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排序方式: 共有1320条查询结果,搜索用时 30 毫秒
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Spliceosome-targeted therapies trigger an antiviral immune response in triple-negative breast cancer
Elizabeth A. Bowling Jarey H. Wang Fade Gong William Wu Nicholas J. Neill Ik Sun Kim Siddhartha Tyagi Mayra Orellana Sarah J. Kurley Rocio Dominguez-Vidaña Hsiang-Ching Chung Tiffany Y.-T. Hsu Julien Dubrulle Alexander B. Saltzman Heyuan Li Jitendra K. Meena Gino M. Canlas Srinivas Chamakuri Thomas F. Westbrook 《Cell》2021,184(2):384-403.e21
3.
Meena Rajesh Kumar Reddy Kanubothula Sitarami Gautam Ranjana Maddela Surender Reddy Attipalli Ramachandra Gudipalli Padmaja 《Photosynthesis research》2021,147(3):253-267
Photosynthesis Research - Heterosis is a phenomenon wherein F1 hybrid often displays phenotypic superiority and surpasses its parents in terms of growth and agronomic traits. Investigations on the... 相似文献
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Don Trinh Nguyen Jens Christian G?pfert Nobuhiro Ikezawa Gillian MacNevin Meena Kathiresan Jürgen Conrad Otmar Spring Dae-Kyun Ro 《The Journal of biological chemistry》2010,285(22):16588-16598
Sesquiterpene lactones are characteristic natural products in Asteraceae, which constitutes ∼8% of all plant species. Despite their physiological and pharmaceutical importance, the biochemistry and evolution of sesquiterpene lactones remain unexplored. Here we show that germacrene A oxidase (GAO), evolutionarily conserved in all major subfamilies of Asteraceae, catalyzes three consecutive oxidations of germacrene A to yield germacrene A acid. Furthermore, it is also capable of oxidizing non-natural substrate amorphadiene. Co-expression of lettuce GAO with germacrene synthase in engineered yeast synthesized aberrant products, costic acids and ilicic acid, in an acidic condition. However, cultivation in a neutral condition allowed the de novo synthesis of a single novel compound that was identified as germacrene A acid by gas and liquid chromatography and NMR analyses. To trace the evolutionary lineage of GAO in Asteraceae, homologous genes were further isolated from the representative species of three major subfamilies of Asteraceae (sunflower, chicory, and costus from Asteroideae, Cichorioideae, and Carduoideae, respectively) and also from the phylogenetically basal species, Barnadesia spinosa, from Barnadesioideae. The recombinant GAOs from these genes clearly showed germacrene A oxidase activities, suggesting that GAO activity is widely conserved in Asteraceae including the basal lineage. All GAOs could catalyze the three-step oxidation of non-natural substrate amorphadiene to artemisinic acid, whereas amorphadiene oxidase diverged from GAO displayed negligible activity for germacrene A oxidation. The observed amorphadiene oxidase activity in GAOs suggests that the catalytic plasticity is embedded in ancestral GAO enzymes that may contribute to the chemical and catalytic diversity in nature. 相似文献
5.
Bhuvnesh Shrivastava Shilpi Thakur Yogender Pal Khasa Akshaya Gupte Anil Kumar Puniya Ramesh Chander Kuhad 《Biodegradation》2011,22(4):823-831
In order to improve the digestibility and nutrient availability in rumen, wheat straw was subjected to solid state fermentation
(SSF) with white-rot fungi (i.e. Pleurotus ostreatus and Trametes versicolor) and the fermented biomass (called myco-straw) was evaluated for biochemical, enzymatic and nutritional parameters. The fungal
treatment after 30 days led to significant decrease (P < 0.05) in cell wall constituents viz, acid detergent fiber (ADF), neutral detergent fiber (NDF), hemicellulose, lignin and
cellulose to the extent of 35.00, 38.88, 45.00, 37.48 and 37.86%, respectively in P. ostreatus fermented straw, while 30.04, 33.85, 39.90, 31.29 and 34.00%, respectively in T. versicolor fermented straw. However, maximum efficiency of fermentation in terms of low carbohydrate consumption per unit of lignin
degradation, favoring cattle feed production was observed for P. ostreatus on the 10th day (17.12%) as compared with T. versicolor on the 30th day (16.91%). The myco-straw was found to contain significantly high (P < 0.05) crude protein (CP; 4.77% T. versicolor, 5.08% P. ostreatus) as compared to control straw (3.37%). Metabolizable energy (ME, MJ/kg DM), percent organic matter digestibility (OMD) and
short chain fatty acids (SCFAs; mmol) production also increased considerably from control straw (4.40, 29.91 and 0.292) to
a maximum up to P. ostreatus fermented straw (4.92, 33.39 and 0.376 on 20th day) and T. versicolor fermented straw (4.66, 31.74 and 0.334 on 10th day), respectively. Moreover, the myco-straw had lower organic carbon and
was rich in nitrogen with lower C/N ratio as compared to control wheat straw. Results suggest that the fungal fermentation
of wheat straw effectively improved CP content, OM digestibility, SCFAs production, ME value and simultaneously lowered the
C/N ratio, thus showing potential for bioconversion of lignin rich wheat straw into high energy cattle feed. 相似文献
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In Ayurveda, Withania somnifera is commonly known as Ashwagandha, its roots are specifically used in medicinal and clinical applications. It possesses numerous therapeutic actions which include anti-inflammatory, sedative, hypnotic and narcotic. Extracts from this plant have been reported for its anticancer properties. In this study we evaluated for the first time, the cytotoxic effect of Withania root extract on human malignant melanoma A375 cells. The crude extract of Withania was tested for cytotoxicity against A375 cells by MTT assay. Cell morphology of treated A375 cells was visualized through phase contrast as well as fluorescence microscopy. Agarose gel electrophoresis was used to check DNA fragmentation of the crude extract treated cells. Crude extract of Withania root has the potency to reduce viable cell count in dose as well as time dependent manner. Morphological change of the A375 cells was also observed in treated groups in comparison to untreated or vehicle treated control. Apoptotic body and nuclear blebbing were observed in DAPI stained treated cells under fluorescence microscope. A ladder of fragmented DNA was noticed in treated cells. Thus it might be said that the crude water extract of Withania somnifera has potent cytotoxic effect on human malignant melanoma A375 cells. 相似文献
9.
Ravinder Raju Bernard F. Castillo Stewart K. Richardson Meena Thakur Ryan Severins Mitchell Kronenberg Amy R. Howell 《Bioorganic & medicinal chemistry letters》2009,19(15):4122-4125
Four 3″- and 4″-deoxy and -fluorogalactosyl ceramides were synthesized, and their ability to stimulate iNKT cells, based on levels of IL-2 production, was assessed in three NKT cell receptor hybridomas. In two of the hybridomas, 1.2 and 2H4, all of the analogs were immunostimulatory, while in the 1.4 hybridoma only the 4″-fluoro analog led to the production of significant levels of IL-2. 相似文献
10.
Traditional taxonomy of hyphomycetes has been based on conidial morphology and development. In order to confirm species level
for the detection and identification of the entomopathogenic fungus, we analysed the species-specific fingerprints to investigate
molecular characteristics within isolates of six species and to resolve morphologically atypical isolates. The extent of fingerprint
profile observed by RAPD was sufficient to confirm the species level of all the isolates. The genetic similarity among morphologically
identified isolates of each species was considerably higher, allowing us to conclude that all the isolates are of same species.
These results establish a molecular framework for further taxonomic, phylogenetic and comparative biological investigations. 相似文献