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Integrated requirement of non‐specific and sequence‐specific DNA binding in Myc‐driven transcription
23.
Olwen M. Grace Oscar A. Pérez-Escobar Eve J. Lucas Maria S. Vorontsova Gwilym P. Lewis Barnaby E. Walker Lúcia G. Lohmann Sandra Knapp Peter Wilkie Tiina Sarkinen Iain Darbyshire Eimear Nic Lughadha Alexandre Monro Yannick Woudstra Sebsebe Demissew A. Muthama Muasya Sandra Díaz William J. Baker Alexandre Antonelli 《Trends in plant science》2021,26(5):433-441
24.
Julie Blaising Pierre L. Lévy Claire Gondeau Capucine Phelip Mihayl Varbanov Elodie Teissier Florence Ruggiero Stephen J. Polyak Nicholas H. Oberlies Tijana Ivanovic Eve‐Isabelle Pécheur 《Cellular microbiology》2013,15(11):1866-1882
Hepatitis C virus (HCV) is a global health concern infecting 170 million people worldwide. Previous studies indicate that the extract from milk thistle known as silymarin and its main component silibinin inhibit HCV infection. Here we investigated the mechanism of anti‐HCV action ofsilymarin‐derived compounds at the molecular level. By using live‐cell confocal imaging, single particle tracking, transmission electron microscopy and biochemical approaches on HCV‐infected human hepatoma cells and primary hepatocytes, we show that silibinin potently inhibits HCV infection and hinders HCV entry by slowing down trafficking through clathrin‐coated pits and vesicles. Detailed analyses revealed that silibinin altered the formation of both clathrin‐coated pits and vesicles in cells and caused abnormal uptake and trafficking of transferrin, a well‐known cargo of the clathrin endocytic pathway. Silibinin also inhibited infection by other viruses that enter cells by clathrin‐mediated endocytosis including reovirus, vesicular stomatitis and influenza viruses. Our study demonstrates that silibinin inhibits HCV early steps of infection by affecting endosomal trafficking of virions. It provides new insights into the molecular mechanisms of action of silibinin against HCV entry and also suggests that silibinin is a potential broad‐spectrum antiviral therapy. 相似文献
25.
Nicolas Tête Clémentine Fritsch Eve Afonso Micha?l Coeurdassier Jean-Claude Lambert Patrick Giraudoux Renaud Scheifler 《PloS one》2013,8(6)
Wildlife is exposed to natural (e.g., food availability and quality, parasitism) and anthropogenic stressors (e.g., habitat fragmentation, toxicants). Individual variables (e.g., age, gender) affect behaviour and physiology of animals. Together, these parameters can create both great inter-individual variations in health indicators and interpretation difficulties. We investigated the relevance of body condition and somatic indices (liver, kidneys) as indicators of health status in wood mice (Apodemus sylvaticus, n = 560) captured along a metal pollution gradient in four landscape types (30 sampling squares 500-m sided). The indices were calculated using a recently proposed standard major axis regression instead of an ordinary least square regression. After considering age and gender for the body condition index, no landscape type influence was detected in the indices. However, important index variability was observed between sampling squares; this effect was included as a random effect in linear models. After integrating all individual and environmental variables that may affect the indices, cadmium (Cd) concentrations in both the liver and kidneys were negatively related to body condition and liver indices only for individuals from highly contaminated sites. Lead in the liver was negatively related to the liver index, and Cd in kidneys was positively linked to the kidney index, potentially suggesting metal-induced stress. However, interpretation of these indices as a wildlife ecotoxicology tool should be performed with caution due to the sensitivity of potentially confounding variables (e.g., individual factors and environmental parameters). 相似文献
26.
Zoe Barclay Louise Dickson Derek Robertson Melanie Johnson Pamela Holland Roberta Rosie Liting Sun Helen Jerina Eve Lutz Sue Fleetwood-Walker Rory Mitchell 《Cellular signalling》2013,25(4):814-821
The 5-HT2A receptor (5-HT2AR) is implicated in psychotropic changes within the central nervous system (CNS). A number of polymorphisms have been reported in the 5-HT2AR gene; one of these results in a non-synonymous change, H452Y, in the carboxy-terminal tail of the receptor protein. The minor allele (9% occurrence) has been statistically associated with CNS dysfunction such as impaired memory processing and resistance to neuroleptic treatment in schizophrenic patients. We investigated the impact of H452Y mutation of the 5-HT2AR expressed in COS7 cells on distinctly coupled intracellular signalling pathways from the receptor, focusing on the heterotrimeric G protein-independent phospholipase D (PLD) pathway, compared to the conventional Gq/11-linked phospholipase C (PLC) pathway. The H452Y mutation selectively attenuated PLD signalling, which as in the wild-type receptor, was mediated by a molecular complex involving PLD1 docked to the receptor's carboxy-terminal tail domain. Co-immunoprecipitation and GST-fusion protein experiments revealed that the H452Y mutation selectively reduced PLD1 binding to the receptor. Experiments with blocking peptides to mimic short sections of the 5-HT2AR tail sequence revealed that the peptide spanning residue 452 strongly reduced PLD but not PLC responses of the receptor. Similar observations were made when assessing both PLD responses and PLD-dependent cellular proliferation elicited by activation of 5-HT2ARs natively expressed in MCF-7 cells. Overall these findings indicate that the H452Y polymorphic variant of the 5-HT2AR displays selective disruption of its PLD signalling pathway. This may potentially play a role in the CNS dysfunction associated with the H452Y allele of the 5-HT2AR. 相似文献
27.
Shared and Separate Knowledge among Eight Cultural Groups Based on Ethnobotanical Uses of Rhododendron (Ericaceae) in Yunnan Province, China. Yunnan, a province in southwest China, is known for its cultural diversity of 25 ethnic minorities and its vast Himalayan biodiversity, especially of Rhododendron. Previous literature has shown that some cultural groups share ethnobotanical knowledge while other cultural groups keep their knowledge separate. We investigated factors that may lead to the sharing of knowledge based on the uses of rhododendron among seven cultural minorities (the Bai, Dulong, Lisu, Naxi, Nu, Tibetan, and Yi) and the Han majority. Semistructured interviews about rhododendrons were conducted with approximately 30 individuals in each cultural group. Cluster analyses and a new analysis method were conducted to determine the within-group homogeneity of knowledge of rhododendron uses to test hypotheses related to strength of cultural traditions. The Dulong, Lisu, and Nu were compared with each other as these groups share villages and languages. The Naxi, Tibetan, and Yi live predominantly with members of their cultural group, and are often monolingual; thus, these three cultural minorities were compared. The Bai and Han compose the final comparison as the Bai are increasingly interacting with the local Han majority as tourism grows in that area. The Bai, Dulong, Han, Lisu, and Nu had variable answers within each group, while the Naxi, Tibetan, and Yi have homogeneous knowledge of uses of rhododendron within their cultural group. Among the eight cultural groups compared for this study, factors such as sharing of language, overlap of living situation, and sharing of markets leads to non-homogenous knowledge of rhododendron uses among members of the same cultural group. 相似文献
28.
Philippe Lanotte Marylise Perivier Eve Haguenoer Laurent Mereghetti Christophe Burucoa Stéphane Claverol Christo Atanassov 《PloS one》2013,8(1)
Group B streptococcus (GBS, Streptococcus agalactiae) is a leading cause of meningitis and sepsis in newborns and an etiological agent of meningitis, endocarditis, osteoarticular and soft tissue infections in adults. GBS isolates are routinely clustered in serotypes and in genotypes. At present one GBS sequence type (i.e. ST17) is considered to be closely associated with bacterial invasiveness and novel proteomic biomarkers could make a valuable contribution to currently available GBS typing data. For that purpose we analyzed the protein profiles of 170 genotyped GBS isolates by Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI). Univariate statistical analysis of the SELDI profiles identified four protein biomarkers significantly discriminating ST17 isolates from those of the other sequence types. Two of these biomarkers (MW of 7878 Da and 12200 Da) were overexpressed and the other two (MW of 6258 Da and 10463 Da) were underexpressed in ST17. The four proteins were isolated by mass spectrometry-assisted purification and their tryptic peptides analyzed by LC-MS/MS. They were thereby identified as the small subunit of exodeoxyribonuclease VII, the 50S ribosomal protein L7/L12, a CsbD-like protein and thioredoxin, respectively. In conclusion, we identified four candidate biomarkers of ST17 by SELDI for high-throughput screening. These markers may serve as a basis for further studies on the pathophysiology of GBS infection, and for the development of novel vaccines. 相似文献
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30.
Although visual fixations are commonly used to index stimulus-driven or internally-determined preference, recent evidence suggests that visual fixations can also be a source of decisional bias that moves selection toward the fixated object. These contrasting results raise the question of whether visual fixations always index comparative processes during choice-based tasks, or whether they might better reflect internal preferences when the decision does not carry any economic or corporeal consequences. In two experiments, participants chose which of two objects were more aesthetically pleasing (Exp.1) or appeared more organic (Exp.2), and provided independent aesthetic ratings of the stimuli. Our results demonstrated that fixation parameters were a better index of choice in both decisional domains than of aesthetic preference. The data support models in which visual fixations are specifically related to the evolution of decision processes even when the decision has no tangible consequences. 相似文献