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961.
Meng-Ze Du Feng-Biao Guo Yue-Yun Chen 《Journal of biomolecular structure & dynamics》2013,31(2):391-401
Abstract In this paper, we re-annotated the genome of Pyrobaculum aerophilum str. IM2, particularly for hypothetical ORFs. The annotation process includes three parts. Firstly and most importantly, 23 new genes, which were missed in the original annotation, are found by combining similarity search and the ab initio gene finding approaches. Among these new genes, five have significant similarities with function-known genes and the rest have significant similarities with hypothetical ORFs contained in other genomes. Secondly, the coding potentials of the 1645 hypothetical ORFs are re-predicted by using 33 Z curve variables combined with Fisher linear discrimination method. With the accuracy being 99.68%, 25 originally annotated hypothetical ORFs are recognized as non-coding by our method. Thirdly, 80 hypothetical ORFs are assigned with potential functions by using similarity search with BLAST program. Re-annotation of the genome will benefit related researches on this hyperthermophilic crenarchaeon. Also, the re-annotation procedure could be taken as a reference for other archaeal genomes. Details of the revised annotation are freely available at http://cobi.uestc.edu.cn/resource/paero/ 相似文献
962.
Xiao‐Jun Guan Lin Song Feng‐Feng Han Zhi‐Lei Cui Xi Chen Xue‐Jun Guo Wei‐Guo Xu 《Journal of cellular biochemistry》2013,114(2):323-335
Progressive pulmonary inflammation and emphysema have been implicated in the progression of chronic obstructive pulmonary disease (COPD), while current pharmacological treatments are not effective. Transplantation of bone marrow mesenchymal stem cells (MSCs) has been identified as one such possible strategy for treatment of lung diseases including acute lung injury (ALI) and pulmonary fibrosis. However, their role in COPD still requires further investigation. The aim of this study is to test the effect of administration of rat MSCs (rMSCs) on emphysema and pulmonary function. To accomplish this study, the rats were exposed to cigarette smoke (CS) for 11 weeks, followed by administration of rMSCs into the lungs. Here we show that rMSCs infusion mediates a down‐regulation of pro‐inflammatory mediators (TNF‐α, IL‐1β, MCP‐1, and IL‐6) and proteases (MMP9 and MMP12) in lung, an up‐regulation of vascular endothelial growth factor (VEGF), VEGF receptor 2, and transforming growth factor (TGFβ‐1), while reducing pulmonary cell apoptosis. More importantly, rMSCs administration improves emphysema and destructive pulmonary function induced by CS exposure. In vitro co‐culture system study of human umbilical endothelial vein cells (EA.hy926) and human MSCs (hMSCs) provides the evidence that hMSCs mediates an anti‐apoptosis effect, which partly depends on an up‐regulation of VEGF. These findings suggest that MSCs have a therapeutic potential in emphysematous rats by suppressing the inflammatory response, excessive protease expression, and cell apoptosis, as well as up‐regulating VEGF, VEGF receptor 2, and TGFβ‐1. J. Cell. Biochem. 114: 323–335, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
963.
Wei Guo Dong Ren Xiuting Chen Xiang'an Tu Shuai Huang Min Wang Libing Song Xuenong Zou Xinsheng Peng 《Journal of cellular biochemistry》2013,114(7):1606-1615
The principal problem arising from prostate cancer (PCa) is its propensity to metastasize to bones, and it's crucial to understand the mechanism of tumor progression to metastasis in order to develop therapies that may reduce the morbidity and mortality of PCa patients. Although we had identified that microRNA(miR)‐145 could repress bone metastasis of PCa via regulating epithelial–mesenchymal transition (EMT) in previous study, it is still unknown how miR‐145 regulated EMT. In the present study, we constructed a luciferase reporter system and identified HEF1 as a direct target of miR‐145. More importantly, HEF1 was shown to promote migration, invasion and EMT of PC‐3 cells, a human PCa cell line originated from a bone metastatic PCa specimen. And HEF1 was also shown to partially mediate miR‐145 suppression of EMT and invasion. Furthermore, inhibition of HEF1 repressed bone invasion of PC‐3 cells in vivo. Expression of HEF1 was negatively correlated with miR‐145 in primary PCa and bone metastatic specimens, but HEF1 was higher in samples which were more likely to commit to bone metastasis or those with higher free prostate‐specific antigen (fPSA) levels and Gleason scores. Taken together, these findings indicate that HEF1 promotes EMT and bone invasion in prostate cancer by directly targeted by miR‐145, and miR‐145 suppresses EMT and invasion, at least in part, through repressing HEF1. J. Cell. Biochem. 114: 1606–1615, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
964.
Chuan-yu Guo Guang-heng Wu Jin Xing Wen-qi Li Ding-zhong Tang Bai-ming Cui 《Plant cell reports》2013,32(5):687-702
Key message
A gene encoding a coproporphyrinogen III oxidase mediates disease resistance in plants by the salicylic acid pathway.Abstract
A number of genes that regulate powdery mildew resistance have been identified in Arabidopsis, such as ENHANCED DISEASE RESISTANCE 1 to 3 (EDR1 to 3). To further study the molecular interactions between the powdery mildew pathogen and Arabidopsis, we isolated and characterized a mutant that exhibited enhanced resistance to powdery mildew. The mutant also showed dramatic powdery mildew-induced cell death as well as growth defects and early senescence in the absence of pathogens. We identified the affected gene by map-based cloning and found that the gene encodes a coproporphyrinogen III oxidase, a key enzyme in the tetrapyrrole biosynthesis pathway, previously known as LESION INITIATION 2 (LIN2). Therefore, we designated the mutant lin2-2. Further studies revealed that the lin2-2 mutant also displayed enhanced resistance to Hyaloperonospora arabidopsidis (H.a.) Noco2. Genetic analysis showed that the lin2-2-mediated disease resistance and spontaneous cell death were dependent on PHYTOALEXIN DEFICIENT 4 (PAD4), SALICYLIC ACID INDUCTION-DEFICIENT 2 (SID2), and NONEXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1), which are all involved in salicylic acid signaling. Furthermore, the relative expression levels of defense-related genes were induced after powdery mildew infection in the lin2-2 mutant. These data indicated that LIN2 plays an important role in cell death control and defense responses in plants. 相似文献965.
966.
967.
Estrogen receptor α (ERα) may play important roles in many estrogen physiological effects, but little is known about the fluctuation of ERα during the estrous cycle. In this study, the dynamic expression of ERα mRNA and protein in periodontal tissue during the estrous cycle were examined. Forty 12‐week‐old female rats were divided into four groups, based on the estrous cycle stage, and sacrificed. Immunohistochemistry and in situ hybridization were used to detect dynamic changes in ERα protein and mRNA in periodontal tissue during the estrous cycle, and data were analyzed by one‐way ANOVA and cosinor analysis for temporal patterns. Significant differences (p<0.05) were found in the expression of ERα protein and mRNA among the four groups. The expression of ERα protein and mRNA exhibited an infradian rhythm with a period of about 120 h (five days). The phase and amplitude differences between ERα protein and mRNA were not significant (p>0.05). The results suggest the expression of ERα is dynamic during the estrous cycle and that in the future chronobiologic methods should be used to study the mechanism of estrogen effect on periodontal tissue. 相似文献
968.
969.
Chanjuan Guo Judy Simon Rainer Gasche Pascale Sarah Naumann Carolin Bimüller Rodica Pena Andrea Polle Ingrid Kögel-Knabner Bernd Zeller Heinz Rennenberg Michael Dannenmann 《Plant and Soil》2013,369(1-2):657-668
Aims
Our aims were to characterize the fate of leaf-litter-derived nitrogen in the plant-soil-microbe system of a temperate beech forest of Southern Germany and to identify its importance for N nutrition of beech seedlings.Methods
15N-labelled leaf litter was traced in situ into abiotic and biotic N pools in mineral soil as well as into beech seedlings and mycorrhizal root tips over three growing seasons.Results
There was a rapid transfer of 15N into the mineral soil already 21 days after tracer application with soil microbial biomass initially representing the dominant litter-N sink. However, 15N recovery in non-extractable soil N pools strongly increased over time and subsequently became the dominant 15N sink. Recovery in plant biomass accounted for only 0.025 % of 15N excess after 876 days. After three growing seasons, 15N excess recovery was characterized by the following sequence: non-extractable soil N?>>?extractable soil N including microbial biomass?>>?plant biomass?>?ectomycorrhizal root tips.Conclusions
After quick vertical dislocation and cycling through microbial N pools, there was a rapid stabilization of leaf-litter-derived N in non-extractable N pools of the mineral soil. Very low 15N recovery in beech seedlings suggests a high importance of other N sources such as root litter for N nutrition of beech understorey. 相似文献970.
Yifu Yuan Weihua Guo Wenjuan Ding Ning Du Yujie Luo Jian Liu Fei Xu Renqing Wang 《Plant and Soil》2013,366(1-2):389-400