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181.
Zorica S. Mitić Snežana Č. Jovanović Bojan K. Zlatković Biljana M. Nikolić Gordana S. Stojanović Petar D. Marin 《化学与生物多样性》2017,14(5)
Chemical compositions of needle essential oils of 27 taxa from the section Pinus, including 20 and 7 taxa of the subsections Pinus and Pinaster, respectively, were compared in order to determine chemotaxonomic significance of terpenes at infrageneric level. According to analysis of variance, six out of 31 studied terpene characters were characterized by a high level of significance, indicating statistically significant difference between the examined subsections. Agglomerative hierarchical cluster analysis has shown separation of eight groups, where representatives of subsect. Pinaster were distributed within the first seven groups on the dendrogram together with P. nigra subsp. laricio and P. merkusii from the subsect. Pinus. On the other hand, the eighth group included the majority of the members of subsect. Pinus. Our findings, based on terpene characters, complement those obtained from morphological, biochemical, and molecular parameters studied over the past two decades. In addition, results presented in this article confirmed that terpenes are good markers at infrageneric level. 相似文献
182.
Dragana Jakovljević Milan Stanković Biljana Bojović Marina Topuzović 《Acta Physiologiae Plantarum》2017,39(11):243
Basil cultivars are among most used crops worldwide, but high level of morpho-physiological variations is mainly due to the cultivation characteristics. The present study aimed to investigate the physiological changes and the accumulation of secondary metabolites as a response to prolonged nutrient deprivation in shoots and roots of sweet basil (Ocimum basilicum L. var. minimum). Sweet basil seedlings were grown in media with quarter, half and full strength of micro and macronutrients under different levels of KNO3 alone or in combination with different levels of NH4NO3. Evaluated parameters included characteristics of germination, development of leaves, content of photosynthetic pigments and responses of different parameters related to oxidative stress. While the early growth is influenced mainly due to NH4NO3 presence, all the levels of nutrient supply were found to trigger and maintain the antioxidant defence system of sweet basil seedlings. With the variations among seedling parts, the ammonium nutrition was notably enhanced levels of activity of SOD, CAT, A-POX, G-POX and P-POX, but had no effect on total antioxidant activity and total phenolic content, including flavonoids, which is mainly accumulated in nutrient deprived roots. In addition, phenylalanine ammonia-lyase activity was analysed and potential pathways of secondary metabolites synthesis were discussed. The enzymatic and non-enzymatic system in O. basilicum var. minimum seedlings was capable to reverse the stress conditions during growth under nutrient deprivation. 相似文献
183.
184.
Biljana Balen Marijana Krsnik-Rasol Alina D Zamfir Ivana Zadro Sergey Y Vakhrushev Jasna Peter-Katalinic 《Journal of biomolecular techniques》2007,18(3):162-172
Artificial environmental conditions in tissue culture, such as elevated relative humidity and rich nutrient medium, can influence and modify tissue growth and induce spontaneous changes from characteristic organization pattern to unorganized callus. As succulent plants with crassulacean acid metabolism, cacti are particularly susceptible to this altered growth environment. Glycosylated proteins of Mammillaria gracillis tissues cultivated in vitro, separated by SDS-PAGE, were detected with Con A after the transfer of proteins onto the nitrocellulose membrane. The glycan components were further characterized by affinity blotting with different lectins (GNA, DSA, PNA, and RCA(120)). The results revealed significant differences in glycoprotein pattern among the investigated cactus tissues (shoot, callus, hyperhydric regenerant, and tumor). To test whether the N-glycosylation of the same protein can vary in different developmental stages of cactus tissue, the N-glycans were analyzed by MALDI-TOF MS after in-gel deglycosylation of the excised 38-kDa protein band. Paucimannosidic-type N-glycans were detected in oligosaccharide mixtures from shoot and callus, while the hyperhydric regenerant and tumor shared glycans of complex type. The hybrid oligosaccharide structures were found only in tumor tissue. These results indicate that the adaptation of plant cells to artificial environment in tissue culture is reflected in N-glycosylation, and structures of N-linked glycans vary with different developmental stages of Mammillaria gracillis tissues. 相似文献
185.
Biljana Atanasovska Georgi Bozhinovski Dijana Plaseska-Karanfilska Lyubomira Chakalova 《PloS one》2012,7(10)
β-Thalassemias and abnormal hemoglobin variants are among the most common hereditary abnormalities in humans. Molecular characterization of the causative genetic variants is an essential part of the diagnostic process. In geographic areas with high hemoglobinopathy prevalence, such as the Mediterranean region, a limited number of genetic variants are responsible for the majority of hemoglobinopathy cases. Developing reliable, rapid and cost-effective mutation-specific molecular diagnostic assays targeting particular populations greatly facilitates routine hemoglobinopathy investigations. We developed a one-tube single-nucleotide primer extension assay for the detection of eight common Mediterranean β-thalassemia mutations: Codon 5 (-CT); CCT(Pro)->C–, Codon 6 (-A); GAG(Glu)->G-G, Codon 8 (-AA); AAG(Lys)->–G, IVS-I-1 (G->A), IVS-I-6 (T->C), IVS-I-110 (G->A), Codon 39 (C->T), and IVS-II-745 (C->G), as well as the hemoglobin S variant beta 6(A3) Glu>Val. We validated the new assay using previously genotyped samples obtaining 100% agreement between independent genotyping methods. Our approach, applicable in a range of Mediterranean countries, offers a combination of high accuracy and rapidity exploiting standard techniques and widely available equipment. It can be further adapted to particular populations by including/excluding assayed mutations. We facilitate future modifications by providing detailed information on assay design. 相似文献
186.
Marija Milovanovic Vladislav Volarevic Biljana Ljujic Gordana Radosavljevic Ivan Jovanovic Nebojsa Arsenijevic Miodrag L. Lukic 《PloS one》2012,7(9)
The administration of interleukin 33 and deletion of IL-33 receptor, ST2 molecule, affects the induction of autoimmunity in different experimental models of human autoimmune diseases. The aim of this study was to analyze the effect of ST2 deletion on the induction of experimental autoimmune encephalomyelitis (EAE) in resistant BALB/c mice. Mice were immunized with MOG35–55 peptide or disease was induced by passive transfer of encephalitogenic singenic cells and EAE was clinically and histologically evaluated. Expression of intracellular inflammatory cytokines, markers of activation and chemokine receptors on lymphoid tissue and CNS infiltrating mononuclear cells was analyzed by flow cytometry. We report here that deletion of ST2−/− molecule abrogates resistance of BALB/c mice to EAE induction based on clinical and histopathological findings. Brain and spinal cord infiltrates of ST2−/− mice had significantly higher number of CD4+ T lymphocytes containing inflammatory cytokines compared to BALB/c WT mice. Adoptive transfer of ST2−/− primed lymphocytes induced clinical signs of the disease in ST2−/− as well as in WT mice. MOG35–55 restimulated ST2−/− CD4+ cells as well as ex vivo analyzed lymph node cells had higher expression of T-bet and IL-17, IFN-γ, TNF-α and GM-CSF in comparison with WT CD4+ cells. ST2−/− mice had higher percentages of CD4+ cells expressing chemokine receptors important for migration to CNS in comparison with WT CD4+ cells. Draining lymph nodes of ST2−/− mice contained higher percentage of CD11c+CD11b+CD8− cells containing inflammatory cytokines IL-6 and IL-12 with higher expression of activation markers. Transfer of ST2−/− but not WT dendritic cells induced EAE in MOG35–55 immunized WT mice. Our results indicate that ST2 deficiency attenuates inherent resistance of BALB/c mice to EAE induction by enhancing differentiation of proinflammatory antigen presenting cells and consecutive differentiation of encephalitogenic T cells in the draining lymph node rather than affecting their action in the target tissue. 相似文献
187.
Mirta Tkalec Petra Peharec ?tefani? Petra Cvjetko Sandra ?iki? Mirjana Pavlica Biljana Balen 《PloS one》2014,9(1)
The objective of the present study was to investigate the effects of cadmium-zinc (Cd-Zn) interactions on their uptake, oxidative damage of cell macromolecules (lipids, proteins, DNA) and activities of antioxidative enzymes in tobacco seedlings as well as roots and leaves of adult plants. Seedlings and plants were exposed to Cd (10 µM and 15 µM) and Zn (25 µM and 50 µM) as well as their combinations (10 µM or 15 µM Cd with either 25 µM or 50 µM Zn). Measurement of metal accumulation exhibited that Zn had mostly positive effect on Cd uptake in roots and seedlings, while Cd had antagonistic effect on Zn uptake in leaves and roots. According to examined oxidative stress parameters, in seedlings and roots individual Cd treatments induced oxidative damage, which was less prominent in combined treatments, indicating that the presence of Zn alleviates oxidative stress. However, DNA damage found in seedlings, and lower glutathione reductase (GR) and superoxide dismutase (SOD) activity recorded in both seedlings and roots, after individual Zn treatments, indicate that Zn accumulation could impose toxic effects. In leaves, oxidative stress was found after exposure to Cd either alone or in combination with Zn, thus implying that in this tissue Zn did not have alleviating effects. In conclusion, results obtained in different tobacco tissues suggest tissue-dependent Cd-Zn interactions, which resulted in activation of different mechanisms involved in the protection against metal stress. 相似文献
188.
Biljana Nikolić Vele Tešević Iris Ðorđević Petar D. Marin Srdjan Bojović 《化学与生物多样性》2009,6(2):193-203
This study is the first report on the composition and variability of essential oil in the relic, endemic, and vulnerable tree species Serbian spruce, Picea omorika, in its natural populations. In the needles of 108 trees of four natural populations, 49 components of essential oils were identified. The main compounds were bornyl acetate (29.2%), camphene (18.7%), and α‐pinene (12.9%). Fourteen additional components had the contents of up to 0.5%: α‐cadinol (6.1%), limonene (5.8%), santene (3.5%), (E)‐hex‐2‐enal (2.9%), T‐cadinol (2.9%), δ‐cadinene (2.3%), tricyclene (2.1%), myrcene (1.6%), β‐pinene (1.2%), borneol (0.9%), germacrene D (0.9%), α‐muurolene (0.6%), and two unidentified compounds. Population IV from Mile?evka Canyon had a much higher content of bornyl acetate (42.9%). Populations I–III from Mt. Tara were more abundant in sesquiterpenes (up to 18.2%). The content of bornyl acetate, the multi‐variation analyses according to seven selected components, especially the cluster analysis and genetic analysis of α‐cadinol, which suggested the monogenic type of heredity, showed a clear differentiation of the two geographic areas, the similarity of populations I–III from the area of Mt. Tara, and the separation of the population IV from Mile?evka Canyon. 相似文献
189.
Edlira B. Clark Biljana Jovov Arun K. Rooj Catherine M. Fuller Dale J. Benos 《The Journal of biological chemistry》2010,285(35):27130-27143
Acid-sensing ion channel 1 (ASIC1) is a H+-gated channel of the amiloride-sensitive epithelial Na+ channel (ENaC)/degenerin family. ASIC1 is expressed mostly in the central and peripheral nervous system neurons. ENaC and ASIC function is regulated by several serine proteases. The type II transmembrane serine protease matriptase activates the prototypical αβγENaC channel, but we found that matriptase is expressed in glioma cells and its expression is higher in glioma compared with normal astrocytes. Therefore, the goal of this study was to test the hypothesis that matriptase regulates ASIC1 function. Matriptase decreased the acid-activated ASIC1 current as measured by two-electrode voltage clamp in Xenopus oocytes and cleaved ASIC1 expressed in oocytes or CHO K1 cells. Inactive S805A matriptase had no effect on either the current or the cleavage of ASIC1. The effect of matriptase on ASIC1 was specific, because it did not affect the function of ASIC2 and no matriptase-specific ASIC2 fragments were detected in oocytes or in CHO cells. Three matriptase recognition sites were identified in ASIC1 (Arg-145, Lys-185, and Lys-384). Site-directed mutagenesis of these sites prevented matriptase cleavage of ASIC1. Our results show that matriptase is expressed in glioma cells and that matriptase specifically cleaves ASIC1 in heterologous expression systems. 相似文献
190.
eIF4E is a central node of an RNA regulon that governs cellular proliferation 总被引:4,自引:0,他引:4 下载免费PDF全文
Culjkovic B Topisirovic I Skrabanek L Ruiz-Gutierrez M Borden KL 《The Journal of cell biology》2006,175(3):415-426
This study demonstrates that the eukaryotic translation initiation factor eIF4E is a critical node in an RNA regulon that impacts nearly every stage of cell cycle progression. Specifically, eIF4E coordinately promotes the messenger RNA (mRNA) export of several genes involved in the cell cycle. A common feature of these mRNAs is a structurally conserved, approximately 50-nucleotide element in the 3' untranslated region denoted as an eIF4E sensitivity element. This element is sufficient for localization of capped mRNAs to eIF4E nuclear bodies, formation of eIF4E-specific ribonucleoproteins in the nucleus, and eIF4E-dependent mRNA export. The roles of eIF4E in translation and mRNA export are distinct, as they rely on different mRNA elements. Furthermore, eIF4E-dependent mRNA export is independent of ongoing RNA or protein synthesis. Unlike the NXF1-mediated export of bulk mRNAs, eIF4E-dependent mRNA export is CRM1 dependent. Finally, the growth-suppressive promyelocytic leukemia protein (PML) inhibits this RNA regulon. These data provide novel perspectives into the proliferative and oncogenic properties of eIF4E. 相似文献