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Max A B Haase Jacek Kominek Dana A Opulente Xing-Xing Shen Abigail L LaBella Xiaofan Zhou Jeremy DeVirgilio Amanda Beth Hulfachor Cletus P Kurtzman Antonis Rokas Chris Todd Hittinger 《Genetics》2021,217(2)
Dollo’s law posits that evolutionary losses are irreversible, thereby narrowing the potential paths of evolutionary change. While phenotypic reversals to ancestral states have been observed, little is known about their underlying genetic causes. The genomes of budding yeasts have been shaped by extensive reductive evolution, such as reduced genome sizes and the losses of metabolic capabilities. However, the extent and mechanisms of trait reacquisition after gene loss in yeasts have not been thoroughly studied. Here, through phylogenomic analyses, we reconstructed the evolutionary history of the yeast galactose utilization pathway and observed widespread and repeated losses of the ability to utilize galactose, which occurred concurrently with the losses of GALactose (GAL) utilization genes. Unexpectedly, we detected multiple galactose-utilizing lineages that were deeply embedded within clades that underwent ancient losses of galactose utilization. We show that at least two, and possibly three, lineages reacquired the GAL pathway via yeast-to-yeast horizontal gene transfer. Our results show how trait reacquisition can occur tens of millions of years after an initial loss via horizontal gene transfer from distant relatives. These findings demonstrate that the losses of complex traits and even whole pathways are not always evolutionary dead-ends, highlighting how reversals to ancestral states can occur. 相似文献
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Marzena Wieczorkowska Jacek Zielonka Joanna Celińska Jan Adamus Ewa Ciesielska Andrzej Marcinek 《Free radical research》2013,47(11):1157-1162
It is shown that NADH can be effectively oxidized by 1-methyl-3-nitropyridine in non-enzymatic and enzyme-mediated processes. Mechanistic issues of these reactions are discussed. These processes seem to contribute to the observed cytotoxicity of 1-methyl-3-nitropyridine. A key role of 1-methyl-3-nitropyridinyl radical formed in the enzyme-mediated processes is emphasized. 相似文献
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Andrzej Tukiendorf Leszek Miszczyk Jacek Bojarski 《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2013,29(5):513-519
In the paper, we suggest a damped sinusoidal function be used to model a regenerative response of mucosa in time after the radiotherapy treatment. The medical history of 389 RT patients irradiated within the years 1994–2000 at the Radiotherapy Department, Cancer Center, Maria Sk?odowska-Curie Memorial Institute of Oncology, Gliwice, Poland, was taken into account. In the analyzed group of patients, the number of observations of a single patient ranged from 2 to 25 (mean = 8.3, median = 8) with severity determined by use of Dische's scores from 0 to 24 (mean = 7.4, median = 7). Statistical modeling of radiation-induced mucositis was performed for five groups of patients irradiated within the following radiotherapy schedules: CAIR, CB, Manchester, CHA–CHA, and Conventional. All of the regression parameters of the assumed model, i.e. amplitude, damping coefficient, angular frequency, phase of component, and offset, estimated in the analysis were statistically significant (p-value < 0.05) for the radiotherapy schedules. The model was validated using a non-oscillatory function. Following goodness-of-fit statistics, the damped sinusoidal function fits the data better than the non-oscillatory damped function. Model curves for harmonic characteristics with confidence intervals were plotted separately for each of the RT schedules and together in a combined design. The suggested model might be helpful in the numeric evaluation of the RT toxicity in the groups of patients under analysis as it allows for practical comparisons and treatment optimization. A statistical approach is also briefly described in the paper. 相似文献
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Abstract Sodium iodide was found to catalyse the phosphorylation of nucleosides by phosphorodiester derivatives such as chlorophosphates, pyrophosphates and triazolides. A similar catalytic effect, but on phosphorochloridates only, was also exerted by iodine. 相似文献
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Par J. Garegg Tor Regberg Jacek Stawinski Roger Strömberg 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):429-432
Abstract Oxidation of nucleoside H-phosphonate diesters has been investigated using dipyridyl disulphide, hexachloroacetone and iodine, under various reaction conditions. 相似文献
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An efficient entry to nucleoside 3′-H-phosphonoselenoate monoesters via phosphinate intermediates was developed. It involves a reaction of suitably protected nucleosides with triethylammonium phosphinate in the presence of pivaloyl chloride, followed by selenization of the intermediate nucleoside phosphinates with triphenylphosphine selenide, to produce the corresponding nucleoside H-phosphonoselenoates in 86–92% yields. 相似文献
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Abstract In this paper a short review is given of synthetic methods for the preparation of nucleoside phosphorofluoridates, nucleoside phosphorofluoridothioates and nucleoside phosphorofluoridodithioates. 相似文献