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1.
Janina Li
yt Kotryna Kvederavi
it Audron Ruknait Egl Godliauskait Povilas Gibas Vita Tomkut Graina Petraityt Viktoras Masevi
ius Saulius Klimaauskas Edita Kriukien 《Open biology》2022,12(3)
The formation of three oxidative DNA 5-methylcytosine (5mC) modifications (oxi-mCs)—5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC)—by the TET/JBP family of dioxygenases prompted intensive studies of their functional roles in mammalian cells. However, the functional interplay of these less abundant modified nucleotides in other eukaryotic lineages remains poorly understood. We carried out a systematic study of the content and distribution of oxi-mCs in the DNA and RNA of the basidiomycetes Laccaria bicolor and Coprinopsis cinerea, which are established models to study DNA methylation and developmental and symbiotic processes. Quantitative liquid chromatography–tandem mass spectrometry revealed persistent but uneven occurrences of 5hmC, 5fC and 5caC in the DNA and RNA of the two organisms, which could be upregulated by vitamin C. 5caC in RNA (5carC) was predominantly found in non-ribosomal RNA, which potentially includes non-coding, messenger and small RNA species. Genome-wide mapping of 5hmC and 5fC using the single CG analysis techniques hmTOP-seq and foTOP-seq pointed at involvement of oxi-mCs in the regulation of gene expression and silencing of transposable elements. The implicated diverse roles of 5mC and oxi-mCs in the two fungi highlight the epigenetic importance of the latter modifications, which are often neglected in standard whole-genome bisulfite analyses. 相似文献
2.
Abstract Many classic models of speciation incorporate assortative mating based on mating groups, such as plants with different flowering times, and they investigate whether an ecological trait under disruptive natural selection becomes genetically associated with the selectively neutral mating trait. It is well known that this genetic association is potently destroyed by recombination. In this note, we point out a more fundamental difficulty: if a "knife-edge" symmetry assumption of previous models is violated, then the mating trait is no longer neutral and sexual selection eliminates the polymorphism in the mating locus. This result strengthens the growing consensus that magic traits are the more likely route to nonallopatric speciation. We expand the model assuming also ecological selection on the mating trait and investigate the conditions for natural selection to overcome sexual selection and maintain mating polymorphism; we find that the combination of natural and sexual selection can cause also bistability of allele frequencies. 相似文献
3.
Agata Karklelyte Konstantinas Povilas Valuckas Romas Griskevicius Ernestas Janulionis Eduardas Aleknavicius 《Reports of Practical Oncology and Radiotherapy》2018,23(4):284-289
Purpose
The aim of our study was to perform the final analysis of acute toxicity and quality of life data obtained from 221 consecutive patients who suffered from intermediate-to-high risk prostate cancer.Methods
In this trial, 221 patients were randomized to receive either hypofractionated (63?Gy in 20 fractions, 4 fractions/week) or conventionally fractionated (76?Gy in 38 fractions, 5 fractions/week) radiotherapy to the prostate and seminal vesicles. Elective pelvic lymph node irradiation with 46?Gy in 23 fractions sequentially and 44?Gy in 20 fractions simultaneously was also applied.Results
There was no statistically significant difference in acute GU and GI toxicity in men treated with hypofractionated (SIB) (Arm 2) in comparison with patients who had conventional fractionation (Arm 1) radiation therapy. Multivariate analysis using logistic regression showed statistical significant association between acute GU?≥?1 and PTV(LN) (p?=?0.008) only. We found out that clinically relevant decrease (CRD) was significantly higher only in the urinary domain of Arm 1 at month 3 (p?=?0.02).Conclusion
Our study demonstrated that hypofractionated radiotherapy was associated with a small but insignificant increase of acute toxicity. The reduction of overall treatment time has no significant influence on patients’ QOL in any domain. 相似文献4.
Hydronium tetrafluoroborate ion pairs, H3O+·BF4 - have been shown computationally to be unstable toward decomposition, in the absence of solvation or electrostatic interactions existing in crystals. As the proton NMR spectrum of a hydronium salt with the octanesulfonate-antimony pentachloride complex anion was reported in freon solution, we investigated the hypothesis that larger ionic clusters were present in the nonpolar solvent. It was found that the dimer (H3O+·BF4 -)2 was stable at the MP2/6-31G* level. GIAO-B3LYP chemical shift calculations with the same basis set and also with the 6-31G**, 6-31++G**, 6-311++G**, dzvp, tzp, tz2p, and qz2p basis sets conducted on the hydronium fluoroborate dimer reproduce the main features of the experimental spectrum: the existence of two signals with a two-to-one intensity ratio and the more intense resonance at higher frequency (more deshielded). The alternative structures, of hydronium tetrafluoroborate ion pairs with one and with two hydrogen bonds between anion and cation, give calculated chemical shifts which are farther from the experimental values. 相似文献
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6.
Development of microsatellite markers and comparative mapping for bovine chromosome 19 总被引:2,自引:0,他引:2
Previous research has mapped an ovulation rate quantitative trait locus (QTL) to bovine chromosome 19. In an effort to enhance comparative mapping information and develop additional markers for refined QTL mapping, microsatellite markers were developed in a targeted approach. A bovine bacterial artificial chromosome (BAC) library was screened for loci with either known or predicted locations on bovine chromosome 19. An average of 6.4 positive BAC were identified per screened locus. A total of 10 microsatellite markers were developed for five targeted loci with heterozygosity of 7-83% in a sample of reference family parents. The newly developed markers were typed on reference families along with four previously mapped marker loci and used to create a linkage map. Comparison of locus order between human and cattle provides support for previously observed rearrangement. One of the mapped loci myotubularin related protein 4 (MTMR4) potentially extends the proximal boundary of a conserved linkage group. 相似文献
7.
Chiara Lee Shoko Yashiro David L. Dotson Povilas Uzdavinys So Iwata Mark S.P. Sansom Christoph von Ballmoos Oliver Beckstein David Drew Alexander D. Cameron 《The Journal of general physiology》2014,144(6):529-544
Sodium–proton antiporters rapidly exchange protons and sodium ions across the membrane to regulate intracellular pH, cell volume, and sodium concentration. How ion binding and release is coupled to the conformational changes associated with transport is not clear. Here, we report a crystal form of the prototypical sodium–proton antiporter NhaA from Escherichia coli in which the protein is seen as a dimer. In this new structure, we observe a salt bridge between an essential aspartic acid (Asp163) and a conserved lysine (Lys300). An equivalent salt bridge is present in the homologous transporter NapA, but not in the only other known crystal structure of NhaA, which provides the foundation of most existing structural models of electrogenic sodium–proton antiport. Molecular dynamics simulations show that the stability of the salt bridge is weakened by sodium ions binding to Asp164 and the neighboring Asp163. This suggests that the transport mechanism involves Asp163 switching between forming a salt bridge with Lys300 and interacting with the sodium ion. pKa calculations suggest that Asp163 is highly unlikely to be protonated when involved in the salt bridge. As it has been previously suggested that Asp163 is one of the two residues through which proton transport occurs, these results have clear implications to the current mechanistic models of sodium–proton antiport in NhaA. 相似文献
8.
The faunistic composition of the family Cossidae (Lepidoptera) of the Socotra Archipelago is revised. Five species are recognized, including two new species (Mormogystia brandstetteri and Meharia hackeri), and dubious identifications and records are discussed. Adults and genitalia are illustrated and bionomic details, DNA barcodes and a synonymic checklist for Socotran cossids are provided. A review of their distribution reveals that at least 80 percent of Socotra's cossids are unique to the archipelago, which is renowned for its endemism. A checklist listing all the species from generas Meharia, Mormogystia, Aethalopteryx, Azygophleps, as well as the synonymy and distribution is provided. 相似文献
9.
Twonew Eospilarctia species and one new subspecies from China, Myanmar and Vietnam, respectively, are described. Superficially the new species Eospilarctia maciaisp. n., Eospilarctia naumannisp. n. and Eospilarctia yuennanica fansipanassp. n. resemble related congeners but they can be distinguished by the differences in wing pattern, genitalia and distribution provided. Eospilarctia yuennanica guangdonga Dubatolov, Kishida & Wang, 2008 is upgraded to species level. A checklist of the genus Eospilarctia and a key to the Eospilarctia yuennanica (Daniel, 1943) species-group, based on external characters and male genitalia, is presented. 相似文献
10.
Alisa Palaveniene Volodymyr Harkavenko Vitalina Kharchenko Povilas Daugela Mindaugas Pranskunas Gintaras Juodzbalys Nataliya Babenko Jolanta Liesiene 《Marine biotechnology (New York, N.Y.)》2018,20(3):363-374
The use of synthetic materials for biomedical applications still presents issues owing to the potential for unfavourable safety characteristics. Currently, there is increasing interest in using natural, marine-derived raw materials for bone tissue engineering. In our study, the endoskeleton of the mollusc Sepia, i.e. cuttlebone (CB), was used with regenerated cellulose (RC) to prepare three-dimensional composite bone grafts. CB microparticles were mechanically immobilised within a cellulose gel, resulting in a macroporous structure upon lyophilisation. The interconnected porous structure of the regenerated cellulose/cuttlebone (RC/CB) composite was evaluated by micro-computed tomography. The porosity of the composite was 80%, and the pore size predominantly ranged from 200 to 500 μm. The addition of CB microparticles increased the specific scaffold surface by almost threefold and was found to be approximately 40 mm?1. The modulus of elasticity and compressive strength of the RC/CB composite were 4.0?±?0.6 and 22.0?±?0.9 MPa, respectively. The biocompatibility of the prepared RC/CB composite with rat hepatocytes and extensor digitorum longus muscle tissue was evaluated. The obtained data demonstrated that both the composite and cellulose matrix samples were non-cytotoxic and had no damaging effects. These results indicate that this RC/CB composite is a novel material suitable for bone tissue-engineering applications. 相似文献