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排序方式: 共有569条查询结果,搜索用时 15 毫秒
1.
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
2.
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
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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
6.
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
7.
Mehta Vikrant Meena Jaipal Kasana Harit Munshi Anjana Chander Harish 《Molecular biology reports》2022,49(9):8517-8526
Molecular Biology Reports - An emerging component of Unfolded Protein Response (UPR) pathway, cation transport regulator homolog 1 (CHAC1) has been conferred with the ability to degrade... 相似文献
8.
Zhongyuan Ren Le Duy Do Géraldine Bechkoff Saida Mebarek Nermin Keloglu Saandia Ahamada Saurabh Meena David Magne Slawomir Pikula Yuqing Wu René Buchet 《PloS one》2015,10(3)
A direct and continuous approach to determine simultaneously protein and phosphate concentrations in cells and kinetics of phosphate release from physiological substrates by cells without any labeling has been developed. Among the enzymes having a phosphatase activity, tissue non-specific alkaline phosphatase (TNAP) performs indispensable, multiple functions in humans. It is expressed in numerous tissues with high levels detected in bones, liver and neurons. It is absolutely required for bone mineralization and also necessary for neurotransmitter synthesis. We provided the proof of concept that infrared spectroscopy is a reliable assay to determine a phosphatase activity in the osteoblasts. For the first time, an overall specific phosphatase activity in cells was determined in a single step by measuring simultaneously protein and substrate concentrations. We found specific activities in osteoblast like cells amounting to 116 ± 13 nmol min-1 mg-1 for PPi, to 56 ± 11 nmol min-1 mg-1 for AMP, to 79 ± 23 nmol min-1 mg-1 for beta-glycerophosphate and to 73 ± 15 nmol min-1 mg-1 for 1-alpha-D glucose phosphate. The assay was also effective to monitor phosphatase activity in primary osteoblasts and in matrix vesicles. The use of levamisole – a TNAP inhibitor- served to demonstrate that a part of the phosphatase activity originated from this enzyme. An IC50 value of 1.16 ± 0.03 mM was obtained for the inhibition of phosphatase activity of levamisole in osteoblast like cells. The infrared assay could be extended to determine any type of phosphatase activity in other cells. It may serve as a metabolomic tool to monitor an overall phosphatase activity including acid phosphatases or other related enzymes. 相似文献
9.
Mukesh Kumar Meena Sanjay Ghawana Atish Sardar Vikas Dwivedi Hitaishi Khandal Riti Roy Debasis Chattopadhyay 《PloS one》2015,10(4)
Calcium ion (Ca2+) is a ubiquitous second messenger that transmits various internal and external signals including stresses and, therefore, is important for plants’ response process. Calcineurin B-like proteins (CBLs) are one of the plant calcium sensors, which sense and convey the changes in cytosolic Ca2+-concentration for response process. A search in four leguminous plant (soybean, Medicago truncatula, common bean and chickpea) genomes identified 9 to 15 genes in each species that encode CBL proteins. Sequence analyses of CBL peptides and coding sequences (CDS) suggested that there are nine original CBL genes in these legumes and some of them were multiplied during whole genome or local gene duplication. Coding sequences of chickpea CBL genes (CaCBL) were cloned from their cDNAs and sequenced, and their annotations in the genome assemblies were corrected accordingly. Analyses of protein sequences and gene structures of CBL family in plant kingdom indicated its diverse origin but showed a remarkable conservation in overall protein structure with appearance of complex gene structure in the course of evolution. Expression of CaCBL genes in different tissues and in response to different stress and hormone treatment were studied. Most of the CaCBL genes exhibited high expression in flowers. Expression profile of CaCBL genes in response to different abiotic stresses and hormones related to development and stresses (ABA, auxin, cytokinin, SA and JA) at different time intervals suggests their diverse roles in development and plant defence in addition to abiotic stress tolerance. These data not only contribute to a better understanding of the complex regulation of chickpea CBL gene family, but also provide valuable information for further research in chickpea functional genomics. 相似文献
10.
Kamlesh K. Meena Manish Kumar Snehasish Mishra Sanjay Kumar Ojha Goraksha C. Wakchaure Biplab Sarkar 《Indian journal of microbiology》2015,55(2):151-162
Group-wise diversity of sediment methylotrophs of Chilika lake (Lat. 19°28′–19°54′N; Long. 85°06′–85°35′E) Odisha, India at various identified sites was studied. Both the culturable and unculturable (metagenome) methylotrophs were investigated in the lake sediments employing both mxaF and 16S rRNA genes as markers. ARDRA profiling, 16S rRNA gene sequencing, PAGE profiling of HaeIII, EcoRI restricted mxaF gene and the mxaF gene sequences using culture-dependent approach revealed the relatedness of α-proteobacteria and Methylobacterium, Hyphomicrobium and Ancyclobacter sp. The total viable counts of the culturable aerobic methylotrophs were relatively higher in sediments near the sea mouth (S3; Panaspada), also demonstrated relatively high salinity (0.1 M NaCl) tolerance. Metagenomic DNA from the sediments, amplified using GC clamp mxaF primers and resolved through DGGE, revealed the diversity within the unculturable methylotrophic bacterium Methylobacterium organophilum, Ancyclobacter aquaticus, Burkholderiales and Hyphomicrobium sp. Culture-independent analyses revealed that up to 90 % of the methylotrophs were unculturable. The study enhances the general understandings of the metagenomic methylotrophs from such a special ecological niche.