Plantas Modificadas Genéticamente/parasitología , Densidad de Población , Dinámica Poblacional , Análisis de Supervivencia
14.
J Chem Ecol ; 38(3): 287-94, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22402893

RESUMEN

Odorant receptors are thought to play critical roles in the perception of chemosensory stimuli by insects. The primary method to address the functions of odorant receptors in insects is to use in vitro binding assays between the receptors and potential chemical stimuli. We injected MmedOrco dsRNA into the abdominal cavity of a braconid wasp, Microplitis mediator, and assayed for expression of this gene 72 h after treatment (RNAi). Quantitative real-time PCR demonstrated that the level of mRNA expression in MmedOrco dsRNA-treated M. mediator was significantly reduced (>90%) when compared with water-treated controls. Furthermore, electroantennogram (EAG) responses of M. mediator to two chemical attractants, nonanal and farnesene, were also reduced significantly (~70%) in RNAi-treated M. mediator when compared to controls. RNAi-treated M. mediator also responded by walking/flying at a lower rate to both chemicals when compared with controls in a Y-tube olfactometer bioassay, which provides direct evidence that MmedOrco plays an important role in perception of nonanal and farnesene in M. mediator.


Asunto(s)
Proteínas de Insectos/metabolismo , Feromonas/metabolismo , Receptores Odorantes/metabolismo , Avispas/fisiología , Aldehídos/metabolismo , Animales , Conducta Animal , Fenómenos Electrofisiológicos , Femenino , Vuelo Animal , Proteínas de Insectos/genética , Masculino , Interferencia de ARN , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Odorantes/genética , Sesquiterpenos/metabolismo , Caminata , Avispas/genética , Avispas/metabolismo
15.
Biochem Biophys Res Commun ; 407(2): 393-9, 2011 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-21396914

RESUMEN

Two high-quality cDNA libraries were constructed from female and male antennae of the cotton bollworm Helicoverpa armigera (Hübner). The titers were approximately 2.0 × 106 pfu/ml for females and 2.3 × 106 pfu/ml for males, and this complies with the test requirement. From the libraries, 1750 male ESTs and 1640 female ESTs were sequenced and further analyzed. We identified 15 olfactory genes (12 are new), and 14 of them have the characteristic six conserved cysteine residues. With the exception of OBP9, all the genes were classified as classical OBP genes. By alignment and cluster analysis, the 14 classical OBPs were divided into pheromone binding protein (PBP) genes, odorant binding protein (OBP) genes, general odorant binding protein 1 (GOBP1) genes, general odorant binding protein 2 (GOBP2) genes and antennae binding protein (ABP) genes. Among these genes, we obtained three PBP genes (PBP1-PBP3) including two new PBP genes, one new ABP gene, nine new OBP genes (OBP1-OBP9), one known GOBP1 gene and one known GOBP2 gene. Furthermore, the expression patterns of these 14 classical OBP genes were investigated in various tissues by real-time quantitative polymerase chain reaction (qPCR). The results indicated that some OBP genes are expressed differently in different sexes and tissues, but most of them are highly expressed in antennae.


Asunto(s)
Expresión Génica , Biblioteca de Genes , Lepidópteros/genética , Receptores Odorantes/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , Etiquetas de Secuencia Expresada , Femenino , Masculino , Datos de Secuencia Molecular , Filogenia , Receptores Odorantes/clasificación
16.
J Chem Ecol ; 37(2): 189-94, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21184151

RESUMEN

Chemoreception in insects is mediated by small odorant-binding proteins (OBPs) that are believed to carry lipophilic stimuli to the olfactory receptor cells through the aqueous sensillar lymph. Binding experiments and recent structural studies of OBPs have illustrated their versatility and ability to accommodate ligands of different shapes and chemical structures. We expressed and purified seven recombinant OBPs (MmedOBP1-MmedOBP7) from the parasitic wasp, Microplitis mediator (Hymenoptera: Braconidae) in a prokaryotic expression system. With 4,4'-dianilino-1,1'-binaphthyl-5,5'-sulfonic acid (bis-ANS) as a fluorescent probe, the ligand-binding specificities of these seven MmedOBPs with 50 small organic compounds were investigated in vitro. The results revealed that all of the M. mediator OBPs can bind a wide variety of odorant molecules with different binding affinities. The best ligand for all seven MmedOBPs was ß-ionone. MmedOBP2 showed affinity for some aromatic compounds, whereas MmedOBP4 and MmedOBP6 bound several terpenoids. MmedOBP5 bound ß-ionone, but did not bind any of the other potential ligands that we tested.


Asunto(s)
Himenópteros , Proteínas de Insectos/metabolismo , Receptores Odorantes/metabolismo , Proteínas Recombinantes/metabolismo , Naftalenosulfonatos de Anilina/química , Naftalenosulfonatos de Anilina/metabolismo , Animales , Femenino , Colorantes Fluorescentes/química , Colorantes Fluorescentes/metabolismo , Masculino , Plantas/química , Unión Proteica , Especificidad por Sustrato , Compuestos Orgánicos Volátiles/metabolismo
17.
Arch Insect Biochem Physiol ; 77(2): 81-99, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21541988

RESUMEN

In the insect phylum, the relationships between individuals and their environment are often modulated by chemical communication. Odorant binding proteins (OBPs) are widely and robustly expressed in insect olfactory organs and play a key role in chemosensing and transporting hydrophobic odorants across the sensillum lymph to the olfactory receptor neuron. In this study, a novel OBP gene (AlinOBP1) in the lucerne plant bug, Adelphocoris lineolatus was identified, cloned and expressed. Real-time PCR results indicated that the expression level of AlinOBP1 gene differed in each developmental stage (from first instar to adult) and was predominantly expressed in the antennae of adults. The expression level of AlinOBP1 was 1.91 times higher in male antennae than in female antennae. The binding properties of AlinOBP1 with 114 odorants were measured using a fluorescence probe, N-phenyl-1-naphthylamine (1-NPN), with fluorescence competitive binding. The results revealed that AlinOBP1 exhibits high binding abilities with two major putative pheromone components, ethyl butyrate and trans-2-hexenyl butyrate. In addition, it was observed that six volatiles released from cotton, octanal, nonanal, decanal, 2-ethyl-1-hexanol, ß-caryophyllene and ß-ionone also bind to AlinOBP1. Immunocytochemistry analysis showed that AlinOBP1 was expressed in the sensillum lymph of sensilla trichodica and sensilla basiconca. Our results demonstrate that AlinOBP1 may function as a carrier in the chemoperception of the lucerne plant bug.


Asunto(s)
Heterópteros/genética , Receptores Odorantes/genética , Secuencia de Aminoácidos , Animales , Antenas de Artrópodos/metabolismo , Clonación Molecular , Femenino , Regulación del Desarrollo de la Expresión Génica , Heterópteros/crecimiento & desarrollo , Heterópteros/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/aislamiento & purificación , Proteínas de Insectos/metabolismo , Masculino , Datos de Secuencia Molecular , Feromonas/metabolismo , Reacción en Cadena de la Polimerasa , Receptores Odorantes/análisis , Receptores Odorantes/aislamiento & purificación , Receptores Odorantes/metabolismo , Sensilos/metabolismo , Caracteres Sexuales
18.
Insects ; 12(5)2021 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-34066819

RESUMEN

OBPs play a crucial role in the recognition of ligands and are involved in the initial steps of semiochemical perception. The diverse expression of OBP genes allows them to participate in different physiological functions in insects. In contrast to classic OBPs with typical olfactory roles in A. lineolatus, the physiological functions of Plus-C OBPs remain largely unknown. In addition, detection of the expression of insect OBP genes by conventional methods is difficult in vitro. Here, we focused on AlinOBP14, a Plus-C OBP from A. lineolatus, and we developed a PNA-GO-based mRNA biosensor to detect the expression of AlinOBP14. The results demonstrated that AlinOBP14 plays dual roles in A. lineolatus. The AlinOBP14 is expressed beneath the epidermis of the vertex and gena in heads of A. lineolatus, and it functions as a carrier for three terpenoids, while AlinOBP14 is also expressed in the peripheral antennal lobe and functions as a carrier for endogenous compounds such as precursors for juvenile hormone (JH) and JHⅢ. Our investigation provides a new method to detect the expression of OBP genes in insects, and the technique will facilitate the use of these genes as potential targets for novel insect behavioral regulation strategies against the pest.

19.
Arch Insect Biochem Physiol ; 73(2): 61-73, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19847794

RESUMEN

Aminopeptidase N (APN) and cadherin-like proteins have been previously identified as Cry1Ac-binding proteins in Helicoverpa armigera (Hübner). In this study, a proteomic approach was used to identify novel Cry1Ac-binding proteins in H. armigera. Brush border membrane vesicles (BBMV) of H. armigera were extracted and separated by two-dimensional gel electrophoresis (2-DE). Cry1Ac-binding proteins were detected using antisera against Cry1Ac. Peptide mass fingerprinting (PMF) was used to identify Cry1Ac-binding proteins. In total, four proteins were identified as candidate Cry1Ac-binding proteins in H. armigera: vacuolar ATP synthase (V-ATPase) subunit B, actin, heat shock cognate protein (HSCP), and a novel protein.


Asunto(s)
Proteínas Bacterianas/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Proteínas de Insectos/metabolismo , Mariposas Nocturnas , Animales , Toxinas de Bacillus thuringiensis , Vesículas Citoplasmáticas/química , Vesículas Citoplasmáticas/metabolismo , Tracto Gastrointestinal/química , Tracto Gastrointestinal/ultraestructura , Microvellosidades/química , Microvellosidades/metabolismo , Unión Proteica , Proteómica
20.
J Econ Entomol ; 103(4): 1444-53, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20857760

RESUMEN

Six transgenic rice, Oryza sativa L., lines (G6H1, G6H2, G6H3, G6H4, G6H5, and G6H6) expressing a fused Cry1Ab/Vip3H protein, were evaluated for resistance against the Asiatic rice borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae), and the stem borer Sesamia inferens (Walker) (Lepidoptera: Noctuidae) in the laboratory and field. The bioassay results indicated that the mortality of Asiatic rice borer and S. inferens neonate larvae on six transgenic lines from seedling to filling stage was up to 100% at 168 h after infestation. The cumulative feeding area by Asiatic rice borer neonate larvae on all transgenic lines was significantly reduced compared with the untransformed parental 'Xiushui 110' rice. A 2-yr field evaluation showed that damage during the vegetative stage (deadheart) or during the reproductive stage (whitehead) caused by Asiatic rice borer and S. inferens for transgenic lines was much lower than the control. For three lines (G6H1, G6H2, and G6H6), no damage was found during the entire growing period. Estimation of fused Cry1Ab/Vip3H protein concentrations using PathoScreen kit for Bt-Cry1Ab/1Ac protein indicated that the expression levels of Cry1Ab protein both in main stems (within the average range of 0.006-0.073% of total soluble protein) and their flag leaves (within the average range of 0.001-0.038% of total soluble protein) were significantly different among six transgenic lines at different developmental stages. Both laboratory and field researches suggested that the transgenic rice lines have considerable potential for protecting rice from attack by both stem borers.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Endotoxinas/genética , Endotoxinas/farmacología , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacología , Mariposas Nocturnas/efectos de los fármacos , Oryza/genética , Oryza/metabolismo , Animales , Toxinas de Bacillus thuringiensis , Oryza/parasitología , Plantas Modificadas Genéticamente
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