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81.
Molecular diversity of bacteria in Yunnan yellow cattle (Bos taurs) from Nujiang region, China 总被引:1,自引:0,他引:1
Leng J Cheng YM Zhang CY Zhu RJ Yang SL Gou X Deng WD Mao HM 《Molecular biology reports》2012,39(2):1181-1192
The rumen content of four Yunnan Yellow Cattle (Bos taurs) were collected to determine the bacteria diversity by using 16S rRNA gene sequence analysis. A total of 129 sequences were
examined and the sequences were referred as 107 OTU (Operational Taxonomy Unit) according to the similarity level of 97% in
gene sequence. Similarity analysis revealed that Yunnan Yellow Cattle had 12 sequences (10 OTU) shared 97% or greater similarity
with cultured rumen bacteria Butyrivibrio fibrisolvens, Succiniclasticum ruminis, Ruminococcus bromii, Clostridium proteoclasticum, Ruminococcus flavefaciens, Pseudobutyrivibrio ruminis, Jeotgalicoccus psychrophilus, and Prevotella ruminicola, which accounting for 9.3% of the total clones (9.2% of the total OTU). The further 12 sequences (9 OTU) shared 90–97% similarity
with cultured bacteria Clostridium aminobutyricum, butyrate-producing bacterium, Schwartzia succinivorans, Prevotella ruminicola, Eubacterium ruminantium, Ruminococcus albus, and Clostridium termitidis, also accounting for 9.3% of the total sequences (8.3% of the total OTU). The remaining 105 sequences (90 OTU) shared less
than 90% similarity with cultured bacteria, accounting for 81.4% of the total sequences (82.5% of the total OTU). According
to the phylogenetic analysis, all sequences were phylogenetically placed within phyla of low G+C subdivision (accounting for
72.1 and 72.5% of the total clones and OTU, respectively) and CFB subdivision (Cytophaga-Flexibacter-Bacteroides; accounting for 27.9 and 27.5% of the total clones and OTU, respectively). Among the examined clones, rare bacteria Jeotgalicoccus psychrophilus was detected in the rumen of cattle. 相似文献
82.
Aizawa R Yamada A Suzuki D Iimura T Kassai H Harada T Tsukasaki M Yamamoto G Tachikawa T Nakao K Yamamoto M Yamaguchi A Aiba A Kamijo R 《Mechanisms of development》2012,129(1-4):38-50
Cdc42, a member of the Rho subfamily of small GTPases, is known to be a regulator of multiple cellular functions, including cytoskeletal organization, cell migration, proliferation, and apoptosis. However, its tissue-specific roles, especially in mammalian limb development, remain unclear. To investigate the physiological function of Cdc42 during limb development, we generated limb bud mesenchyme-specific inactivated Cdc42 (Cdc42(fl/fl); Prx1-Cre) mice. Cdc42(fl/fl); Prx1-Cre mice demonstrated short limbs and body, abnormal calcification of the cranium, cleft palate, disruption of the xiphoid process, and syndactyly. Severe defects were also found in long bone growth plate cartilage, characterized by loss of columnar organization of chondrocytes, and thickening and massive accumulation of hypertrophic chondrocytes, resulting in delayed endochondral bone formation associated with reduced bone growth. In situ hybridization analysis revealed that expressions of Col10 and Mmp13 were reduced in non-resorbed hypertrophic cartilage, indicating that deletion of Cdc42 inhibited their terminal differentiation. Syndactyly in Cdc42(fl/fl); Prx1-Cre mice was caused by fusion of metacarpals and a failure of interdigital programmed cell death (ID-PCD). Whole mount in situ hybridization analysis of limb buds showed that the expression patterns of Sox9 were ectopic, while those of Bmp2, Msx1, and Msx2, known to promote apoptosis in the interdigital mesenchyme, were down-regulated. These results demonstrate that Cdc42 is essential for chondrogenesis and ID-PCD during limb development. 相似文献
83.
Keyan Fang Xiaohua Gou Fahu Chen Edward Cook Jinbao Li Yingjun Li 《Trees - Structure and Function》2012,26(5):1471-1481
Understanding spatiotemporal tree growth variability and its associations with climate can provide key insights into forest dynamics in the context of global climate change. Here, we conduct a comprehensive investigation on 64 ring-width chronologies across the entire Northwest (NW) China to understand the regional patterns of tree growth and climate–growth relationships. Using rotated principal component analysis and hierarchical clustering analysis, we found that tree growth was mainly determined by the climate and could be classified into nine groups. Most of the tree-ring chronologies in NW China showed high correlations with moisture conditions in the current and previous growing seasons. After removing age-related growth trends, inter-annual tree growth patterns are supposed to be mainly determined by climate and climate–growth relationships. Since climate–growth relationships for most tree-ring chronologies in this arid region are similar, patterns of tree growth are mainly determined by climate variability. Within each group, the strength of the common signal increases under extreme climate conditions. Thus, climate plays a more important role in determining tree growth in extreme climate conditions relative to the non-climate factors, leading to more coherent growth patterns. 相似文献
84.
Kuan-Yi Lu Sheng-Ce Tao Tzu-Ching Yang Yu-Hsuan Ho Chia-Hsien Lee Chen-Ching Lin Hsueh-Fen Juan Hsuan-Cheng Huang Chin-Yu Yang Ming-Shuo Chen Yu-Yi Lin Jin-Ying Lu Heng Zhu Chien-Sheng Chen 《Molecular & cellular proteomics : MCP》2012,11(11):1177-1190
Fluorescent liposomal nanovesicles (liposomes) are commonly used for lipid research and/or signal enhancement. However, the problem of self-quenching with conventional fluorescent liposomes limits their applications because these liposomes must be lysed to detect the fluorescent signals. Here, we developed a nonquenched fluorescent (NQF)1 liposome by optimizing the proportion of sulforhodamine B (SRB) encapsulant and lissamine rhodamine B-dipalmitoyl phosphatidylethanol (LRB-DPPE) on a liposomal surface for signal amplification. Our study showed that 0.3% of LRB-DPPE with 200 μm of SRB provided the maximal fluorescent signal without the need to lyse the liposomes. We also observed that the NQF liposomes largely eliminated self-quenching effects and produced greatly enhanced signals than SRB-only liposomes by 5.3-fold. To show their application in proteomics research, we constructed NQF liposomes that contained phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) and profiled its protein interactome using a yeast proteome microarray. Our profiling led to the identification of 162 PI(3,5)P2-specific binding proteins (PI(3,5)P2-BPs). We not only recovered many proteins that possessed known PI(3,5)P2-binding domains, but we also found two unknown Pfam domains (Pfam-B_8509 and Pfam-B_10446) that were enriched in our dataset. The validation of many newly discovered PI(3,5)P2-BPs was performed using a bead-based affinity assay. Further bioinformatics analyses revealed that the functional roles of 22 PI(3,5)P2-BPs were similar to those associated with PI(3,5)P2, including vesicle-mediated transport, GTPase, cytoskeleton, and kinase. Among the 162 PI(3,5)P2-BPs, we found a novel motif, HRDIKP[ES]NJLL that showed statistical significance. A docking simulation showed that PI(3,5)P2 interacted primarily with lysine or arginine side chains of the newly identified PI(3,5)P2-binding kinases. Our study showed that this new tool would greatly benefit profiling lipid–protein interactions in high-throughput studies.Cell viability and physiological functions are maintained through a complex biomolecular interaction network. One of the key components in the regulatory system includes lipid–protein interactions that mediate various cell responses and metabolisms. Increasing evidence shows that such interactions have profound influences on cell polarization, the cell cycle, and other cellular processes. To date, in vitro characterizations of lipid interactions with other biomolecules are often conducted using artificial membrane models, such as liposomal nanovesicles, to mimic biological membranes. Liposomal nanovesicles, termed liposomes, are spherical vesicles that are surrounded by phospholipid bilayers in which the lipid of interest can be incorporated. An important benefit of liposomes is the ease in which a large number of fluorescent molecules can be encapsulated so that the liposome binding signals can be greatly enhanced for detection (1–4). Therefore, liposomes have become a practical and popular tool for use as a model membrane or fluorophore-loaded vehicle to study signal amplification (1–4) and/or lipid research (5–9).In general, liposomes are capable of encapsulating hundreds of millions of fluorescent dye molecules, thereby providing greatly enhanced signals (1–4). However, high concentrations of fluorophores often lead to self-quenching, and as a result, the fluorescent signals cannot be detected without first lysing the liposomes (1–4). This issue has limited their applications for real-time detection and high-density chip assays. To solve this problem, we developed a novel non-quenched fluorescent (NQF) liposome with the capability of signal amplification. During the fabrication procedure, we used sulforhodamine B (SRB) as an encapsulant and incorporated lissamine rhodamine B-dipalmitoyl phosphatidylethanol (LRB-DPPE) within the liposomal bilayer.Profiling phosphatidylinositide-protein interactions is of particular interest because these lipids have been implicated in a wide variety of cell functions, including cell signaling, actin cytoskeletal reorganization, exocytosis, and intracellular trafficking (10–14). Among the phosphatidylinositides, phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) is one of the most important mediators of signal transduction (15, 16). Intensive studies over the past decade have shown that PI(3,5)P2 is involved in protein sorting into multivesicular bodies (MVBs), membrane recycling/turnover, and the vacuole acidification (17–19). Like other phosphatidylinositides, PI(3,5)P2 may regulate downstream pathways through the binding of the myo-inositol head group to proteins containing phosphoinositide-binding domains (20, 21). Thus far, a handful of modular phosphoinositide-binding domains have been identified, including C2 (Protein Kinase C homology 2) (22), a WD-40 motif (tryptophan-aspartic acid repeats) that folds as β-propellers (23), ARRB1 (β-arrestin 1), and a number of actin regulatory domains (e.g. the gelsolin/villin family, cofilin, and profilin) (20).To globally profile PI(3,5)P2-binding proteins as the foundation for a better understanding of the biology of PI(3,5)P2, we employed the newly developed PI(3,5)P2-NQF liposomes to probe the Saccharomyces cerevisiae proteome microarray. We not only recovered many proteins that contained known PI(3,5)P2-binding domains, but we also validated many newly discovered PI(3,5)P2-binding proteins using a bead-based affinity assay. Representing both a signal and an analyte carrier, the NQF liposomes should provide a new research model for studying lipid–protein interactions in the future. 相似文献
85.
Heymann MF Herisson F Davaine JM Charrier C Battaglia S Passuti N Lambert G Gouëffic Y Heymann D 《Cytokine》2012,58(2):300-306
Recent works demonstrated the difference of calcification genesis between carotid and femoral plaques, femoral plaques being more calcified. It has been clearly demonstrated that the molecular triad osteoprotegerin (OPG)/Receptor Activator of NFkB (RANK)/RANK Ligand (RANKL) exerts its activities in the osteoimmunology and vascular system. The aim of this study was to determine their expression and their potential role in calcifications of the atheromatous plaques located in two different peripheral arterial beds, carotid and femoral. The expression of OPG, RANK and RANKL was analyzed by immunochemistry in 40 carotid and femoral samples. Blood OPG and RANKL were quantified using specific ELISA assays. OPG staining was more frequently observed in carotid than in femoral plaques, especially in lipid core. Its expression correlated with macrophage infiltration more abundantly observed in carotid specimens. Surprisingly, serum OPG concentration was significantly lower in carotid population compared to femoral population while RANK and RANKL were equally expressed in both arterial beds. Carotid plaques that are less rich in calcium than femoral specimens, express more frequently OPG, this expression being correlated with the abundance of macrophages in the lesions. These data strengthen the key role played by OPG in the differential calcification in carotid and femoral plaques. 相似文献
86.
Keyan Fang Xiaohua Gou Fahu Chen Yingjun Li Fen Zhang Miklos Kazmer 《Dendrochronologia》2012,30(2):113-119
Individual tree-ring series may show changed growth trends and divergent climate–growth associations even within a site, highlighting the need to examine tree growth and its climate association before building a chronology. We provided a case study for the stratification and temporal variability of tree growth and its climate associations of individual cores for three mountain ranges in north central China. Tree growth is mainly limited by moisture conditions in previous July–September and current June–August. Repeated sampling and field investigations of Picea wilsonii at Xinglong Mountain over a growth year of 2004 suggested that the growing season is from about the end of April to the end of September. It appears that the moisture conditions in previous and current growing seasons are crucial for tree growth in this region. However, a decrease in drought limitation was observed for a few tree-ring series. We thereby built the pooled chronology and sub-site chronologies with only drought-sensitive tree rings similar climate–growth relationships from the three mountain slopes. Growth disturbances of tree-ring series are detected by checking the occurrence of successively low values of the biweight series, which are treated by fitting a flexible curve. 相似文献
87.
Weiyang He Qiong Wang Jennings Xu Xiuling Xu Mabel T. Padilla Guosheng Ren Xin Gou Yong Lin 《Autophagy》2012,8(12):1811-1821
Although it is known that tumor necrosis factor-related apoptosis-inducing ligand (TNFSF10/TRAIL) induces autophagy, the mechanism by which autophagy is activated by TNFSF10 is still elusive. In this report, we show evidence that TRAF2- and RIPK1-mediated MAPK8/JNK activation is required for TNFSF10-induced cytoprotective autophagy. TNFSF10 activated autophagy rapidly in cancer cell lines derived from lung, bladder and prostate tumors. Blocking autophagy with either pharmacological inhibitors or siRNAs targeting the key autophagy factors BECN1/Beclin 1 or ATG7 effectively increased TNFSF10-induced apoptotic cytotoxicity, substantiating a cytoprotective role for TNFSF10-induced autophagy. Blocking MAPK8 but not NFκB effectively blocked autophagy, suggesting that MAPK8 is the main pathway for TNFSF10-induced autophagy. In addition, blocking MAPK8 effectively inhibited degradation of BCL2L1/Bcl-xL and reduction of the autophagy-suppressing BCL2L1–BECN1complex. Knockdown of TRAF2 or RIPK1 effectively suppressed TNFSF10-induced MAPK8 activation and autophagy. Furthermore, suppressing autophagy inhibited expression of antiapoptosis factors BIRC2/cIAP1, BIRC3/cIAP2, XIAP and CFLAR/c-FLIP and increased the formation of TNFSF10-induced death-inducing signaling complex (DISC). These results reveal a critical role for the MAPK8 activation pathway through TRAF2 and RIPK1 for TNFSF10-induced autophagy that blunts apoptosis in cancer cells. Thus, suppression of MAPK8-mediated autophagy could be utilized for sensitizing cancer cells to therapy with TNFSF10. 相似文献
88.
A number of platinum(II) complexes with ammine or 1R,2R-diaminocyclohexane as carrier ligands and 1-(methoxy-substituted benzyl) azetidine-3,3-dicarboxylate as leaving groups were synthesized and spectrally characterized. Biological evaluation in vitro showed that some of compounds showed positive antitumor activity. In particular, complex 3a, (1R,2R-diaminocyclohexane)[1-(3-methoxylbenzyl) azetidine-3,3-dicarboxylato)-O,O'] platinum(II), possessed a potent antitumor effect comparable to cisplatin and/or oxaliplatin, and very low toxicity in vivo. Preliminary antitumor mechanism of 3a has been investigated by cell apoptosis assays compared with cisplatin and oxaliplatin. 相似文献
89.
为了实现硬脂酰-辅酶A脱氢酶1编码基因在乳酸乳球菌中的表达,采用PCR技术扩增获得人类scd1的编码序列。Nco I和Xba I双酶切后定向插入到食品级表达载体pNZ8149中,构建表达载体pNZ8149-scd1。电转化乳酸乳球菌NZ3900,经菌落PCR和测序鉴定scd1基因成功插入到乳酸乳球菌中。在乳链菌肽诱导下进行scd1的表达,转化株提取脂肪酸,进行脂肪酸含量的气相色谱分析。结果显示,SCD1转化菌株中的C16∶1n-7和C18∶1n-7脂肪酸组分比转化pNZ8149的对照组乳酸菌分别提高了92%~169%和53%~127%。文中以scd1基因为例,尝试并证明了脂肪酸脱氢酶类基因能够在食品级乳酸菌中有效表达,为后续研究奠定了基础。 相似文献
90.
Zhongqing Chen Weihong Ding Ke Xu Jun Tan Chuanyu Sun Yuancheng Gou Shijun Tong Guowei Xia Zujun Fang Qiang Ding 《PloS one》2012,7(10)