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911.
Marcin Kadej Krzysztof Zając Adrian Smolis Dariusz Tarnawski Adam Malkiewicz 《Journal of Insect Conservation》2016,20(3):395-406
Decline and fragmentation of natural habitats, such as old-growth forests, reduces their availability in the landscape. The solution to this problem for many forest-dwelling species, may be colonization of alternative habitats, such as parks, orchards or rural avenues, located in the highly fragmented agricultural landscape. Our main objective was to determine the effect of both habitat quality parameters and isolation from potential forest habitats, as primary habitats, on the occurrence of the hermit beetle (Osmoderma) in rural avenues in south-western Poland. The study was based on the results of an inventory of the species in 201 rural avenues within an area of approx. 30,000 km2. Occurrence of the hermit beetle in such alternative habitats was affected by both habitat quality parameters and connectivity with suitable forest habitats. The species occurrence in an avenue was significantly positively affected by mean tree diameter and diversity of tree species, but probability of occurrence decreased as isolation of avenue from the deciduous forest increased. Moreover, in the study area the hermit beetle seemed to avoid alleys with a large proportion of Acer platanoides, Fraxinus excelsior and Populus spp. Spatially isolated roadside avenues have limited value in the preservation of the hermit beetle in the long term conservation management of the species. Conservation plans in such habitats should therefore take into account surrounding suitable habitats. 相似文献
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Kai Jiang Ce Zhang Durgarao Guttula Fan Liu Jeroen A. van?Kan Christophe Lavelle Krzysztof Kubiak Antoine Malabirade Alain Lapp Véronique Arluison Johan R.C. van?der?Maarel 《Nucleic acids research》2015,43(8):4332-4341
Hfq is a bacterial pleiotropic regulator that mediates several aspects of nucleic acids metabolism. The protein notably influences translation and turnover of cellular RNAs. Although most previous contributions concentrated on Hfq''s interaction with RNA, its association to DNA has also been observed in vitro and in vivo. Here, we focus on DNA-compacting properties of Hfq. Various experimental technologies, including fluorescence microscopy imaging of single DNA molecules confined inside nanofluidic channels, atomic force microscopy and small angle neutron scattering have been used to follow the assembly of Hfq on DNA. Our results show that Hfq forms a nucleoprotein complex, changes the mechanical properties of the double helix and compacts DNA into a condensed form. We propose a compaction mechanism based on protein-mediated bridging of DNA segments. The propensity for bridging is presumably related to multi-arm functionality of the Hfq hexamer, resulting from binding of the C-terminal domains to the duplex. Results are discussed in regard to previous results obtained for H-NS, with important implications for protein binding related gene regulation. 相似文献
913.
Karbownik M Stasiak M Zasada K Zygmunt A Lewinski A 《Journal of cellular biochemistry》2005,95(1):131-138
Potassium bromate (KBrO3) is a prooxidant and carcinogen, inducing thyroid tumors. Melatonin and indole-3-propionic acid (IPA) are effective antioxidants. Some antioxidative effects of propylthiouracil (PTU)--a thyrostatic drug--have been found. The aim of the study was to compare protective effects of melatonin, IPA, and PTU against lipid peroxidation in the thyroids, collected from rats treated with KBrO3, and in homogenates of porcine thyroids, incubated in the presence of KBrO3. Wistar rats were administered KBrO3 (110 mg/kg b.w., i.p., on the 10th day of the experiment) and/or melatonin, or IPA (0.0645 mmol/kg b.w., i.p., twice daily, for 10 days), or PTU (0.025% solution in drinking water, for 10 days). Homogenates of porcine thyroids were incubated for 30 min in the presence of KBrO3 (5 mM) plus one of the antioxidants: melatonin (0.01, 0.1, 0.5, 1.0, 5.0, 7.5 mM), or IPA (0.01, 0.1, 0.5, 1.0, 5.0, 7.5, 10.0 mM), or PTU (0.01, 0.1, 0.5, 1.0, 5.0, 7.5, 10.0 mM). The level of lipid peroxidation products (MDA + 4-HDA) was measured spectrophotometrically in thyroid homogenates. In vivo pretreatment with either melatonin or with IPA or with PTU decreased lipid peroxidation caused by KBrO3--injections in rat thyroid gland. Under in vitro conditions, PTU (5.0, 7.5, and 10.0 mM), but neither melatonin nor IPA, reduced KBrO3-related lipid peroxidation in the homogenates of porcine thyroids. In conclusion, melatonin and IPA may be of great value as protective agents under conditions of exposure to KBrO3. 相似文献
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Kali Janes Joshua W. Little Chao Li Leesa Bryant Collin Chen Zhoumou Chen Krzysztof Kamocki Timothy Doyle Ashley Snider Emanuela Esposito Salvatore Cuzzocrea Erhard Bieberich Lina Obeid Irina Petrache Grant Nicol William L. Neumann Daniela Salvemini 《The Journal of biological chemistry》2014,289(30):21082-21097
919.
Mark Held Hongwei Hou Marilyn Kehl Alexandre Tromas Shusei Sato Satoshi Tabata Stig Uggerhøj Andersen Jens Stougaard Loretta Ross Krzysztof Szczyglowski 《The Plant journal : for cell and molecular biology》2014,78(5):811-821
A symbiotic mutant of Lotus japonicus, called sunergos1‐1 (suner1‐1), originated from a har1‐1 suppressor screen. suner1‐1 supports epidermal infection by Mesorhizobium loti and initiates cell divisions for organogenesis of nodule primordia. However, these processes appear to be temporarily stalled early during symbiotic interaction, leading to a low nodule number phenotype. This defect is ephemeral and near wild‐type nodule numbers are reached by suner1‐1 at a later point after infection. Using an approach that combined map‐based cloning and next‐generation sequencing we have identified the causative mutation and show that the suner1‐1 phenotype is determined by a weak recessive allele, with the corresponding wild‐type SUNER1 locus encoding a predicted subunit A of a DNA topoisomerase VI. Our data suggest that at least one function of SUNER1 during symbiosis is to participate in endoreduplication, which is an essential step during normal differentiation of functional, nitrogen‐fixing nodules. 相似文献
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