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Amisa Mukaj Jaroslav Pilek Vladana Fotopulosova Andrew Parker Morgan Linda Odenthal-Hesse Emil D Parvanov Jiri Forejt 《Molecular biology and evolution》2020,37(12):3423
The classical definition posits hybrid sterility as a phenomenon when two parental taxa each of which is fertile produce a hybrid that is sterile. The first hybrid sterility gene in vertebrates, Prdm9, coding for a histone methyltransferase, was identified in crosses between two laboratory mouse strains derived from Mus mus musculus and M. m. domesticus subspecies. The unique function of PRDM9 protein in the initiation of meiotic recombination led to the discovery of the basic molecular mechanism of hybrid sterility in laboratory crosses. However, the role of this protein as a component of reproductive barrier outside the laboratory model remained unclear. Here, we show that the Prdm9 allelic incompatibilities represent the primary cause of reduced fertility in intersubspecific hybrids between M. m. musculus and M. m. domesticus including 16 musculus and domesticus wild-derived strains. Disruption of fertility phenotypes correlated with the rate of failure of synapsis between homologous chromosomes in meiosis I and with early meiotic arrest. All phenotypes were restored to normal when the domesticus Prdm9dom2 allele was substituted with the Prdm9dom2H humanized variant. To conclude, our data show for the first time the male infertility of wild-derived musculus and domesticus subspecies F1 hybrids controlled by Prdm9 as the major hybrid sterility gene. The impairment of fertility surrogates, testes weight and sperm count, correlated with increasing difficulties of meiotic synapsis of homologous chromosomes and with meiotic arrest, which we suppose reflect the increasing asymmetry of PRDM9-dependent DNA double-strand breaks. 相似文献
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Vukojević N Sikić J Curković T Juratovac Z Katusić D Sarić B Jukić T 《Collegium antropologicum》2005,29(Z1):25-27
Changes in the eye axial diameter were studied to assess the eye globe impact of conventional operation for retinal detachment. The study included 69 eyes in 69 patients operated on for rhegmatogenous retinal detachment. There were 46.4% of men and 53.6% of women, mean age 52.7 (+/- 15.21) years. Results of preoperative and postoperative ultrasonographic measurement of axial diameter are presented. The mean preoperative and postoperative eye axial diameter was 23.69 (+/- 1.84) mm and 24.43 (+/- 1.91) mm, respectively. Postoperative results showed the axial eye length to increase by a mean of 0.74 (+/- 0.44) mm, yielding a statistically significant difference from the preoperative measurement (p < 0.001). The mean myopia induced by this eyeball elongation was 1.77 D. The encircling band with and without segmental buckling used in surgical repair of retinal detachment creates circular and segmental indentation of the eyeball, thus increasing its axial length. The myopia induced by elongation of the eyeball results in considerable myopia, which requires appropriate correction in the early postoperative period to achieve favorable vision rehabilitation. 相似文献
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Papadopoulos E Collet JF Vukojević V Billeter M Holmgren A Gräslund A Vlamis-Gardikas A 《Biochimica et biophysica acta》2012,1824(12):1401-1408
The gene ygiT (mqsA) of Escherichia coli encodes MqsA, the antitoxin of the motility quorum sensing regulator (MqsR). Both proteins are considered to form a DNA binding complex and to be involved in the formation of biofilms and persisters. We have determined the three-dimensional solution structure of MqsA by high-resolution NMR. The protein comprises a well-defined N-terminal domain with a Zn finger motif usually found in eukaryotes, and a defined C-terminal domain with a typical prokaryotic DNA binding helix-turn-helix motif. The two well-defined domains of MqsA have almost identical structure in solution and in the two published crystal structures of dimeric MqsA bound to either MqsR or DNA. However, the connection of the two domains with a flexible linker yields a large variety of possible conformations in solution, which is not reflected in the crystal structures. MqsA binds Zn with all four cysteines, a stoichiometry of 1:1 and a femtomolar affinity (K(a)≥10(17)M(-1) at 23°C, pH 7.0). 相似文献
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This study presents the carpological heterogeneity of Tragopogon pterodes, an endemic plant species from Balkan Peninsula. The goal of this paper was to determine the variability of morphological characters of achenes and assess the degree of their morphological differentiation relative to the position they occupy in the receptacle. Analysis included four different populations of T. pterodes and examination of 18 (8 qualitative and 10 quantitative) characters of achenes in total. Data analysis employed basic statistic, univariate (ANOVA, Tukey HSD) and multivariate (CDA, CA) analyses to check the level of heterocarpy in this species. The results indicate possible morphological differentiation of three groups of achenes (outer, median and inner achenes), depending of their position on the receptacle. The members of all three types were described, illustrated and compared. The variability of investigated carpological characters in this species is providing important information prior to their further taxonomic treatment. 相似文献
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Considering the fact that some trace elements have influence on the growth and physiological processes in the fungi, the aim
of this study was to resolve the question of whether Fe, Zn, and Se, added to the medium in the different forms, affect activity
of selected Pleurotus eryngii ligninolytic enzymes participating in mandarine peels submerged fermentation. Compared with the control, Fe and Zn showed
stimulatory effect on laccase activity. Reduction in the activity was emphasized with cultivation time, but it was slower
in the presence of Zn than in the presence of Fe. Among studied Se forms, SeO2 was the most unfavorable Se source for laccase activity. All tested trace elements, independent on form, showed stimulatory
effect on the activity of Mn-oxidizing peroxidases on the seventh day of cultivation. Based on the results, it could be concluded
that the presence of the tested trace elements can advance various biotechnological processes among which is biodegradation
of agricultural wastes, potential environmental pollutants. 相似文献
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Neuroprotective Potential and Chemical Profile of Alternatively Cultivated Ganoderma lucidum Basidiocarps 下载免费PDF全文
Jasmina Lj. Ćilerdžić Ivana V. Sofrenić Vele V. Tešević Ilija D. Brčeski Sonja N. Duletić‐Laušević Jelena B. Vukojević Mirjana M. Stajić 《化学与生物多样性》2018,15(5)
Various neurodegenerative diseases are the main challenges to the modern medicine and there is a great need for novel, natural, neuroprotective agents. Ganoderma lucidum is a well‐known medicinal mushroom, which health benefits have been confirmed by numerous studies. As demand for its basidiocarps is increased and traditional cultivation on hardwoods is not environmentally friendly and economically justified, finding of alternative substrates is necessary. The aim of the study was to assess the effect of alternative cultivation substrates on the chemical profile of G. lucidum basidiocarps and their capacity to inhibit acetylcholinesterase and tyrosinase, which higher activity is directly associated with neurodegenerative processes. Extracts of basidiocarps cultivated on alternative substrates, especially on clear wheat straw, showed significantly higher inhibition capacities than extracts of commercially‐grown ones. These extracts were considerably different chemically from commercial basidiocarps extracts and even nine new compounds were isolated from them. Our results suggest that cultivation substrate greatly affect the chemical profile and neuroprotective capacity of obtained basidiocarps and wheat straw is a promising cultivation substrate. 相似文献
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Dr. Jelena Vukojević Dubravka Franić-Mihajlović Miroslav Mihaljčević 《Mycopathologia》1995,132(1):21-25
In trials with various agar media and autoclaved stem pieces of weeds and cultivated plants, perithecia ofDiaporthe helianthi Muntañola-Cvetkoviet al., developed only on autoclaved stem pieces. The simple, useful culture technique for producing perithecia is fully described. 相似文献
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