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991.
Kittinger JN Pandolfi JM Blodgett JH Hunt TL Jiang H Maly K McClenachan LE Schultz JK Wilcox BA 《PloS one》2011,6(10):e25460
Coral reef ecosystems are declining worldwide, yet regional differences in the trajectories, timing and extent of degradation highlight the need for in-depth regional case studies to understand the factors that contribute to either ecosystem sustainability or decline. We reconstructed social-ecological interactions in Hawaiian coral reef environments over 700 years using detailed datasets on ecological conditions, proximate anthropogenic stressor regimes and social change. Here we report previously undetected recovery periods in Hawaiian coral reefs, including a historical recovery in the MHI (~AD 1400-1820) and an ongoing recovery in the NWHI (~AD 1950-2009+). These recovery periods appear to be attributed to a complex set of changes in underlying social systems, which served to release reefs from direct anthropogenic stressor regimes. Recovery at the ecosystem level is associated with reductions in stressors over long time periods (decades+) and large spatial scales (>10(3) km(2)). Our results challenge conventional assumptions and reported findings that human impacts to ecosystems are cumulative and lead only to long-term trajectories of environmental decline. In contrast, recovery periods reveal that human societies have interacted sustainably with coral reef environments over long time periods, and that degraded ecosystems may still retain the adaptive capacity and resilience to recover from human impacts. 相似文献
992.
Increasing evidence has pointed to activated type I interferon signaling in tumors. However, the molecular basis for such activation and its role in tumorigenesis remain unclear. In the current studies, we report that activation of type I interferon (IFN) signaling in tumor cells is primarily due to elevated secretion of the type I interferon, IFN-β. Studies in oncogene-transformed cells suggest that oncogenes such as Ras and Src can activate IFN-β signaling. Significantly, elevated IFN-β signaling in Ras-transformed mammary epithelial MCF-10A cells was shown to contribute to Ras transformation as evidenced by morphological changes, anchorage-independent growth, and migratory properties. Our results demonstrate for the first time that the type I IFN, IFN-β, contributes to Ras transformation and support the notion that oncogene-induced cytokines play important roles in oncogene transformation. 相似文献
993.
Background
Peroxisome Proliferator Activated Receptor gamma (PPARγ) agonists, such as the thiazolinediones (TZDs), have been studied for their potential use as cancer therapeutic agents. We investigated the effect of four TZDs—Rosiglitazone (Rosi), Ciglitazone (CGZ), Troglitazone (TGZ), and Pioglitazone (Pio)—on ovarian cancer cell proliferation, PPARγ expression and PPAR luciferase reporter activity. We explored whether TZDs act in a PPARγ dependent or independent manner by utilizing molecular approaches to inhibit or overexpress PPARγ activity.Principal Findings
Treatment with CGZ or TGZ for 24 hours decreased proliferation in three ovarian cancer cell lines, Ovcar3, CaOv3, and Skov3, whereas Rosi and Pio had no effect. This decrease in Ovcar3 cell proliferation was due to a higher fraction of cells in the G0/G1 stage of the cell cycle. CGZ and TGZ treatment increased apoptosis after 4 hours of treatment but not after 8 or 12 hours. Treatment with TGZ or CGZ increased PPARγ mRNA expression in Ovcar3 cells; however, protein levels were unchanged. Surprisingly, luciferase promoter assays revealed that none of the TZDs increased PPARγ activity. Overexpression of wild type PPARγ increased reporter activity. This was further augmented by TGZ, Rosi, and Pio indicating that these cells have the endogenous capacity to mediate PPARγ transactivation. To determine whether PPARγ mediates the TZD-induced decrease in proliferation, cells were treated with CGZ or TGZ in the absence or presence of a dominant negative (DN) or wild type overexpression PPARγ construct. Neither vector changed the TZD-mediated cell proliferation suggesting this effect of TZDs on ovarian cancer cells may be PPARγ independent.Conclusions
CGZ and TGZ cause a decrease in ovarian cancer cell proliferation that is PPARγ independent. This concept is supported by the finding that a DN or overexpression of the wild type PPARγ did not affect the changes in cell proliferation and cell cycle. 相似文献994.
Pagani I Chertkov O Lapidus A Lucas S Del Rio TG Tice H Copeland A Cheng JF Nolan M Saunders E Pitluck S Held B Goodwin L Liolios K Ovchinikova G Ivanova N Mavromatis K Pati A Chen A Palaniappan K Land M Hauser L Jeffries CD Detter JC Han C Tapia R Ngatchou-Djao OD Rohde M Göker M Spring S Sikorski J Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(2):154-162
Marivirga tractuosa (Lewin 1969) Nedashkovskaya et al. 2010 is the type species of the genus Marivirga, which belongs to the family Flammeovirgaceae. Members of this genus are of interest because of their gliding motility. The species is of interest because representative strains show resistance to several antibiotics, including gentamicin, kanamycin, neomycin, polymixin and streptomycin. This is the first complete genome sequence of a member of the family Flammeovirgaceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 4,511,574 bp long chromosome and the 4,916 bp plasmid with their 3,808 protein-coding and 49 RNA genes are a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
995.
Wirth R Chertkov O Held B Lapidus A Nolan M Lucas S Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Ioanna P Ivanova N Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Bilek Y Hader T Rohde M Spring S Sikorski J Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2011,4(2):173-182
Desulfurococcus mucosus Zillig and Stetter 1983 is the type species of the genus Desulfurococcus, which belongs to the crenarchaeal family Desulfurococcaceae. The species is of interest because of its position in the tree of life, its ability for sulfur respiration, and several biotechnologically relevant thermostable and thermoactive extracellular enzymes. This is the third completed genome sequence of a member of the genus Desulfurococcus and already the 8(th) sequence from a member the family Desulfurococcaceae. The 1,314,639 bp long genome with its 1,371 protein-coding and 50 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
996.
Anderson I Sikorski J Zeytun A Nolan M Lapidus A Lucas S Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Huntemann M Mavromatis K Ovchinikova G Pati A Chen A Palaniappan K Land M Hauser L Brambilla EM Ngatchou-Djao OD Rohde M Tindall BJ Göker M Detter JC Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(3):322-330
Nitratifractor salsuginis Nakagawa et al. 2005 is the type species of the genus Nitratifractor, a member of the family Nautiliaceae. The species is of interest because of its high capacity for nitrate reduction via conversion to N(2) through respiration, which is a key compound in plant nutrition. The strain is also of interest because it represents the first mesophilic and facultatively anaerobic member of the Epsilonproteobacteria reported to grow on molecular hydrogen. This is the first completed genome sequence of a member of the genus Nitratifractor and the second sequence from the family Nautiliaceae. The 2,101,285 bp long genome with its 2,121 protein-coding and 54 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
997.
Anderson I Wirth R Lucas S Copeland A Lapidus A Cheng JF Goodwin L Pitluck S Davenport K Detter JC Han C Tapia R Land M Hauser L Pati A Mikhailova N Woyke T Klenk HP Kyrpides N Ivanova N 《Standards in genomic sciences》2011,5(1):12-20
Staphylothermus hellenicus belongs to the order Desulfurococcales within the archaeal phylum Crenarchaeota. Strain P8(T) is the type strain of the species and was isolated from a shallow hydrothermal vent system at Palaeochori Bay, Milos, Greece. It is a hyperthermophilic, anaerobic heterotroph. Here we describe the features of this organism together with the complete genome sequence and annotation. The 1,580,347 bp genome with its 1,668 protein-coding and 48 RNA genes was sequenced as part of a DOE Joint Genome Institute (JGI) Laboratory Sequencing Program (LSP) project. 相似文献
998.
Pukall R Zeytun A Lucas S Lapidus A Hammon N Deshpande S Nolan M Cheng JF Pitluck S Liolios K Pagani I Mikhailova N Ivanova N Mavromatis K Pati A Tapia R Han C Goodwin L Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Brambilla EM Rohde M Göker M Detter JC Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2011,4(2):163-172
Deinococcus maricopensis (Rainey and da Costa 2005) is a member of the genus Deinococcus, which is comprised of 44 validly named species and is located within the deeply branching bacterial phylum Deinococcus-Thermus. Strain LB-34(T) was isolated from a soil sample from the Sonoran Desert in Arizona. Various species of the genus Deinococcus are characterized by extreme radiation resistance, with D. maricopensis being resistant in excess of 10 kGy. Even though the genomes of three Deinococcus species, D. radiodurans, D. geothermalis and D. deserti, have already been published, no special physiological characteristic is currently known that is unique to this group. It is therefore of special interest to analyze the genomes of additional species of the genus Deinococcus to better understand how these species adapted to gamma- or UV ionizing-radiation. The 3,498,530 bp long genome of D. maricopensis with its 3,301 protein-coding and 66 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
999.
Daligault H Lapidus A Zeytun A Nolan M Lucas S Del Rio TG Tice H Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Huntemann M Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Brambilla EM Rohde M Verbarg S Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Woyke T 《Standards in genomic sciences》2011,4(3):352-360
Haliscomenobacter hydrossis van Veen et al. 1973 is the type species of the genus Haliscomenobacter, which belongs to order "Sphingobacteriales". The species is of interest because of its isolated phylogenetic location in the tree of life, especially the so far genomically uncharted part of it, and because the organism grows in a thin, hardly visible hyaline sheath. Members of the species were isolated from fresh water of lakes and from ditch water. The genome of H. hydrossis is the first completed genome sequence reported from a member of the family "Saprospiraceae". The 8,771,651 bp long genome with its three plasmids of 92 kbp, 144 kbp and 164 kbp length contains 6,848 protein-coding and 60 RNA genes, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
1000.
Woyke T Chertkov O Lapidus A Nolan M Lucas S Del Rio TG Tice H Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Huntemann M Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Brambilla EM Rohde M Mwirichia R Sikorski J Tindall BJ Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,5(1):21-29
Fluviicola taffensis O'Sullivan et al. 2005 belongs to the monotypic genus Fluviicola within the family Cryomorphaceae. The species is of interest because of its isolated phylogenetic location in the genome-sequenced fraction of the tree of life. Strain RW262(T) forms a monophyletic lineage with uncultivated bacteria represented in freshwater 16S rRNA gene libraries. A similar phylogenetic differentiation occurs between freshwater and marine bacteria in the family Flavobacteriaceae, a sister family to Cryomorphaceae. Most remarkable is the inability of this freshwater bacterium to grow in the presence of Na(+) ions. All other genera in the family Cryomorphaceae are from marine habitats and have an absolute requirement for Na(+) ions or natural sea water. F. taffensis is the first member of the family Cryomorphaceae with a completely sequenced and publicly available genome. The 4,633,577 bp long genome with its 4,082 protein-coding and 49 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献