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31.
Nick S. Fradgley James Bacon Alison R. Bentley Germano Costa-Neto Andrew Cottrell Jose Crossa Jaime Cuevas Matthew Kerton Edward Pope Stéphanie M. Swarbreck Keith A. Gardner 《Global Change Biology》2023,29(5):1296-1313
Wheat is a major crop worldwide, mainly cultivated for human consumption and animal feed. Grain quality is paramount in determining its value and downstream use. While we know that climate change threatens global crop yields, a better understanding of impacts on wheat end-use quality is also critical. Combining quantitative genetics with climate model outputs, we investigated UK-wide trends in genotypic adaptation for wheat quality traits. In our approach, we augmented genomic prediction models with environmental characterisation of field trials to predict trait values and climate effects in historical field trial data between 2001 and 2020. Addition of environmental covariates, such as temperature and rainfall, successfully enabled prediction of genotype by environment interactions (G × E), and increased prediction accuracy of most traits for new genotypes in new year cross validation. We then extended predictions from these models to much larger numbers of simulated environments using climate scenarios projected under Representative Concentration Pathways 8.5 for 2050–2069. We found geographically varying climate change impacts on wheat quality due to contrasting associations between specific weather covariables and quality traits across the UK. Notably, negative impacts on quality traits were predicted in the East of the UK due to increased summer temperatures while the climate in the North and South-west may become more favourable with increased summer temperatures. Furthermore, by projecting 167,040 simulated future genotype–environment combinations, we found only limited potential for breeding to exploit predictable G × E to mitigate year-to-year environmental variability for most traits except Hagberg falling number. This suggests low adaptability of current UK wheat germplasm across future UK climates. More generally, approaches demonstrated here will be critical to enable adaptation of global crops to near-term climate change. 相似文献
32.
Henipaviruses and lyssaviruses target nucleolar treacle protein and regulate ribosomal RNA synthesis
Stephen M. Rawlinson Tianyue Zhao Katie Ardipradja Yilin Zhang Patrick F. Veugelers Jennifer A. Harper Cassandra T. David Vinod Sundaramoorthy Gregory W. Moseley 《Traffic (Copenhagen, Denmark)》2023,24(3):146-157
The nucleolus is a common target of viruses and viral proteins, but for many viruses the functional outcomes and significance of this targeting remains unresolved. Recently, the first intranucleolar function of a protein of a cytoplasmically-replicating negative-sense RNA virus (NSV) was identified, with the finding that the matrix (M) protein of Hendra virus (HeV) (genus Henipavirus, family Paramyxoviridae) interacts with Treacle protein within nucleolar subcompartments and mimics a cellular mechanism of the nucleolar DNA-damage response (DDR) to suppress ribosomal RNA (rRNA) synthesis. Whether other viruses utilise this mechanism has not been examined. We report that sub-nucleolar Treacle targeting and modulation is conserved between M proteins of multiple Henipaviruses, including Nipah virus and other potentially zoonotic viruses. Furthermore, this function is also evident for P3 protein of rabies virus, the prototype virus of a different RNA virus family (Rhabdoviridae), with Treacle depletion in cells also found to impact virus production. These data indicate that unrelated proteins of viruses from different families have independently developed nucleolar/Treacle targeting function, but that modulation of Treacle has distinct effects on infection. Thus, subversion of Treacle may be an important process in infection by diverse NSVs, and so could provide novel targets for antiviral approaches with broad specificity. 相似文献
33.
34.
Clark E. Hartsock III Jeffrey K. Lewis Ian Leslie Joseph A. Pope Jr. Larry B. Tsai Raj Sachdev Shi-Yuan Meng 《Biotechnology letters》1995,17(10):1025-1030
Summary A synthetic lactose-inducible promoter was chosen to study host cell responses to the over-expression of heterologous genes. Fermentations were conducted to compare the effect of induction strategies on the synthesis of -galactosidase versus the production of recombinant protein. The levels of lactose, IPTG and glucose during induction were manipulated to adjust the utilization of lactose as the inducer and/or the carbon source. In addition, the involvement of the gal operon in lactose metabolism was also explored in order to optimize lactose transport and utilization during induction. 相似文献
35.
N. Black J. Griffiths C. Pope A. Bowling P. Abel 《BMJ (Clinical research ed.)》1997,315(7121):1493-1498
OBJECTIVES: To describe the impact of surgery for stress incontinence on the severity of symptoms, other mental and physical symptoms, and overall health. To describe the incidence of postoperative complications. DESIGN: Prospective cohort study; questionnaires completed by patients before and 3, 6, and 12 months after surgery. Questionnaires completed by surgeons both before and after surgery. SETTING: 18 hospitals in the North Thames region. SUBJECTS: 442 women treated surgically for stress incontinence between January 1993 and June 1994. 367 women returned the 3 month questionnaire; 364 returned the 6 month questionnaire; and 359 returned the 12 month questionnaire. 49 surgeons provided perioperative information on 285 of the 442 women and postoperative information on 278. MAIN OUTCOME MEASURES: Stress incontinence symptom severity index, other urinary symptoms, bowel function, mental health, complications, global measures. RESULTS: Most women (288; 87%) reported an improvement in the severity of their stress incontinence, though only 92 (28%) were cured (continent). These improvements persisted for at least 12 months. The likelihood of improvement was similar regardless of whether urodynamic pressure studies had been conducted before surgery. Following surgery, women were less likely to suffer from urinary frequency, nocturia, postvoid fullness, dysuria, and urgency. While mental health improved for 194 (71%), a quarter of women reported deterioration. Only 37 (10%) were satisfied with postoperative pain control. A third experienced one or more complications while in hospital, most commonly difficulty urinating. This problem affected 1 in 11 women after discharge. A year after surgery two thirds of women reported feeling better (251; 72%), that the outcome met or exceeded their expectations (230; 66%), and that they would recommend the operation to a friend in a similar situation (239; 68%), and that they would recommend the operation to a friend in a similar situation (239; 68%). Surgeons tended to be more optimistic about the effects of surgery; they were satisfied with the outcome in 176 (85%) cases and would again treat 245 (94%) of the women as they had done previously. CONCLUSIONS: Although surgery reduces the severity of stress incontinence it is not as effective as current textbooks suggest. Women considering surgery should be provided with more accurate information on the likelihood of an improvement in symptoms and the occurrence of complications, including postoperative pain. Urgency and urge incontinence should not be considered contraindications to surgery. The need for urodynamic assessment before surgery should be reappraised. 相似文献
36.
Growing appreciation of the multiple functions of proteolytic enzymes in intracellular protein degradation and post-translational modification, in the release of biologically active macromolecules and peptides from precursors and in cellular protein regulation and quality control has stimulated interest in proteases in neurobiology and neuropathology. In this article, the proteinases and peptidases thus far studied in the human central nervous system are reviewed with respect to their enzymology, anatomical and cytological distributions and contributions to neurological and psychiatric disease states. Though information concerning brain proteases in man is fragmentary, it suffices to establish the importance of these complex systems for advancing knowledge of human cerebral function in health and disease.The authors are privileged to submit this contribution for the Special Issue of Neurochemical Research honoring Professor K. A. C. Elliott—distinguished pioneer in neurochemistry and a cherished mentor and former colleague of one of us (AP). 相似文献
37.
The bile was determined to be the major excretory route for 14C-warfarin in the rat with approximately 10% of the administered dose excreted within 5 hours after injection. Relatively little radioactivity appeared in the faces, indicating that considerable enterohepatic recycling was taking place. Less than 4% of the radioactivity in the bile could be extracted with organic solvents. Following incubation of the bile with β-glucuronidase or rat gut flora, however, the bulk of the radioactivity was extractable. The extent of gut flora-mediated hydrolysis of these polar biliary warfarin conjugates was approximately the same as obtained with β-glucuronidase. Approximately of the gut flora-hydrolyzable conjugates were labile and subject to nonenzymatic hydrolysis at 37 C for 24 h. Chromatographic examination of the extracts from β-glucuronidase-treated bile revealed the presence of warfarin and 4′-, 6-, 7-, and 8-hydroxywarfarin. Warfarin and 7-hydroxywarfarin were the most abundant metabolites in the extracts. 相似文献
38.
Growth of Legionella pneumophila in association with blue-green algae (cyanobacteria). 总被引:35,自引:22,他引:13 下载免费PDF全文
Legionella pneumophila (Legionnaires disease bacterium) of serogroup 1 was isolated from an algal-bacterial mat community growing at 45 degrees C in a man-made thermal effluent. This isolate was grown in mineral salts medium at 45 degrees C in association with the blue-green alga (cyanobacterium) Fischerella sp. over a pH range of 6.9 to 7.6. L. pneumophila was apparently using algal extracellular products as its carbon and energy sources. These observations indicate that the temperature, pH, and nutritional requirements of L. pneumophila are not as stringent as those previously observed when cultured on complex media. This association between L. pneumophila and certain blue-green algae suggests an explanation for the apparent widespread distribution of the bacterium in nature. 相似文献
39.
A J Buller R Pope 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1977,278(961):295-305
While it has been recognized for many years that different limb muscles belonging to the same mammal may have markedly differing contractile characteristics, it is only comparatively recently that it has been demonstrated that these differences depend upon the motor innervation. By appropriately changing the peripheral nerve innervating a mammalian skeletal muscle, it is possible to change dramatically the contractile behaviour of the reinnervated muscle. The manner by which the motor innervation determines the nature of a muscle fibre's contractile machinery is not completely understood, but it appears that the number and pattern of motor nerve impulses reaching the muscle play an important role. The biochemical changes occurring within muscle fibres whose contractile properties have been modified by altered motor innervation include the synthesis of different contractile proteins. 相似文献
40.
The numbers of presumptiveLegionella pneumophila cells in waters and sediments of nine different cooling towers located on the same site in the northeastern United States were determined at approximately monthly intervals for 18 months. All systems received makeup water from the same source and received the same chemical treatments. PresumptiveL. pneumophila were found in both water and sediment samples from all systems on all sampling dates. An important result of this study was the finding that tower sediments represent large reservoirs ofL. pneumophila. The only correlation between levels of presumptiveL. pneumophila and any of the physical, chemical, or operating characteristics evaluated was with winter shutdown and drainage followed by a nonoperational period. These systems showed a definite seasonal response with the highest levels of presumptiveL. pneumophila found in the summer and fall. Systems operated year round showed relatively constant numbers ofL. pneumophila in both water and sediments. 相似文献