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991.
David B. Lowry Tierney L. Logan Luca Santuari Christian S. Hardtke James H. Richards Leah J. DeRose-Wilson John K. McKay Saunak Sen Thomas E. Juenger 《The Plant cell》2013,25(9):3266-3279
The regulation of gene expression is crucial for an organism’s development and response to stress, and an understanding of the evolution of gene expression is of fundamental importance to basic and applied biology. To improve this understanding, we conducted expression quantitative trait locus (eQTL) mapping in the Tsu-1 (Tsushima, Japan) × Kas-1 (Kashmir, India) recombinant inbred line population of Arabidopsis thaliana across soil drying treatments. We then used genome resequencing data to evaluate whether genomic features (promoter polymorphism, recombination rate, gene length, and gene density) are associated with genes responding to the environment (E) or with genes with genetic variation (G) in gene expression in the form of eQTLs. We identified thousands of genes that responded to soil drying and hundreds of main-effect eQTLs. However, we identified very few statistically significant eQTLs that interacted with the soil drying treatment (GxE eQTL). Analysis of genome resequencing data revealed associations of several genomic features with G and E genes. In general, E genes had lower promoter diversity and local recombination rates. By contrast, genes with eQTLs (G) had significantly greater promoter diversity and were located in genomic regions with higher recombination. These results suggest that genomic architecture may play an important a role in the evolution of gene expression. 相似文献
992.
Erin A. Mordecai Krijn P. Paaijmans Leah R. Johnson Tal Ben‐Horin Emily de Moor Amy McNally Samraat Pawar Sadie J. Ryan Thomas C. Smith Kevin D. Lafferty 《Ecology letters》2013,16(1):22-30
The ecology of mosquito vectors and malaria parasites affect the incidence, seasonal transmission and geographical range of malaria. Most malaria models to date assume constant or linear responses of mosquito and parasite life‐history traits to temperature, predicting optimal transmission at 31 °C. These models are at odds with field observations of transmission dating back nearly a century. We build a model with more realistic ecological assumptions about the thermal physiology of insects. Our model, which includes empirically derived nonlinear thermal responses, predicts optimal malaria transmission at 25 °C (6 °C lower than previous models). Moreover, the model predicts that transmission decreases dramatically at temperatures > 28 °C, altering predictions about how climate change will affect malaria. A large data set on malaria transmission risk in Africa validates both the 25 °C optimum and the decline above 28 °C. Using these more accurate nonlinear thermal‐response models will aid in understanding the effects of current and future temperature regimes on disease transmission. 相似文献
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Fatoba Abiodun J. Adeleke Victoria T. Maharaj Leah Okpeku Moses Adeniyi Adebayo A. Adeleke Matthew A. 《International journal of peptide research and therapeutics》2021,27(4):2183-2198
International Journal of Peptide Research and Therapeutics - Enterococcus faecium has emerged as the fourth most commonly isolated nosocomial pathogen due to its resistance to commonly used... 相似文献
996.
Aimee Louise Bryant 《Journal of bioethical inquiry》2011,8(3):281-288
Upon first consideration, the desire of an individual to amputate a seemingly healthy limb is a foreign, perhaps unsettling,
concept. It is, however, a reality faced by those who suffer from body integrity identity disorder (BIID). In seeking treatment,
these individuals request surgery that challenges both the statutory provisions that sanction surgical operations and the
limits of consent as a defence in New Zealand. In doing so, questions as to the influence of public policy and the extent
of personal autonomy become important. Beyond legal issues, BIID confronts dominant conceptions of bodily integrity, medical
treatment, and ethical obligations. This paper seeks to identify the relevant public policy concerns raised by BIID in New
Zealand and the limits of autonomy, before moving on to consider how BIID sufferers may legally seek the treatment they require
and how a doctor might be protected from criminal proceedings for assault for performing this treatment. It will be argued
that it is possible to legally consent to the amputation of a healthy limb as medical treatment and that public perception
should not be allowed to take precedence over this right. 相似文献
997.
Myeloid differentiation proteins MD-1 and MD-2 have both been shown to form a heterogeneous collection of oligomers when expressed in absence of their respective receptor, RP105 and TLR4. The biological relevance of these oligomers is not clear. Only monomeric proteins have been found to be active and able to trigger an immune response to endotoxin by modulating the TLR4 pathway. In this study, we produced variants of MD-1 and MD-2 in Pichia pastoris. To minimize the time and expense of initial expression tests, small-scale cultures have been set up to allow the rapid identification of the highest expressing clone and the optimal expression conditions. The expression vectors used, the site of linearization and the locus of integration affected the yield of transformation. Next we screened culture additives and found that they significantly increased the fraction of monomeric proteins secreted in the culture medium (up to 15% of the total MD protein produced). We confirmed their presence by size-exclusion chromatography. Optimal anti-aggregation agents were protein-dependent except for LPS that presented stabilizing effects for all MD proteins. Contrary to previous reports, this study suggests that MD-1 can bind to LPS. 相似文献
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Robbins N Uppuluri P Nett J Rajendran R Ramage G Lopez-Ribot JL Andes D Cowen LE 《PLoS pathogens》2011,7(9):e1002257
Fungal biofilms are a major cause of human mortality and are recalcitrant to most treatments due to intrinsic drug resistance. These complex communities of multiple cell types form on indwelling medical devices and their eradication often requires surgical removal of infected devices. Here we implicate the molecular chaperone Hsp90 as a key regulator of biofilm dispersion and drug resistance. We previously established that in the leading human fungal pathogen, Candida albicans, Hsp90 enables the emergence and maintenance of drug resistance in planktonic conditions by stabilizing the protein phosphatase calcineurin and MAPK Mkc1. Hsp90 also regulates temperature-dependent C. albicans morphogenesis through repression of cAMP-PKA signalling. Here we demonstrate that genetic depletion of Hsp90 reduced C. albicans biofilm growth and maturation in vitro and impaired dispersal of biofilm cells. Further, compromising Hsp90 function in vitro abrogated resistance of C. albicans biofilms to the most widely deployed class of antifungal drugs, the azoles. Depletion of Hsp90 led to reduction of calcineurin and Mkc1 in planktonic but not biofilm conditions, suggesting that Hsp90 regulates drug resistance through different mechanisms in these distinct cellular states. Reduction of Hsp90 levels led to a marked decrease in matrix glucan levels, providing a compelling mechanism through which Hsp90 might regulate biofilm azole resistance. Impairment of Hsp90 function genetically or pharmacologically transformed fluconazole from ineffectual to highly effective in eradicating biofilms in a rat venous catheter infection model. Finally, inhibition of Hsp90 reduced resistance of biofilms of the most lethal mould, Aspergillus fumigatus, to the newest class of antifungals to reach the clinic, the echinocandins. Thus, we establish a novel mechanism regulating biofilm drug resistance and dispersion and that targeting Hsp90 provides a much-needed strategy for improving clinical outcome in the treatment of biofilm infections. 相似文献
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