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151.
In this study, the microsatellite technique was used to evaluate the genetic variability in populations of collared and white-lipped peccaries kept in captivity. Six primers developed for domestic pigs were used and amplified in both species. They revealed the presence of five polymorphic loci and one monomorphic locus. The polymorphic loci included 4 of the 16 alleles in collared peccaries, and 3 of the 10 alleles in the white-lipped peccaries. Polymorphic information content (PIC) in both species and all the loci was highly informative. The probability of paternity exclusion (PEC), if one of the parents is known, was almost as high in white-lipped peccaries (95.53%) as in the collared (99,48%). The Fst values for collared (0.042) and white-lipped (0.1387) peccaries showed that both populations are not structured. The Fis values for all loci, except ACTG2 in white-lipped peccaries (-0.0275) and in both species (0.1985 to 0.9284 in collared peccaries and 0.3621 to 0.4754 in the white-lipped), revealed a high level of homozygosis, probably caused by inbreeding. Data on heterologous amplification and genetic variability in collared and white-lipped peccaries are presented for the first time. 相似文献
152.
Sun H Lapidus A Nolan M Lucas S Del Rio TG Tice H Cheng JF Tapia R Han C Goodwin L Pitluck S Pagani I Ivanova N Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Djao OD Rohde M Sikorski J Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2010,3(3):325-336
Nocardiopsis dassonvillei (Brocq-Rousseau 1904) Meyer 1976 is the type species of the genus Nocardiopsis, which in turn is the type genus of the family Nocardiopsaceae. This species is of interest because of its ecological versatility. Members of N. dassonvillei have been isolated from a large variety of natural habitats such as soil and marine sediments, from different plant and animal materials as well as from human patients. Moreover, representatives of the genus Nocardiopsis participate actively in biopolymer degradation. This is the first complete genome sequence in the family Nocardiopsaceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 6,543,312 bp long genome consist of a 5.77 Mbp chromosome and a 0.78 Mbp plasmid and with its 5,570 protein-coding and 77 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
153.
Roxane Chiori Muriel Jager Elsa Denker Patrick Wincker Corinne Da Silva Hervé Le Guyader Micha?l Manuel Eric Quéinnec 《PloS one》2009,4(1)
Background
The early evolution and diversification of Hox-related genes in eumetazoans has been the subject of conflicting hypotheses concerning the evolutionary conservation of their role in axial patterning and the pre-bilaterian origin of the Hox and ParaHox clusters. The diversification of Hox/ParaHox genes clearly predates the origin of bilaterians. However, the existence of a “Hox code” predating the cnidarian-bilaterian ancestor and supporting the deep homology of axes is more controversial. This assumption was mainly based on the interpretation of Hox expression data from the sea anemone, but growing evidence from other cnidarian taxa puts into question this hypothesis.Methodology/Principal Findings
Hox, ParaHox and Hox-related genes have been investigated here by phylogenetic analysis and in situ hybridisation in Clytia hemisphaerica, an hydrozoan species with medusa and polyp stages alternating in the life cycle. Our phylogenetic analyses do not support an origin of ParaHox and Hox genes by duplication of an ancestral ProtoHox cluster, and reveal a diversification of the cnidarian HOX9-14 genes into three groups called A, B, C. Among the 7 examined genes, only those belonging to the HOX9-14 and the CDX groups exhibit a restricted expression along the oral-aboral axis during development and in the planula larva, while the others are expressed in very specialised areas at the medusa stage.Conclusions/Significance
Cross species comparison reveals a strong variability of gene expression along the oral-aboral axis and during the life cycle among cnidarian lineages. The most parsimonious interpretation is that the Hox code, collinearity and conservative role along the antero-posterior axis are bilaterian innovations. 相似文献154.
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156.
John A. Harrison Roxane J. Maranger Richard B. Alexander Anne E. Giblin Pierre-Andre Jacinthe Emilio Mayorga Sybil P. Seitzinger Daniel J. Sobota Wilfred M. Wollheim 《Biogeochemistry》2009,93(1-2):143-157
Human activities have greatly increased the transport of biologically available nitrogen (N) through watersheds to potentially sensitive coastal ecosystems. Lentic water bodies (lakes and reservoirs) have the potential to act as important sinks for this reactive N as it is transported across the landscape because they offer ideal conditions for N burial in sediments or permanent loss via denitrification. However, the patterns and controls on lentic N removal have not been explored in great detail at large regional to global scales. In this paper we describe, evaluate, and apply a new, spatially explicit, annual-scale, global model of lentic N removal called NiRReLa (Nitrogen Retention in Reservoirs and Lakes). The NiRReLa model incorporates small lakes and reservoirs than have been included in previous global analyses, and also allows for separate treatment and analysis of reservoirs and natural lakes. Model runs for the mid-1990s indicate that lentic systems are indeed important sinks for N and are conservatively estimated to remove 19.7 Tg N year?1 from watersheds globally. Small lakes (<50 km2) were critical in the analysis, retaining almost half (9.3 Tg N year?1) of the global total. In model runs, capacity of lakes and reservoirs to remove watershed N varied substantially at the half-degree scale (0–100%) both as a function of climate and the density of lentic systems. Although reservoirs occupy just 6% of the global lentic surface area, we estimate they retain ~33% of the total N removed by lentic systems, due to a combination of higher drainage ratios (catchment surface area:lake or reservoir surface area), higher apparent settling velocities for N, and greater average N loading rates in reservoirs than in lakes. Finally, a sensitivity analysis of NiRReLa suggests that, on-average, N removal within lentic systems will respond more strongly to changes in land use and N loading than to changes in climate at the global scale. 相似文献
157.
p62 and NDP52 proteins target intracytosolic Shigella and Listeria to different autophagy pathways 总被引:1,自引:0,他引:1
Mostowy S Sancho-Shimizu V Hamon MA Simeone R Brosch R Johansen T Cossart P 《The Journal of biological chemistry》2011,286(30):26987-26995
Autophagy is an important mechanism of innate immune defense. We have recently shown that autophagy components are recruited with septins, a new and increasingly characterized cytoskeleton component, to intracytosolic Shigella that have started to polymerize actin. On the other hand, intracytosolic Listeria avoids autophagy recognition by expressing ActA, a bacterial effector required for actin polymerization. Here, we exploit Shigella and Listeria as intracytosolic tools to characterize different pathways of selective autophagy. We show that the ubiquitin-binding adaptor proteins p62 and NDP52 target Shigella to an autophagy pathway dependent upon septin and actin. In contrast, p62 or NDP52 targets the Listeria ActA mutant to an autophagy pathway independent of septin or actin. TNF-α, a host cytokine produced upon bacterial infection, stimulates p62-mediated autophagic activity and restricts the survival of Shigella and the Listeria ActA mutant. These data provide a new molecular framework to understand the emerging complexity of autophagy and its ability to achieve specific clearance of intracytosolic bacteria. 相似文献
158.
Understanding the effects of disturbance and secondary succession on spatio-temporal patterns in the abundance of species
is stymied by a lack of long-term demographic data, especially in response to infrequent and high intensity disturbances,
such as hurricanes. Moreover, resistance and resilience to hurricane-induced disturbance may be mediated by legacies of previous
land use, although such interactive effects are poorly understood, especially in tropical environments. We address these central
issues in disturbance ecology by analyzing an extensive dataset, spanning the impacts of Hurricanes Hugo and Georges, on the
abundance of a Neotropical walking stick, Lamponius portoricensis, in tabonuco rainforest of Puerto Rico during the wet and dry seasons from 1991 to 2007. By synthesizing data from two proximate
sites in tabonuco forest, we show that resistance to Hurricane Hugo (97% reduction in abundance) was much less than resistance
to Hurricane Georges (21% reduction in abundance). Based on a powerful statistical approach (generalized linear mixed-effects
models with Poisson error terms), we documented that the temporal trajectories of abundance during secondary succession (i.e.,
patterns of resilience) differed between hurricanes and among historical land use categories, but that the effects of hurricanes
and land use histories were independent of each other. These complex results likely arise because of differences in the intensities
of the two hurricanes with respect to microclimatic effects (temperature and moisture) in the forest understory, as well as
to time-lags in the response of L. portoricensis to changes in the abundance and distribution of preferred food plants (Piper) in post-hurricane environments. 相似文献
159.
Land M Held B Gronow S Abt B Lucas S Del Rio TG Nolan M Tice H Cheng JF Pitluck S Liolios K Pagani I Ivanova N Mavromatis K Mikhailova N Pati A Tapia R Han C Goodwin L Chen A Palaniappan K Hauser L Brambilla EM Rohde M Göker M Detter JC Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lapidus A 《Standards in genomic sciences》2011,4(2):233-243
Bacteroides coprosuis Whitehead et al. 2005 belongs to the genus Bacteroides, which is a member of the family Bacteroidaceae. Members of the genus Bacteroides in general are known as beneficial protectors of animal guts against pathogenic microorganisms, and as contributors to the degradation of complex molecules such as polysaccharides. B. coprosuis itself was isolated from a manure storage pit of a swine facility, but has not yet been found in an animal host. The species is of interest solely because of its isolated phylogenetic location. The genome of B. coprosuis is already the 5(th) sequenced type strain genome from the genus Bacteroides. The 2,991,798 bp long genome with its 2,461 protein-coding and 78 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
160.
Pagani I Lapidus A Nolan M Lucas S Hammon N Deshpande S Cheng JF Chertkov O Davenport K Tapia R Han C Goodwin L Pitluck S Liolios K Mavromatis K Ivanova N Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Detter JC Brambilla E Kannan KP Djao OD Rohde M Pukall R Spring S Göker M Sikorski J Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2011,4(1):100-110
Desulfobulbus propionicus Widdel 1981 is the type species of the genus Desulfobulbus, which belongs to the family Desulfobulbaceae. The species is of interest because of its great implication in the sulfur cycle in aquatic sediments, its large substrate spectrum and a broad versatility in using various fermentation pathways. The species was the first example of a pure culture known to disproportionate elemental sulfur to sulfate and sulfide. This is the first completed genome sequence of a member of the genus Desulfobulbus and the third published genome sequence from a member of the family Desulfobulbaceae. The 3,851,869 bp long genome with its 3,351 protein-coding and 57 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献