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Djordje Malenčić Jelena Cvejić Vesna Tepavčević Mira Bursać Biljana Kiprovski Miloš Rajković 《Central European Journal of Biology》2013,8(9):921-929
Soybean [Glycine max (L.) Merr.] cultivars (Meli, Alisa, Sava and 1511/99) were grown up to V1 phase (first trifoliate and one node above unifoliate) and then inoculated with Sclerotinia sclerotiorum (Lib.) de Bary under controlled conditions. Changes in L-phenylalanine ammonia-lyase (PAL) activity and isoflavone phytoalexins were recorded 12, 24, 48 and 72 h after the inoculation. Results showed an increase in PAL activity in all four examined soybean cultivars 48 h after the inoculation, being the highest in Alisa (2-fold higher). Different contents of total daidzein, genistein, glycitein and coumestrol were detected in all samples. Alisa and Sava increased their total isoflavone content (33.9% and 6.2% higher than control, respectively) as well as 1511/99, although 48 h after the inoculation its content decreased significantly. Meli exhibited the highest rate of coumestrol biosynthesis (72 h after the inoculation) and PAL activity (48 h after the inoculation). All investigated cultivars are invariably susceptible to this pathogen. Recorded changes could point to possible differences in mechanisms of tolerance among them. 相似文献
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Biljana R. Deki Milenko N. Risti Marko Z. Mladenovi Vidoslav S. Deki Novica R. Risti Vladimir Ranelovi Niko S. Radulovi 《化学与生物多样性》2019,16(7)
Some carnation species (Dianthus spp., Caryophyllaceae) exhibit a strong resistance to drought stress that is connected with the increased surface wax formation. Wax composition is unknown for the majority of Dianthus spp. Herein, mass spectral and gas chromatographic data, in combination with synthesis and chemical transformations (transesterification and synthesis of dimethyl disulfide adducts), enabled the identification of 151 constituents of diethyl‐ether washings of fresh flowers of Dianthus cruentus Griseb . from Serbia. The flower wax contained, along with the dominant ubiquitous long‐chain n‐alkanes, homologous series of n‐ and branched (iso‐ and anteiso‐) long‐chain hexyl alkanoates/alkenoates and alkyl/alkenyl benzoates. The branching position in the mentioned hexyl esters was probed by synthesis of esters of three isomeric hexanols that were spectrally characterized (1H‐ and 13C‐NMR, IR, MS). The washings also contained long‐chain (Z)‐ and (E)‐alkenes (C23?C35) with several different double bond regiochemistries. Fifty‐five of these constituents (eight hexyl esters, two benzoates, and forty‐five alkenes) were detected for the first time in Plantae, while ten of these represent completely new compounds. The rare occurrence of these wax constituents makes them possible chemotaxonomic markers of this particular Dianthus sp. 相似文献
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Jakovljevic Biljana Nikolic Turnic Tamara Jeremic Nevena Jeremic Jovana Bradic Jovana Ravic Marko Jakovljevic Vladimir Lj. Jelic Djordje Radovanovic Dragan Pechanova Olga Zivkovic Vladimir 《Molecular and cellular biochemistry》2019,453(1-2):111-119
Molecular and Cellular Biochemistry - Melatonin is a crucial neurohormone synthesized in the pineal gland that influences the physiology of animals. The molecular mechanism of norepinephrine... 相似文献
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Acid-sensing ion channels in malignant gliomas 总被引:6,自引:0,他引:6
Berdiev BK Xia J McLean LA Markert JM Gillespie GY Mapstone TB Naren AP Jovov B Bubien JK Ji HL Fuller CM Kirk KL Benos DJ 《The Journal of biological chemistry》2003,278(17):15023-15034
High grade glioma cells derived from patient biopsies express an amiloride-sensitive sodium conductance that has properties attributed to the human brain sodium channel family, also known as acid-sensing ion channels (ASICs). This amiloride-sensitive conductance was not detected in cells obtained from normal brain tissue or low grade or benign tumors. Differential gene profiling data showed that ASIC1 and ASIC2 mRNA were present in normal and low grade tumor cells. Although ASIC1 was present in all of the high grade glial cells examined, ASIC2 mRNA was detected in less than half. The main purpose of our work was to examine the molecular mechanisms that may underlie the constitutively activated sodium currents present in high grade glioma cells. Our results show that 1) gain-of-function mutations of ASIC1 were not present in a number of freshly resected and cultured high grade gliomas, 2) syntaxin 1A inhibited ASIC currents only when ASIC1 and ASIC2 were co-expressed, and 3) the inhibition of ASIC currents by syntaxin 1A had an absolute requirement for either gamma- or delta-hENaC. Transfection of cultured cells originally derived from high grade gliomas (U87-MG and SK-MG1) with ASIC2 abolished basal amiloride-sensitive sodium conductance; this inhibition was reversed by dialysis of the cell interior with Munc-18, a syntaxin-binding protein that typically blocks the interaction of syntaxin with other proteins. Thus, syntaxin 1A cannot inhibit Na(+) permeability in the absence of adequate plasma membrane ASIC2 expression, accounting for the observed functional expression of amiloride-sensitive currents in high grade glioma cells. 相似文献
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