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71.
K.M. Khawar S. Gulbitti-Onarici S. Çöçü S. Erisen C. Sancak S. Özcan 《Biologia Plantarum》2004,48(3):441-444
Transformation of fenugreek (Trigonella foenumgraecum) was carried out with A281 oncogenic strain of Agrobacterium tumefaciens using root, cotyledon and hypocotyl explants excised from 1-week-old seedlings, which showed that the plant was highly susceptible to transformation. Tumors (calli) were selected on 50 mg dm–3 kanamycin. They were analyzed for -glucuronidase (GUS) expression. Presence of uidA (gus) gene, was confirmed by polymerase chain reaction (PCR) amplification. 相似文献
72.
Regulation of chromatin structure is an essential component of the DNA damage response (DDR), which effectively preserves the integrity of DNA by a network of multiple DNA repair and associated signaling pathways. Within the DDR, chromatin is modified and remodeled to facilitate efficient DNA access, to control the activity of repair proteins and to mediate signaling. The mammalian ISWI family has recently emerged as one of the major ATP-dependent chromatin remodeling complex families that function in the DDR, as it is implicated in at least 3 major DNA repair pathways: homologous recombination, non-homologous end-joining and nucleotide excision repair. In this review, we discuss the various manners through which different ISWI complexes regulate DNA repair and how they are targeted to chromatin containing damaged DNA. 相似文献
73.
Historically, medical concerns about the deleterious effects of closely inbred marriages have focused on the risk posed by recessive Mendelian disease, with much less attention to developmental instability. We studied the effects of inbreeding (first‐cousin marriage) on growth and fluctuating asymmetry of 200 full‐term infants (101 inbred and 99 outbred) whose parents were of similar socioeconomic status in Sivas Province, Turkey. In addition to differences in their mean inbreeding coefficients (f = 1/16 for first cousins and f < 1/1,024 for unrelated parents), the consanguineous parents were less well educated (3 years, on average for both husbands and wives). We measured weight, height, head circumference, and chest circumference of the newborns, as well as four bilateral traits (ear width, ear length, and second and fourth digit lengths). After taking education into account, none of the measures of size (weight, height, head circumference, and chest circumference) and fluctuating asymmetry differed between the inbred and outbred groups. Male children of well‐educated parents, however, were larger and had less fluctuating asymmetry. Female children of well‐educated parents weighed more than those of less well‐educated parents, but were otherwise indistinguishable for height, head circumference, chest circumference, and fluctuating asymmetry. We conclude that inbreeding depression causes neither an increase in fluctuating asymmetry of full‐term newborns, nor a decrease in body size. Unmeasured variables correlated with education appear to have an effect on fluctuating asymmetry and size of male children and only a weak effect on size (weight) of female children. Am J Phys Anthropol 153:45–51, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
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75.
Mapping DNA damage‐dependent genetic interactions in yeast via party mating and barcode fusion genetics 下载免费PDF全文
J Javier Díaz‐Mejía Albi Celaj Joseph C Mellor Atina Coté Attila Balint Brandon Ho Pritpal Bansal Fatemeh Shaeri Marinella Gebbia Jochen Weile Marta Verby Anna Karkhanina YiFan Zhang Cassandra Wong Justin Rich D'Arcy Prendergast Gaurav Gupta Sedide Öztürk Daniel Durocher Grant W Brown Frederick P Roth 《Molecular systems biology》2018,14(5)
Condition‐dependent genetic interactions can reveal functional relationships between genes that are not evident under standard culture conditions. State‐of‐the‐art yeast genetic interaction mapping, which relies on robotic manipulation of arrays of double‐mutant strains, does not scale readily to multi‐condition studies. Here, we describe barcode fusion genetics to map genetic interactions (BFG‐GI), by which double‐mutant strains generated via en masse “party” mating can also be monitored en masse for growth to detect genetic interactions. By using site‐specific recombination to fuse two DNA barcodes, each representing a specific gene deletion, BFG‐GI enables multiplexed quantitative tracking of double mutants via next‐generation sequencing. We applied BFG‐GI to a matrix of DNA repair genes under nine different conditions, including methyl methanesulfonate (MMS), 4‐nitroquinoline 1‐oxide (4NQO), bleomycin, zeocin, and three other DNA‐damaging environments. BFG‐GI recapitulated known genetic interactions and yielded new condition‐dependent genetic interactions. We validated and further explored a subnetwork of condition‐dependent genetic interactions involving MAG1, SLX4, and genes encoding the Shu complex, and inferred that loss of the Shu complex leads to an increase in the activation of the checkpoint protein kinase Rad53. 相似文献
76.
The functionality of membrane proteins is often modulated by the surrounding membrane. Here, we investigated the effect of membrane reconstitution of purified cytochrome c oxidase (CytcO) on the kinetics and thermodynamics of internal electron and proton-transfer reactions during O(2) reduction. Reconstitution of the detergent-solubilized enzyme in small unilamellar soybean phosphatidylcholine vesicles resulted in a lowering of the pK(a) in the pH dependence profile of the proton-uptake rate. This pK(a) change resulted in decreased proton-uptake rates in the pH range of ~6.5-9.5, which is explained in terms of lowering of the pK(a) of an internal proton donor within CytcO. At pH 7.5, the rate decreased to the same extent when vesicles were prepared from the pure zwitterionic lipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or the anionic lipid 1,2-dioleoyl-sn-glycero-3-phospho(1-rac-glycerol) (DOPG). In addition, a small change in the internal Cu(A)-heme a electron equilibrium constant was observed. This effect was lipid-dependent and explained in terms of a lower electrostatic potential within the membrane-spanning part of the protein with the anionic DOPG lipids than with the zwitterionic DOPC lipids. In conclusion, the data show that the membrane significantly modulates internal charge-transfer reactions and thereby the function of the membrane-bound enzyme. 相似文献
77.
In this study, Schiff bases were synthesized by utilizing the reaction of 4- and 5-aminoindane with substituted benzaldehydes. After the reduction of isolated Schiff bases with NaBH4, the corresponding secondary amine derivatives were obtained. The structures of all synthesized molecules were confirmed by 1H-NMR, 13C-NMR, FT-IR, and ESI-MS. Antioxidant activities of all synthesized molecules were investigated by DPPH method, and IC50 values were calculated. In addition, antibacterial activities of targets were investigated by the well diffusion method, and then MIC99 values were calculated. While only four of the sixteen synthesized molecules showed a high level of antioxidant activity, all of the molecules exhibited biological activity against Gram-positive and Gram-negative bacteria to varying degrees. In addition, all the synthesized molecules showed high antifungal activity. In antioxidant capacity studies, the IC50 values of 2-(((2,3-dihydro-1H-inden-5-yl)amino)methyl)-6-methoxyphenol ( 4 d ) and 2-(((2,3-dihydro-1H-inden-4-yl)amino)methyl)-6-methoxyphenol ( 7 d ) were determined to be 18.1 μg and 35.1 μg, respectively, and these values are much stronger than BHT (butylated hydroxytoluene) and BHA (butylated hydroxyanisole) used as positive controls. The fact that targets have the same core structure with different substituents has revealed a good structure-activity relationship. 相似文献
78.
Samet Evyapan Emine Elçin Oruç-Emre Yusuf Sıcak Ayşegül Karaküçük-İyidoğan Gizem Tatar Yılmaz Mehmet Öztürk 《化学与生物多样性》2023,20(8):e202300626
In this study, new chiral thiourea and 1,3-thiazolidine-4,5-dione derivatives were synthesized, it was aimed to evaluate the various biological activities and molecular docking of these compounds. Firstly, the new thioureas ( 1 – 16 ) were obtained by reacting 1-naphthylisothiocyanate with different chiral amines. Then, the chiral thioureas were cyclized with oxalyl chloride to obtain 1,3-thiazolidine-4,5-dione derivatives ( 17 – 32 ). All compounds were evaluated with several in vitro antioxidant and enzyme inhibition activities. Compound 30 was the most active compound against AChE, with a value of IC50=8.09±0.58 μM. On the other hand, all compounds were tested in silico absorption, distribution, metabolism, and excretion (ADME) assays to better understand their bioavailability. These physicochemical properties, pharmacokinetics, and drug-likeness of all compounds were calculated using SwissADME. Furthermore, according to molecular docking analyses compound 30 exhibited significant binding affinities for all enzymes. Based on our overall observations, compound 30 could be recommended as a potential lead for the therapuetic of Alzheimer's. 相似文献
79.
Sesselja Omarsdottir Eydis Einarsdottir Helga M. Ögmundsdottir Jona Freysdottir Elin Soffia Olafsdottir Tadeusz F. Molinski Jörundur Svavarsson 《Phytochemistry Reviews》2013,12(3):517-529
Iceland is an island in the North Atlantic Ocean, with an exclusive economic zone of 200 nautical miles that is largely unexplored with respect to chemical constituents of the marine biota. Iceland is a geothermally active area and hosts both hot and cold adapted organisms on land and in the ocean around it. In particular, the confluence of cold and warm water masses and geothermal activity creates a unique marine environment that has not been evaluated for the potential of marine natural product diversity. Marine organisms need to protect themselves from other organisms trying to overgrow, and some need to secure their place on the bottom of the ocean. Unexplored and unique areas such as the hydrothermal vent site at the sea floor in Eyjafjordur are of particular interest. In 1992 a collaborative research programme on collecting and identifying benthic invertebrates around Iceland (BIOICE) was established, with participation of Icelandic and foreign institutes, universities and taxonomists on benthic invertebrates from all over the world. Since the programme started almost 2,000 species have been identified and of those 41 species are new to science. Our recent bioprospecting project is directed towards the first systematic investigation of the marine natural product diversity of benthic invertebrates occurring in Icelandic waters, and their potential for drug-lead discovery in several key therapeutic areas. 相似文献
80.
Theta oscillations are related to cognitive functions and reflect functional integration of frontal and medial temporal structures into coherent neurocognitive networks. This study assessed event-related theta oscillations in medication-free, euthymic patients with bipolar disorder upon auditory oddball paradigm. Twenty-two DSM-IV euthymic bipolar I (n = 19) and II (n = 3) patients and twenty-two healthy subjects were included. Patients were euthymic for at least 6 months, and psychotropic-free for at least 2 weeks. EEG was recorded at 30 electrode sites. Auditory oddball paradigm and sensory stimuli were used. Event-related Oscillations were analyzed using adaptive filtering in two different theta frequency bands (4–6 Hz, 6–8 Hz). In healthy subjects, slow theta (4–6 Hz) responses were significantly higher than those of euthymic patients upon target, non-target and sensory stimuli (p < 0.05). Fast theta (6–8 Hz) responses of healthy subjects were significantly higher than those of euthymic patients upon target-only stimuli (p < 0.05). Reduced theta oscillations during auditory processing provide strong quantitative evidence of activation deficits in related networks in bipolar disorder. Fast theta responses are related to cognitive functions, whereas slow theta responses are related to sensory processes more than cognitive processes. 相似文献