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951.
Background
Protein synthetic lethal genetic interactions are useful to define functional relationships between proteins and pathways. However, the molecular mechanism of synthetic lethal genetic interactions remains unclear.Results
In this study we used the clusters of short polypeptide sequences, which are typically shorter than the classically defined protein domains, to characterize the functionalities of proteins. We developed a framework to identify significant short polypeptide clusters from yeast protein sequences, and then used these short polypeptide clusters as features to predict yeast synthetic lethal genetic interactions. The short polypeptide clusters based approach provides much higher coverage for predicting yeast synthetic lethal genetic interactions. Evaluation using experimental data sets showed that the short polypeptide clusters based approach is superior to the previous protein domain based one.Conclusion
We were able to achieve higher performance in yeast synthetic lethal genetic interactions prediction using short polypeptide clusters as features. Our study suggests that the short polypeptide cluster may help better understand the functionalities of proteins.952.
Alteration of Components of Leaf Water Potential and Water Content in Velvetleaf under the Effects of Long-Term Humidity Difference 总被引:1,自引:0,他引:1 下载免费PDF全文
Velvetleaf (Abutilon theophrasti Medik.) was grown in growth chambers set at 45 or 85% relative humidity at 30°C, CO2 350 microliters per liter and 1000 micromoles per square meter per second of photosynthetically active radiation. Soil water potential was maintained at −0.05 megapascal by subirrigation with half strength Hoagland solution. The third, fourth, and fifth leaves from the base of 21- and 25-day-old plants were used for pressure-volume measurements. Components of leaf water status including water potential (osmotic and potential associated with the apoplast), leaf water content (apoplasmic and symplasmic water), and elastic modulus of leaf tissue were determined. Results indicate: (a) persistent dry air generated leaves with lower water potential at a given relative water content than did humid air; (b) the higher total leaf water content in plants grown in dry air was related to an increase in apoplasmic water, whereas symplasmic water remained similar in both humidity treatments; (c) difference in leaf water potential between low and high humidity treatments was related to decreased potential associated with the apoplast but not to a change in cell wall elasticity. 相似文献
953.
Liming Yan Yiqi Luo Rebecca A. Sherry Jesse E. Bell Xuhui Zhou Jianyang Xia 《Global Change Biology Bioenergy》2014,6(5):556-565
The efficiency of a terrestrial ecosystem to use rainfall in production is critical in regulating the ecological functions of the earth system under global change. However, it remains unclear how rain use efficiency (RUE) will be altered by changes in climate and human activities such as biofuel harvest. In this study, we used RUE data from a long‐term experiment in a tallgrass prairie to analyze the effects of warming and biofuel harvest (clipping). From 2000 to 2011, experimental warming enhanced RUE in most years, with larger positive effects in normal and wet than dry hydrological years. Clipping decreased RUE in dry and normal hydrological years, but had no impact on RUE in wet years. The observed RUE responses resulted from treatment‐induced changes in both biologically ineffective (i.e., runoff and soil evaporation) and effective (i.e., transpiration) parts of precipitation. For example, litter cover was increased in warming plots, but reduced by clipping, leading to negative and positive effects on runoff and soil evaporation, respectively. The dominance of C4 species, which usually have higher water use efficiency than C3 species, was enhanced by warming, but reduced by clipping. Moreover, RUE was positively correlated with ratios of rainfall in the late growing season (June–August), when the growth of C4 plants was most active, relative to that in the other seasons. Our results indicate that RUE is positively influenced by climate warming, but negatively affected by biofuel harvest in tallgrass prairie of the Great Plains. These findings highlight the important roles of plant community structure and temporal distribution of precipitation in regulating ecosystem RUE. 相似文献
954.
Yong Liu Yuan-hui Liu Ning Tan Ji-yan Chen Ying-ling Zhou Li-wen Li Chong-yang Duan Ping-Yan Chen Jian-fang Luo Hua-long Li Wei-Guo 《PloS one》2014,9(10)
Objectives
We prospectively compared the preventive effects of rosuvastatin and atorvastatin on contrast-induced nephropathy (CIN) in patients with chronic kidney disease (CKD) undergoing percutaneous coronary intervention (PCI).Methods
We enrolled 1078 consecutive patients with CKD undergoing elective PCI. Patients in Group 1 (n = 273) received rosuvastatin (10 mg), and those in group 2 (n = 805) received atorvastatin (20 mg). The primary end-point was the development of CIN, defined as an absolute increase in serum creatinine ≥0.5 mg/dL, or an increase ≥25% from baseline within 48–72 h after contrast medium exposure.Results
CIN was observed in 58 (5.4%) patients. The incidence of CIN was similar in patients pretreated with either rosuvastatin or atorvastatin (5.9% vs. 5.2%, p = 0.684). The same results were also observed when using other definitions of CIN. Clinical and procedural characteristics did not show significant differences between the two groups (p>0.05). Additionally, there were no significant inter-group differences with respect to in-hospital mortality rates (0.4% vs. 1.5%, p = 0.141), or other in-hospital complications. Multivariate logistic regression analysis revealed that rosuvastatin and atorvastatin demonstrated similar efficacies for preventing CIN, after adjusting for potential confounding risk factors (odds ratio = 1.17, 95% confidence interval, 0.62–2.20, p = 0.623). A Kaplan–Meier survival analysis showed that patients taking either rosuvastatin or atorvastatin had similar incidences of all-cause mortality (9.4% vs. 7.1%, respectively; p = 0.290) and major adverse cardiovascular events (29.32% vs. 23.14%, respectively; p = 0.135) during follow-up.Conclusions
Rosuvastatin and atorvastatin have similar efficacies for preventing CIN in patients with CKD undergoing PCI. 相似文献955.
热性癫痫发作是儿童常见病,能损害认知功能,而突触可塑性和再可塑性(metaplasticity)是维系大脑认知功能的重要神经基础.本文通过脑片灌流和细胞外场电位记录术研究了热性癫痫发作大鼠海马齿状回外侧支的突触可塑性和再可塑性.制作对照组和热性癫痫发作组大鼠的脑切片后,记录电极置于齿状回外侧支的外分子层获取兴奋性突触后... 相似文献
956.
Dan-dan Li Bin-wu Zhong Hai-xia Zhang Hong-yan Zhou Jie Luo Yang Liu Gui-chun Xu Chun-sheng Luan Jun Fang 《Molecular biology reports》2016,43(10):1079-1087
The degeneration of retinal pigment epithelium (RPE) cells in the sub retinal pigment epithelial space and choroid is an initial pathological characteristic for the age-related macular degeneration which is the leading cause of severe vision loss in old people. Moreover, oxidative stress is implicated as a major inducer of RPE cell death. Here, we assessed the correlation between the H2O2-induced RPE cell death and glutamine metabolism. We found under low glutamine supply (20 %), the ARPE-19 cells were more susceptive to H2O2-induced apoptosis. Moreover, the glutamine uptake and the glutaminase (GLS) were suppressed by H2O2 treatments. Moreover, we observed miR-23a was upregulated by H2O2 treatments and overexpression of miR-23a significantly sensitized ARPE-19 cells to H2O2. Importantly, Western blotting and luciferase assay demonstrated GLS1 is a direct target of miR-23a in RPE cells. Inhibition of the H2O2-induced miR-23a by antagomiR protected the RPE cells from the oxidative stress-induced cell death. In addition, recovery of GLS1 expression in miR-23a overexpressed RPE cells rescued the H2O2-induced cell death. This study illustrated a mechanism for the protection of the oxidative-induced RPE cell death through the recovery of glutamine metabolism by inhibition of miR-23a, contributing to the discovery of novel targets and the developments of therapeutic strategies for the prevention of RPE cells from oxidative stress. 相似文献
957.
Ku70 plays an important role in the DSBR (DNA double-strand breaks repair) and maintenance of genomic integrity. Genetic variations
within human Ku70 have been demonstrated to be associated with increased risk of several types of cancers. In this hospital-based
case–control study, we aimed to investigate whether a single nucleotide polymorphism (SNP) in the promoter region (rs2267437)
of Ku70 gene is associated with susceptibility to breast cancer in Chinese Han population. A total of 293 patients with breast
cancer and 301 age-matched healthy controls were enrolled in this study. The Ku70 −1310C/G polymorphism was determined by
polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) analysis. A significant difference in genotype
distribution and allele frequency was observed between patients and controls. The CG or GG carries were at higher risk of
breast cancer compared with the CC homozygotes (OR = 1.43, 95% CI = 1.02–2.00, P = 0.038 and OR = 3.53, 95% CI = 1.60–7.80, P = 0.002, respectively). Further stratification analysis revealed that G allele was associated with an increased risk of breast
cancer among premenopausal women (OR = 1.68, 95% CI = 1.21–2.33, P = 0.002), but not in postmenopausal women (OR = 1.33, 5% CI = 0.85–2.10, P = 0.216). Our study suggests that the Ku70 −1310C/G promoter polymorphism may be a susceptibility factor for breast cancer
in Chinese Han population. 相似文献
958.
Sánchez-Martínez A Luo N Clemente P Adán C Hernández-Sierra R Ochoa P Fernández-Moreno MA Kaguni LS Garesse R 《Biochimica et biophysica acta》2006,1757(9-10):1190-1198
Human mitochondrial diseases are associated with a wide range of clinical symptoms, and those that result from mutations in mitochondrial DNA affect at least 1 in 8500 individuals. The development of animal models that reproduce the variety of symptoms associated with this group of complex human disorders is a major focus of current research. Drosophila represents an attractive model, in large part because of its short life cycle, the availability of a number of powerful techniques to alter gene structure and regulation, and the presence of orthologs of many human disease genes. We describe here Drosophila models of mitochondrial DNA depletion, deafness, encephalopathy, Freidreich's ataxia, and diseases due to mitochondrial DNA mutations. We also describe several genetic approaches for gene manipulation in flies, including the recently developed method of targeted mutagenesis by recombinational knock-in. 相似文献
959.
本文用一氧化氮合酶(NOS)的组织化学方法对胎龄15周至36周的人胎视网膜含NOS神经元的发育进行了研究。胚胎15周视网膜颞侧半少部分神经元即有NOS的表达,20周视网膜含NOS神经元数密度达峰值。大部分含NOS神经元胞体位于内核层内带,只少部分位于节细胞层,其突起均分布于内同层,形成内同层的1、3、5亚层。含NOS神经元的形态各异,依据其突起的多少分Ⅰ、Ⅱ、Ⅲ等三种类型,其中Ⅱ、Ⅲ型含NOS神经元在28周以后才开始出现,且愈近晚期胎龄,它们所占含NOS神经元的数量比呈上升趋势。随视网膜发育成熟,含NOS神经元胞体均面积呈不断增大的变化。本文结果显示:人胎视网膜内核层含NOS神经元为无长突细胞,节细胞层的Ⅰ型含NOS神经元为移位无长突细胞,推测它们在视网膜的发育过程中对内网层突触的形成与修饰可能起有重要作用。 相似文献
960.
Yaoming Li Wangwang Lv Lili Jiang Lirong Zhang Shiping Wang Qi Wang Kai Xue Bowen Li Peipei Liu Huan Hong Wangmu Renzen A Wang Caiyun Luo Zhenhua Zhang Tsechoe Dorji Neslihan Ta Zhezhen Wang Huakun Zhou Yanfen Wang 《Global Change Biology》2019,25(10):3438-3449
Changes in labile carbon (LC) pools and microbial communities are the primary factors controlling soil heterotrophic respiration (Rh) in warming experiments. Warming is expected to initially increase Rh but studies show this increase may not be continuous or sustained. Specifically, LC and soil microbiome have been shown to contribute to the effect of extended warming on Rh. However, their relative contribution is unclear and this gap in knowledge causes considerable uncertainty in the prediction of carbon cycle feedbacks to climate change. In this study, we used a two‐step incubation approach to reveal the relative contribution of LC limitation and soil microbial community responses in attenuating the effect that extended warming has on Rh. Soil samples from three Tibetan ecosystems—an alpine meadow (AM), alpine steppe (AS), and desert steppe (DS)—were exposed to a temperature gradient of 5–25°C. After an initial incubation period, soils were processed in one of two methods: (a) soils were sterilized then inoculated with parent soil microbes to assess the LC limitation effects, while controlling for microbial community responses; or (b) soil microbes from the incubations were used to inoculate sterilized parent soils to assess the microbial community effects, while controlling for LC limitation. We found both LC limitation and microbial community responses led to significant declines in Rh by 37% and 30%, respectively, but their relative contributions were ecosystem specific. LC limitation alone caused a greater Rh decrease for DS soils than AMs or ASs. Our study demonstrates that soil carbon loss due to Rh in Tibetan alpine soils—especially in copiotrophic soils—will be weakened by microbial community responses under short‐term warming. 相似文献