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971.
Marathe C Bradley MN Hong C Chao L Wilpitz D Salazar J Tontonoz P 《Journal of lipid research》2009,50(2):214-224
Macrophage lipid metabolism and inflammatory responses are both regulated by the nuclear receptors PPAR and LXR. Emerging links between inflammation and metabolic disease progression suggest that PPAR and LXR signaling may alter macrophage function and thereby impact systemic metabolism. In this study, the function of macrophage PPAR and LXR in Th1-biased C57BL/6 mice was tested using a bone marrow transplantation approach with PPARgamma(-/-), PPARdelta(-/-), PPARgammadelta(-/-), and LXRalphabeta(-/-) cells. Despite their inhibitory effects on inflammatory gene expression, loss of PPARs or LXRs in macrophages did not exert major effects on obesity or glucose tolerance induced by a high-fat diet. Treatment with rosiglitazone effectively improved glucose tolerance in mice lacking macrophage PPARgamma, suggesting that cell types other than macrophages are the primary mediators of the anti-diabetic effects of PPARgamma agonists in our model system. C57BL/6 macrophages lacking PPARs or LXRs exhibited normal expression of most alternative activation gene markers, indicating that macrophage alternative activation is not absolutely dependent on these receptors in the C57BL/6 background under the conditions used here. These studies suggest that genetic background may be an important modifier of nuclear receptor effects in macrophages. Our results do not exclude a contribution of macrophage PPAR and LXR expression to systemic metabolism in certain contexts, but these factors do not appear to be dominant contributors to glucose tolerance in a high-fat-fed Th1-biased bone marrow transplant model. 相似文献
972.
Background
Clearance of synaptically released glutamate, and hence termination of glutamatergic neurotransmission, is carried out by glutamate transporters, most especially glutamate transporter-1 (GLT-1) and the glutamate-aspartate transporter (GLAST) that are located in astrocytes. It is becoming increasingly well appreciated that changes in the function and expression of GLT-1 and GLAST occur under different physiological and pathological conditions. Here we investigated the plasticity in expression of GLT-1 and GLAST in the spinal dorsal horn using immunohistochemistry following partial sciatic nerve ligation (PSNL) in rats.Results
Animals were confirmed to develop hypersensitivity to mechanical stimulation by 7 days following PSNL. Baseline expression of GLT-1 and GLAST in naive animals was only observed in astrocytes and not in either microglia or neurons. Microglia and astrocytes showed evidence of reactivity to the nerve injury when assessed at 7 and 14 days following PSNL evidenced by increased expression of OX-42 and GFAP, respectively. In contrast, the total level of GLT-1 and GLAST protein decreased at both 7 and 14 days after PSNL. Importantly, the cellular location of GLT-1 and GLAST was also altered in response to nerve injury. Whereas activated astrocytes showed a marked decrease in expression of GLT-1 and GLAST, activated microglia showed de novo expression of GLT-1 and GLAST at 7 days after PSNL and this was maintained through day 14. Neurons showed no expression of GLT-1 or GLAST at any time point.Conclusion
These results indicate that the expression of glutamate transporters in astrocytes and microglia are differentially regulated following nerve injury. 相似文献973.
Craig D. Blanchette Youn-Hi Woo Cynthia Thomas Nan Shen Todd A. Sulchek Amy L. Hiddessen 《PloS one》2009,4(6)
Background
Phagocytosis has been extensively examined in ‘professional’ phagocytic cells using pH sensitive dyes. However, in many of the previous studies, a separation between the end of internalization, beginning of acidification and completion of phagosomal-endosomal/lysosomal fusion was not clearly established. In addition, very little work has been done to systematically examine phagosomal maturation in ‘non-professional’ phagocytic cells. Therefore, in this study, we developed a simple method to measure and decouple particle internalization, phagosomal acidification and phagosomal-endosomal/lysosomal fusion in Madin-Darby Canine Kidney (MDCK) and Caco-2 epithelial cells.Methodology/Principal Findings
Our method was developed using a pathogen mimetic system consisting of polystyrene beads coated with Internalin A (InlA), a membrane surface protein from Listeria monocytogenes known to trigger receptor-mediated phagocytosis. We were able to independently measure the rates of internalization, phagosomal acidification and phagosomal-endosomal/lysosomal fusion in epithelial cells by combining the InlA-coated beads (InlA-beads) with antibody quenching, a pH sensitive dye and an endosomal/lysosomal dye. By performing these independent measurements under identical experimental conditions, we were able to decouple the three processes and establish time scales for each. In a separate set of experiments, we exploited the phagosomal acidification process to demonstrate an additional, real-time method for tracking bead binding, internalization and phagosomal acidification.Conclusions/Significance
Using this method, we found that the time scales for internalization, phagosomal acidification and phagosomal-endosomal/lysosomal fusion ranged from 23–32 min, 3–4 min and 74–120 min, respectively, for MDCK and Caco-2 epithelial cells. Both the static and real-time methods developed here are expected to be readily and broadly applicable, as they simply require fluorophore conjugation to a particle of interest, such as a pathogen or mimetic, in combination with common cell labeling dyes. As such, these methods hold promise for future measurements of receptor-mediated internalization in other cell systems, e.g. pathogen-host systems. 相似文献974.
Copeland A Spring S Göker M Schneider S Lapidus A Del Rio TG Tice H Cheng JF Chen F Nolan M Bruce D Goodwin L Pitluck S Ivanova N Mavrommatis K Ovchinnikova G Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CC Meincke L Sims D Brettin T Detter JC Han C Chain P Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lucas S 《Standards in genomic sciences》2009,1(1):29-37
Desulfomicrobium baculatum is the type species of the genus Desulfomicrobium, which is the type genus of the family Desulfomicrobiaceae. It is of phylogenetic interest because of the isolated location of the family Desulfomicrobiaceae within the order Desulfovibrionales. D. baculatum strain X(T) is a Gram-negative, motile, sulfate-reducing bacterium isolated from water-saturated manganese carbonate ore. It is strictly anaerobic and does not require NaCl for growth, although NaCl concentrations up to 6% (w/v) are tolerated. The metabolism is respiratory or fermentative. In the presence of sulfate, pyruvate and lactate are incompletely oxidized to acetate and CO(2). Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a member of the deltaproteobacterial family Desulfomicrobiaceae, and this 3,942,657 bp long single replicon genome with its 3494 protein-coding and 72 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
975.
Clum A Nolan M Lang E Glavina Del Rio T Tice H Copeland A Cheng JF Lucas S Chen F Bruce D Goodwin L Pitluck S Ivanova N Mavrommatis K Mikhailova N Pati A Chen A Palaniappan K Göker M Spring S Land M Hauser L Chang YJ Jeffries CC Chain P Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lapidus A 《Standards in genomic sciences》2009,1(1):38-45
Acidimicrobium ferrooxidans (Clark and Norris 1996) is the sole and type species of the genus, which until recently was the only genus within the actinobacterial family Acidimicrobiaceae and in the order Acidomicrobiales. Rapid oxidation of iron pyrite during autotrophic growth in the absence of an enhanced CO(2) concentration is characteristic for A. ferrooxidans. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the order Acidomicrobiales, and the 2,158,157 bp long single replicon genome with its 2038 protein coding and 54 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
976.
Land M Pukall R Abt B Göker M Rohde M Glavina Del Rio T Tice H Copeland A Cheng JF Lucas S Chen F Nolan M Bruce D Goodwin L Pitluck S Ivanova N Mavromatis K Ovchinnikova G Pati A Chen A Palaniappan K Hauser L Chang YJ Jefferies CC Saunders E Brettin T Detter JC Han C Chain P Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lapidus A 《Standards in genomic sciences》2009,1(1):21-28
Beutenbergia cavernae (Groth et al. 1999) is the type species of the genus and is of phylogenetic interest because of its isolated location in the actinobacterial suborder Micrococcineae. B. cavernae HKI 0122(T) is a Gram-positive, non-motile, non-spore-forming bacterium isolated from a cave in Guangxi (China). B. cavernae grows best under aerobic conditions and shows a rod-coccus growth cycle. Its cell wall peptidoglycan contains the diagnostic L-lysine ← L-glutamate interpeptide bridge. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first completed genome sequence from the poorly populated micrococcineal family Beutenbergiaceae, and this 4,669,183 bp long single replicon genome with its 4225 protein-coding and 53 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
977.
Ivanova N Gronow S Lapidus A Copeland A Glavina Del Rio T Nolan M Lucas S Chen F Tice H Cheng JF Saunders E Bruce D Goodwin L Brettin T Detter JC Han C Pitluck S Mikhailova N Pati A Mavrommatis K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Chain P Rohde C Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2009,1(2):126-132
Leptotrichia buccalis (Robin 1853) Trevisan 1879 is the type species of the genus, and is of phylogenetic interest because of its isolated location in the sparsely populated and neither taxonomically nor genomically adequately accessed family 'Leptotrichiaceae' within the phylum 'Fusobacteria'. Species of Leptotrichia are large, fusiform, non-motile, non-sporulating rods, which often populate the human oral flora. L. buccalis is anaerobic to aerotolerant, and saccharolytic. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first complete genome sequence of the order 'Fusobacteriales' and no more than the second sequence from the phylum 'Fusobacteria'. The 2,465,610 bp long single replicon genome with its 2306 protein-coding and 61 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
978.
Spring S Lapidus A Schröder M Gleim D Sims D Meincke L Glavina Del Rio T Tice H Copeland A Cheng JF Lucas S Chen F Nolan M Bruce D Goodwin L Pitluck S Ivanova N Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Chain P Saunders E Brettin T Detter JC Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Han C 《Standards in genomic sciences》2009,1(3):242-253
Desulfotomaculum acetoxidans Widdel and Pfennig 1977 was one of the first sulfate-reducing bacteria known to grow with acetate as sole energy and carbon source. It is able to oxidize substrates completely to carbon dioxide with sulfate as the electron acceptor, which is reduced to hydrogen sulfide. All available data about this species are based on strain 5575(T), isolated from piggery waste in Germany. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a Desulfotomaculum species with validly published name. The 4,545,624 bp long single replicon genome with its 4370 protein-coding and 100 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
979.
Nolan M Tindall BJ Pomrenke H Lapidus A Copeland A Glavina Del Rio T Lucas S Chen F Tice H Cheng JF Saunders E Han C Bruce D Goodwin L Chain P Pitluck S Ovchinikova G Pati A Ivanova N Mavromatis K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Brettin T Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Detter JC 《Standards in genomic sciences》2009,1(3):283-290
Rhodothermus marinus Alfredsson et al. 1995 is the type species of the genus and is of phylogenetic interest because the Rhodothermaceae represent the deepest lineage in the phylum Bacteroidetes. R. marinus R-10(T) is a Gram-negative, non-motile, non-spore-forming bacterium isolated from marine hot springs off the coast of Iceland. Strain R-10(T) is strictly aerobic and requires slightly halophilic conditions for growth. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the genus Rhodothermus, and only the second sequence from members of the family Rhodothermaceae. The 3,386,737 bp genome (including a 125 kb plasmid) with its 2914 protein-coding and 48 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
980.
Cheatgrass ( Bromus tectorum L.) is an exotic annual grass that has invaded approximately 40,000,000 ha of rangelands in the United States, including montane ecosystems that are important habitats for wildlife and livestock. In addition to well-understood mechanisms by which Cheatgrass gains competitive advantage, recent studies have shown that Cheatgrass may also change the associated soil microbial community to impact native perennial plants and promote the persistence of Cheatgrass. Furthermore, reducing plant-available N represents a tool for initiating conditions that accelerate successional change from annual- to perennial-dominated communities. At a montane, mixed shrub–grassland Cheatgrass-dominated site in Colorado, we applied sucrose to reduce available N, and we added soil from a native plant community in order to reestablish the microbial community. This approach tested the idea that intact native soil microbial communities may enhance the beneficial effect of reducing soil N availability in a restoration setting. By the end of the experiment, reduced N availability decreased Cheatgrass by 9.8%, non-native annual/biennial plant cover by 15.0%, and increased relative perennial plant cover by 13.4%; soil inoculation reduced Cheatgrass by 7.6% and increased perennial abundance by 11.3%. Soil inoculum additions and reduced N availability both contributed toward restoring a perennial-dominated community and demonstrates that addition of native soil inoculum may be a useful tool for restoration efforts. 相似文献