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71.
目的:克隆核心组蛋白H2A、H2B、H3和H4的基因,表达并纯化组蛋白与谷胱甘肽S-转移酶(GST)的融合蛋白。方法:用PCR方法从乳腺文库中扩增核心组蛋白H2A、H2B、H3和H4的编码序列,分别将其以正确相位与pGEX-KG载体中的GST编码序列融合,得到重组质粒pGST-H2A、pGST-H2B、pGST-H3和pGST-H4,分别转化大肠杆菌BL21,表达融合蛋白GST-H2A、GST-H2B、GST-H3和GST-H4;用谷胱甘肽-Sepharose 4B亲和纯化融合蛋白;用Western印迹检测融合蛋白的表达及纯化。结果:分别构建了核心组蛋白H2A、H2B、H3和H4的融合表达载体;Western印迹检测表明,融合蛋白GST-H2A、GST-H2B、GST-H3和GST-H4获得表达及纯化。结论:表达并纯化了H2A、H2B、H3和H4的融合蛋白,为进一步研究核心组蛋白的功能奠定了基础。 相似文献
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M. F. CLARIDGE J. DEN HOLLANDER J. C. MORGAN 《Biological journal of the Linnean Society. Linnean Society of London》1988,35(1):79-93
Populations of the morphological species, Nilaparvata lugens (Stål), were found to breed and feed on the grass, Leersia hexandra Schwartz, at six sites in Queensland, Australia. They differ from sympatric rice-feeding populations in characters of pulse repetition frequencies of male and female acoustic courtship signals. The two host-derived populations hybridize freely in the laboratory, but in mate choice experiments show very significant preferences for homogametic matings. No indication of field hybridization has been found, so that the two morphologically inseparable populations represent sympatric biological species in Australia.
Populations from L. hexandra are also reported from four localities in Sri Lanka and one in Orissa, India. These resemble previously studied populations from the Philippines. They differ significantly in courtship call characters, both from sympatric rice-associated populations and from allopatric Leersia -associated populations from Australia.
The geographical variation reported for acoustic signals is not consistent with Paterson's recognition concept of species, but may be interpreted in terms of theories of allopatric speciation involving sexual selection for mate recognition signals. 相似文献
Populations from L. hexandra are also reported from four localities in Sri Lanka and one in Orissa, India. These resemble previously studied populations from the Philippines. They differ significantly in courtship call characters, both from sympatric rice-associated populations and from allopatric Leersia -associated populations from Australia.
The geographical variation reported for acoustic signals is not consistent with Paterson's recognition concept of species, but may be interpreted in terms of theories of allopatric speciation involving sexual selection for mate recognition signals. 相似文献
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CA Lei- CHEN Run-Zheng- YIN Zhi-Jian- ZHANG Guo-Xue- CHEN Wen-Hong- SHUI Yu-Min 《Plant Diversity》2015,37(6):733-736
A new species of Gesneriaceae from Honghe County, Southeastern Yunnan, China, Tremacron hongheense WH. Chen & YM. Shui, is described and illustrated. The new species is similar to Tremacron forrestii Craib, but differs by its leaf blade adaxially sparsely long setose (vs. densely white appressed pubescent and sparsely rusty brown villous), corolla tube outside short white glandular (vs. nearly glabrous), corolla lobes red and thickening at apex, especially adaxial lip (vs. yellow and not thickening), stamens 16-18cm long (vs. 04-12cm long), staminode 05-14cm long (vs. 02-04cm long). 相似文献
76.
Grasslands are one of the most widespread landscapes worldwide, covering approximately one-fifth of the world’s land surface, where grazing is a common practice. How carbon storage responds to grazing in steppes remains poorly understood. We quantified the effects of grazing on community composition and species diversity, and carbon storage in two typical grasslands of northeastern China, one in Horqin and the other one in Hulunbeier. In both grasslands, grazing did not influence plant species diversity. However, it substantially decreased aboveground carbon by 31% and 54% in Horqin and Hulunbeier, respectively. Fenced and grazing treatments showed a similar belowground carbon at both locations. The predominant carbon pool in the study grassland ecosystem was found in the upper 100 cm soil depth, from 98.2 to 99.1% of the total carbon storage. There were no significant effects of grazing on soil carbon neither in the whole profile nor in the uppermost 20 cm soil depth in the two study grasslands. Studies on the effects of varying rangeland management, such as region disparity and grazing systems, may have important consequences on species diversity and carbon partitioning, and thus on rangeland stability and ecosystem functioning. 相似文献
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Craig J Smith Hedley CA Emsley Carole M Gavin Rachel F Georgiou Andy Vail Elisa M Barberan Gregory J del Zoppo John M Hallenbeck Nancy J Rothwell Stephen J Hopkins Pippa J Tyrrell 《BMC neurology》2004,4(1):1-8
Background
Cerebral ischaemia initiates an inflammatory response in the brain and periphery. We assessed the relationship between peak values of plasma interleukin-6 (IL-6) in the first week after ischaemic stroke, with measures of stroke severity and outcome.Methods
Thirty-seven patients with ischaemic stroke were prospectively recruited. Plasma IL-6, and other markers of peripheral inflammation, were measured at pre-determined timepoints in the first week after stroke onset. Primary analyses were the association between peak plasma IL-6 concentration with both modified Rankin score (mRS) at 3 months and computed tomography (CT) brain infarct volume.Results
Peak plasma IL-6 concentration correlated significantly (p < 0.001) with CT brain infarct volume (r = 0.75) and mRS at 3 months (r = 0.72). It correlated similarly with clinical outcome at 12 months or stroke severity. Strong associations were also noted between either peak plasma C-reactive protein (CRP) concentration or white blood cell (WBC) count, and all outcome measures.Conclusions
These data provide evidence that the magnitude of the peripheral inflammatory response is related to the severity of acute ischaemic stroke, and clinical outcome. 相似文献79.
Germana B Rona Natalia P Almeida Gilson C Santos Jr Tatiana KS Fidalgo Fabio CL Almeida Elis CA Eleutherio Anderson S Pinheiro 《Journal of cellular biochemistry》2019,120(4):5377-5385
NSD3s, the proline-tryptophan-tryptophan-proline (PWWP) domain-containing, short isoform of the human oncoprotein NSD3, displays high transforming properties. Overexpression of human NSD3s or the yeast protein Pdp3 in Saccharomyces cerevisiae induces similar metabolic changes, including increased growth rate and sensitivity to oxidative stress, accompanied by decreased oxygen consumption. Here, we set out to elucidate the biochemical pathways leading to the observed metabolic phenotype by analyzing the alterations in yeast metabolome in response to NSD3s or Pdp3 overexpression using 1H nuclear magnetic resonance (NMR) metabolomics. We observed an increase in aspartate and alanine, together with a decrease in arginine levels, on overexpression of NSD3s or Pdp3, suggesting an increase in the rate of glutaminolysis. In addition, certain metabolites, including glutamate, valine, and phosphocholine were either NSD3s or Pdp3 specific, indicating that additional metabolic pathways are adapted in a protein-dependent manner. The observation that certain metabolic pathways are differentially regulated by NSD3s and Pdp3 suggests that, despite the structural similarity between their PWWP domains, the two proteins act by unique mechanisms and may recruit different downstream signaling complexes. This study establishes for the first time a functional link between the human oncoprotein NSD3s and cancer metabolic reprogramming. 相似文献
80.
Natália Spitz Francisco CA Mello Natalia Motta Araujo 《Memórias do Instituto Oswaldo Cruz》2015,110(1):151-153
The Brazilian Amazon Region is a highly endemic area for hepatitis B virus (HBV).
However, little is known regarding the genetic variability of the strains circulating
in this geographical region. Here, we describe the first full-length genomes of HBV
isolated in the Brazilian Amazon Region; these genomes are also the first complete
HBV subgenotype D3 genomes reported for Brazil. The genomes of the five Brazilian
isolates were all 3,182 base pairs in length and the isolates were classified as
belonging to subgenotype D3, subtypes ayw2 (n = 3) and ayw3 (n = 2). Phylogenetic
analysis suggested that the Brazilian sequences are not likely to be closely related
to European D3 sequences. Such results will contribute to further epidemiological and
evolutionary studies of HBV. 相似文献