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81.
Jun Su Hao Zhang Zhihong Li Paolo Ventura Yunju Li Ertao Li Chen Chen Yangping Shen Gang Lian Bing Guo Xinyue Li Liyong Zhang Jianjun He Yaode Sheng Yinji Chen Luohuan Wang Long Zhang Fuqiang Cao Wei Nan Weike Nan Gexing Li Na Song Baoqun Cui Lihua Chen Ruigang Ma Zhicheng Zhang Taoyu Jiao Bingshui Gao Xiaodong Tang Qi Wu Jiaqing Li Liangting Sun Shuo Wang Shengquan Yan Junhui Liao Youbao Wang Sheng Zeng Ding Nan Qiwen Fan Ningchun Qi Wenliang Sun Xuyuan Guo Peng Zhang Yunhua Chen Yong Zhou Jifang Zhou Jinrong He Changsong Shang Mingchuan Li Jianping Cheng Weiping Liu JUNA Collaboration 《科学通报(英文版)》2022,(2):125-132
The 25Mg(p,γ)26Al reaction plays an important role in the study of cosmic 1.809 MeV γ-ray as a signature of ongoing nucleosynthesis in the Galaxy.At astrophysic... 相似文献
82.
Lukas Trixl Thomas Amort Alexandra Wille Manuela Zinni Susanne Ebner Clara Hechenberger Felix Eichin Hanna Gabriel Ines Schoberleitner Anming Huang Paolo Piatti Roxana Nat Jakob Troppmair Alexandra Lusser 《Cellular and molecular life sciences : CMLS》2018,75(8):1483-1497
Chemical modifications of RNA have been attracting increasing interest because of their impact on RNA fate and function. Therefore, the characterization of enzymes catalyzing such modifications is of great importance. The RNA cytosine methyltransferase NSUN3 was recently shown to generate 5-methylcytosine in the anticodon loop of mitochondrial tRNAMet. Further oxidation of this position is required for normal mitochondrial translation and function in human somatic cells. Because embryonic stem cells (ESCs) are less dependent on oxidative phosphorylation than somatic cells, we examined the effects of catalytic inactivation of Nsun3 on self-renewal and differentiation potential of murine ESCs. We demonstrate that Nsun3-mutant cells show strongly reduced mt-tRNAMet methylation and formylation as well as reduced mitochondrial translation and respiration. Despite the lower dependence of ESCs on mitochondrial activity, proliferation of mutant cells was reduced, while pluripotency marker gene expression was not affected. By contrast, ESC differentiation was skewed towards the meso- and endoderm lineages at the expense of neuroectoderm. Wnt3 was overexpressed in early differentiating mutant embryoid bodies and in ESCs, suggesting that impaired mitochondrial function disturbs normal differentiation programs by interfering with cellular signalling pathways. Interestingly, basal levels of reactive oxygen species (ROS) were not altered in ESCs, but Nsun3 inactivation attenuated induction of mitochondrial ROS upon stress, which may affect gene expression programs upon differentiation. Our findings not only characterize Nsun3 as an important regulator of stem cell fate but also provide a model system to study the still incompletely understood interplay of mitochondrial function with stem cell pluripotency and differentiation. 相似文献
83.
Marieke Rienks Anna Papageorgiou Kristiaan Wouters Wouter Verhesen Rick van Leeuwen Paolo Carai Georg Summer Dirk Westermann Stephane Heymans 《Cellular and molecular life sciences : CMLS》2017,74(8):1511-1525
Background
Viral myocarditis can severely damage the myocardium through excessive infiltration of immune cells. Osteoglycin (OGN) is part of the small leucine-rich repeat proteoglycan (SLRP) family. SLRP’s may affect inflammatory and fibrotic processes, but the implication of OGN in cardiac inflammation and the resulting injury upon viral myocarditis is unknown.Methods and results
This study uncovered a previously unidentified 72-kDa variant of OGN that is predominant in cardiac human and mouse samples of viral myocarditis. Its absence in mice significantly decreased cardiac inflammation and injury in Coxsackievirus-B3-induced myocarditis. It also delayed mortality in lipopolysaccharide-induced endotoxemia going along with a reduced systemic production of pro-inflammatory cytokines. This 72-kDa OGN is expressed in the cell membrane of circulating and resident cardiac macrophages and neutrophils. Co-immunoprecipitation and OGN siRNA experiments revealed that this 72-kDa variant activates the toll-like receptor-4 (TLR4) with a concomitant increase in IL-6, TNF-α, IL-1β, and IL-12 expression. This immune cell activation by OGN occurred via MyD88 and increased phosphorylation of c-jun. Finally, the 72-kDa chondroitin sulfate is the result of O-linked glycosylation of the 32-kDa protein core of OGN. In contrast, the 34-kDa dermatan sulfate-OGN, involved in collagen cross linking, was also the result of O-linked glycosylation.Conclusion
The current study discovered a novel 72-kDa chondroitin sulfate-OGN that is specific for innate immune cells. This variant is able to bind and activate TLR4. The absence of OGN decreases cytokine production by both circulating and cardiac leukocytes upon (systemic) LPS exposure, and reduces cardiac inflammation and injury in viral myocarditis.84.
Qiao H He X Schymura D Ban L Field L Dani FR Michelucci E Caputo B della Torre A Iatrou K Zhou JJ Krieger J Pelosi P 《Cellular and molecular life sciences : CMLS》2011,68(10):1799-1813
To understand olfactory discrimination in Anopheles gambiae, we made six purified recombinant OBPs and investigated their ligand-binding properties. All OBPs were expressed in bacteria with additional production of OBP47 in the yeast Kluveromyces lactis. Ligand-binding experiments, performed with a diverse set of organic compounds, revealed marked differences between the OBPs. Using the fluorescent probe N-phenyl-1-naphthylamine, we also measured the binding curves for binary mixtures of OBPs and obtained, in some cases, unexpected behaviour, which could only be explained by the OBPs forming heterodimers with binding characteristics different from those of the component proteins. This shows that OBPs in mosquitoes can form complexes with novel ligand specificities, thus amplifying the repertoire of OBPs and the number of semiochemicals that can be discriminated. Confirmation of the likely role of heterodimers was demonstrated by in situ hybridisation, suggesting that OBP1 and OBP4 are co-expressed in some antennal sensilla of A. gambiae. 相似文献
85.
Anna Maria Frassanito Laura Barsanti Vincenzo Passarelli Valtere Evangelista Paolo Gualtieri 《Cellular and molecular life sciences : CMLS》2010,67(6):965-971
Here, we report the DNA sequence of the rhodopsin gene in the alga Cyanophora paradoxa (Glaucophyta). The primers were designed according to the conserved regions of prokaryotic and eukaryotic rhodopsin-like
proteins deposited in the GenBank. The sequence consists of 1,272 bp comprised of 5 introns. The correspondent protein, named
Cyanophopsin, showed high identity to rhodopsin-like proteins of Archea, Bacteria, Fungi, and Algae. At the N-terminal, the
protein is characterized by a region with no transmembrane α-helices (80 aa), followed by a region with 7α-helices (219 aa)
and a shorter 35-aa C-terminal region. The DNA sequence of the N-terminal region was expressed in E. coli and the recombinant purified peptide was used as antigen in hens to obtain polyclonal antibodies. Indirect immunofluorescence
in C. paradoxa cells showed a marked labeling of the muroplast (aka cyanelle) membrane. 相似文献
86.
Rothman N Garcia-Closas M Chatterjee N Malats N Wu X Figueroa JD Real FX Van Den Berg D Matullo G Baris D Thun M Kiemeney LA Vineis P De Vivo I Albanes D Purdue MP Rafnar T Hildebrandt MA Kiltie AE Cussenot O Golka K Kumar R Taylor JA Mayordomo JI Jacobs KB Kogevinas M Hutchinson A Wang Z Fu YP Prokunina-Olsson L Burdett L Yeager M Wheeler W Tardón A Serra C Carrato A García-Closas R Lloreta J Johnson A Schwenn M Karagas MR Schned A Andriole G Grubb R Black A Jacobs EJ Diver WR Gapstur SM 《Nature genetics》2010,42(11):978-984
We conducted a multi-stage, genome-wide association study of bladder cancer with a primary scan of 591,637 SNPs in 3,532 affected individuals (cases) and 5,120 controls of European descent from five studies followed by a replication strategy, which included 8,382 cases and 48,275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P = 8 × 10?12) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 × 10?11) on 19q12 maps to CCNE1 and rs11892031 (P = 1 × 10??) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P = 4 × 10?11) and a tag SNP for NAT2 acetylation status (P = 4 × 10?11), and found interactions with smoking in both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into the mechanisms of carcinogenesis. 相似文献
87.
Early-stage epigenetic modification during somatic cell reprogramming by Parp1 and Tet2 总被引:1,自引:0,他引:1
CA Doege K Inoue T Yamashita DB Rhee S Travis R Fujita P Guarnieri G Bhagat WB Vanti A Shih RL Levine S Nik EI Chen A Abeliovich 《Nature》2012,488(7413):652-655
88.
Caffau E Bonifacio P François P Sbordone L Monaco L Spite M Spite F Ludwig HG Cayrel R Zaggia S Hammer F Randich S Molaro P Hill V 《Nature》2011,477(7362):67-69
The early Universe had a chemical composition consisting of hydrogen, helium and traces of lithium; almost all other elements were subsequently created in stars and supernovae. The mass fraction of elements more massive than helium, Z, is known as 'metallicity'. A number of very metal-poor stars has been found, some of which have a low iron abundance but are rich in carbon, nitrogen and oxygen. For theoretical reasons and because of an observed absence of stars with Z?1.5?×?10(-5), it has been suggested that low-mass stars cannot form from the primitive interstellar medium until it has been enriched above a critical value of Z, estimated to lie in the range 1.5?×?10(-8) to 1.5?×?10(-6) (ref. 8), although competing theories claiming the contrary do exist. (We use 'low-mass' here to mean a stellar mass of less than 0.8 solar masses, the stars that survive to the present day.) Here we report the chemical composition of a star in the Galactic halo with a very low Z (≤?6.9?×?10(-7), which is 4.5?×?10(-5) times that of the Sun) and a chemical pattern typical of classical extremely metal-poor stars--that is, without enrichment of carbon, nitrogen and oxygen. This shows that low-mass stars can be formed at very low metallicity, that is, below the critical value of Z. Lithium is not detected, suggesting a low-metallicity extension of the previously observed trend in lithium depletion. Such lithium depletion implies that the stellar material must have experienced temperatures above two million kelvin in its history, given that this is necessary to destroy lithium. 相似文献
89.
90.
This paper concerns the cyclical evolution of the Italian economy and, in particular, the role of confidence indicators. In the first part of the paper various confidence indicators, computed according to the European Commission (EC) methodology, are investigated. In particular, the analysis concentrates on the dynamics of some business climate indicators referred to the supply side of the economy (i.e. manufacturing, retail and construction industries). In the second part of the analysis, new confidence indicators exploring the wide informative set characterizing the ISAE business surveys are computed. The ability of these indicators in predicting the short‐term evolution of GDP, here considered as a reference series, is compared with that of the previous EC confidence indicators. Finally, in the third part, some estimates of the relationship between the chosen business confidence indicator and some driving variables are presented. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献