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Dongxin Zhao Zhongxian Huang Jie Liu Li Ma Juan He 《Preparative biochemistry & biotechnology》2013,43(10):914-919
AbstractZinc finger protein ZNF191(243–368), the zinc finger region of ZNF191, is potentially associated with cell proliferation in hepatocellular carninoma. A His-tag expression system was used to express and purify proteins with mutations in the zinc finger 3 of ZNF191(243–368) for analysis of protein properties, structure, and functions. The purification of the His-tag fusion proteins was simpler and faster than that of the ZNF191(243–368) inclusion bodies. The properties and structures of the His-tag fusion mutant proteins were investigated using spectrographic techniques and DNA hydrolysis experiment. The His6-tag system could be used to express ZNF191(243–368). The presence of the His6-tag at the N-terminus of ZNF191(243–368) did not evidently affect its properties and structure. However, the site-directed mutations in zinc finger 3 affected the structure of the protein. The DNA hydrolase activity of His6-ZF-F3/H4 suggested that four histidines in zinc finger 3 might form a structure similar to that of the active center in a hydrolase. This work reports that continuous histidines need to form a certain structure for specific functions, and provides new insights into the design of an artificial nuclease. 相似文献
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Huai Chen Qiuan Zhu Changhui Peng Ning Wu Yanfen Wang Xiuqing Fang Yongheng Gao Dan Zhu Gang Yang Jianqing Tian Xiaoming Kang Shilong Piao Hua Ouyang Wenhua Xiang Zhibin Luo Hong Jiang Xingzhang Song Yao Zhang Guirui Yu Xinquan Zhao Peng Gong Tandong Yao Jianghua Wu 《Global Change Biology》2013,19(10):2940-2955
With a pace of about twice the observed rate of global warming, the temperature on the Qinghai‐Tibetan Plateau (Earth's ‘third pole’) has increased by 0.2 °C per decade over the past 50 years, which results in significant permafrost thawing and glacier retreat. Our review suggested that warming enhanced net primary production and soil respiration, decreased methane (CH4) emissions from wetlands and increased CH4 consumption of meadows, but might increase CH4 emissions from lakes. Warming‐induced permafrost thawing and glaciers melting would also result in substantial emission of old carbon dioxide (CO2) and CH4. Nitrous oxide (N2O) emission was not stimulated by warming itself, but might be slightly enhanced by wetting. However, there are many uncertainties in such biogeochemical cycles under climate change. Human activities (e.g. grazing, land cover changes) further modified the biogeochemical cycles and amplified such uncertainties on the plateau. If the projected warming and wetting continues, the future biogeochemical cycles will be more complicated. So facing research in this field is an ongoing challenge of integrating field observations with process‐based ecosystem models to predict the impacts of future climate change and human activities at various temporal and spatial scales. To reduce the uncertainties and to improve the precision of the predictions of the impacts of climate change and human activities on biogeochemical cycles, efforts should focus on conducting more field observation studies, integrating data within improved models, and developing new knowledge about coupling among carbon, nitrogen, and phosphorus biogeochemical cycles as well as about the role of microbes in these cycles. 相似文献
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Xiaoju He Yinyan He Binrong Xi Jiusheng Zheng Xiaoming Zeng Qinhua Cai Yu OuYang Chen Wang Xiaofei Zhou Huiying Huang Wei Deng Siming Xin Qixiang Huang Huai Liu 《PloS one》2013,8(11)
Background
Long non-coding RNAs (lncRNAs) are an important class of pervasive genes involved in a variety of biological functions. They are aberrantly expressed in many types of diseases. In this study, we aimed to investigate the lncRNA profiles in preeclampsia. Preeclampsia has been observed in patients with molar pregnancy where a fetus is absent, which demonstrate that the placenta is sufficient to cause this condition. Thus, we analyzed the lncRNA profiles in preeclampsia placentas.Methodology/Principal Findings
In this study, we described the lncRNA profiles in six preeclampsia placentas (T) and five normal pregnancy placentas (N) using microarray. With abundant and varied probes accounting for 33,045 LncRNAs in our microarray, 28,443 lncRNAs that were expressed at a specific level were detected. From the data, we found 738 lncRNAs that were differentially expressed (≥1.5-fold-change) among preeclampsia placentas compared with controls. Coding-non-coding gene co-expression networks (CNC network) were constructed based on the correlation analysis between the differentially expressed lncRNAs and mRNAs. According to the CNC network and GO analysis of differentially expressed lncRNAs/mRNAs, we selected three lncRNAs to analyze the relationship between lncRNAs and preeclampsia. LOC391533, LOC284100, and CEACAMP8 were evaluated using qPCR in 40 preeclampsia placentas and 40 controls. These results revealed that three lncRNAs were aberrantly expressed in preeclampsia placentas compared with controls.Conclusions/Significance
Our study is the first study to determine the genome-wide lncRNAs expression patterns in preeclampsia placenta using microarray. These results revealed that clusters of lncRNAs were aberrantly expressed in preeclampsia placenta compared with controls, which indicated that lncRNAs differentially expressed in preeclampsia placenta might play a partial or key role in preeclampsia development. Misregulation of LOC391533, LOC284100, and CEACAMP8 might contribute to the mechanism underlying preeclampsia. Taken together, this study may provide potential targets for the future treatment of preeclampsia and novel insights into preeclampsia biology. 相似文献8.
Wei‐Guang Wang Zhao‐Yuan Wu Rui Chen Hai‐Zhou Li Hong‐Mei Li Yuan‐Dan Li Rong‐Tao Li Huai‐Rong Luo 《化学与生物多样性》2013,10(6):1061-1071
Four highly acylated diterpenoids, designated as pierisformotoxins A–D ( 1 – 4 , resp.), along with 26 known compounds, were isolated from the flowers of Pieris formosa. Among them, pierisformotoxins A and B ( 1 and 2 , resp.) were new highly acylated grayanane diterpenoids, of which the five‐membered ring A has undergone an oxidative cleavage between C(3) and C(4), followed by lactonization, to give rise to a five‐membered lactone ring between C(3) and C(5), differing from the previously reported grayanane diterpenoids with a 5/7/6/5 ring system. Results of the cAMP‐regulation‐activity assay showed that pierisformotoxin C ( 3 ) at 10 μM (inhibitory ratio (IR): 10.1%) or 2 μM (9.8%), and pierisformotoxin B ( 2 ) at 50 μM (13.9%) significantly decreased the cAMP level in N1E‐115 neuroblastoma cells (p<0.05). 相似文献
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Di Yan Li Long Zhang Ming Yao Yang Huai Liang Xu Hua Dong Yin Ying Li Qing Zhu 《Molecular biology reports》2013,40(12):7111-7116
Luteinizing hormone/choriogonadotropin receptor (LHCGR) gene, potentially related to reproductive traits in chickens, was genotyped by using the Pooled DNA Sequencing, PCR–SSCP and Directing Sequencing techniques. 306 Erlang Mountain chickens form one line (SD03, a line that has been selected for egg quality from a local chicken breed in Sichuan province, China) were genotyped in this study. The associations between LHCGR polymorphisms and six reproductive traits [body weight at first egg (BWAFE), weight of first egg, age at first egg (AFE), number of eggs at 300 days of age (EN), body weight at 300 days of age and egg weight at 300 days of age (EWTA)] were estimated using the one-way analysis of variance method. Results showed that SNP +G4058A and SNP +T4099G of the LHCGR gene were significantly associated with BWFE and AFE. Birds with the AG genotype for the +G4058A SNP exhibited shorter AFE (P < 0.05) and greater EN than those of the GG and AA genotypes, suggesting a balancing selection (overdominance); the effect of allele C in SNP +C3021T and allele C in SNP +T4490C on EN and AFE is additive and may reflect the influence of positive selection. These alleles have promise as genetic markers for future marker-assisted selection. 相似文献