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131.
Eukaryotic molecular diversity within the picoplanktonic size-fraction has primarily been studied in marine surface waters. Here, the vertical distribution of picoeukaryotic diversity was investigated in the Sargasso Sea from euphotic to abyssal waters, using size-fractionated samples (< 2 microm). 18S rRNA gene clone libraries were used to generate sequences from euphotic zone samples (deep chlorophyll maximum to the surface); the permanent thermocline (500 m); and the pelagic deep-sea (3000 m). Euphotic zone and deep-sea data contrasted strongly, the former displaying greater diversity at the first-rank taxon level, based on 232 nearly full-length sequences. Deep-sea sequences belonged almost exclusively to the Alveolata and Radiolaria, while surface samples also contained known and putative photosynthetic groups, such as unique Chlorarachniophyta and Chrysophyceae sequences. Phylogenetic analyses placed most Alveolata and Stramenopile sequences within previously reported 'environmental' clades, i.e. clades within the Novel Alveolate groups I and II (NAI and NAII), or the novel Marine Stramenopiles (MAST). However, some deep-sea NAII formed distinct, bootstrap supported clades. Stramenopiles were recovered from the euphotic zone only, although many MAST are reportedly heterotrophic, making the observed distribution a point for further investigation. An unexpectedly high proportion of radiolarian sequences were recovered. From these, five environmental radiolarian clades, RAD-I to RAD-V, were identified. RAD-IV and RAD-V were composed of Taxopodida-like sequences, with the former solely containing Sargasso Sea sequences, although from all depth zones sampled. Our findings highlight the vast diversity of these protists, most of which remain uncultured and of unknown ecological function. 相似文献
132.
A new look towards BAC-based array CGH through a comprehensive comparison with oligo-based array CGH
Nicolas Wicker Annaïck Carles Ian G Mills Maija Wolf Abhi Veerakumarasivam Henrik Edgren Fabrice Boileau Bohdan Wasylyk Jack A Schalken David E Neal Olli Kallioniemi Olivier Poch 《BMC genomics》2007,8(1):1-10
Background
Natural populations of the teleost fish Fundulus heteroclitus tolerate a broad range of environmental conditions including temperature, salinity, hypoxia and chemical pollutants. Strikingly, populations of Fundulus inhabit and have adapted to highly polluted Superfund sites that are contaminated with persistent toxic chemicals. These natural populations provide a foundation to discover critical gene pathways that have evolved in a complex natural environment in response to environmental stressors.Results
We used Fundulus cDNA arrays to compare metabolic gene expression patterns in the brains of individuals among nine populations: three independent, polluted Superfund populations and two genetically similar, reference populations for each Superfund population. We found that up to 17% of metabolic genes have evolved adaptive changes in gene expression in these Superfund populations. Among these genes, two (1.2%) show a conserved response among three polluted populations, suggesting common, independently evolved mechanisms for adaptation to environmental pollution in these natural populations.Conclusion
Significant differences among individuals between polluted and reference populations, statistical analyses indicating shared adaptive changes among the Superfund populations, and lack of reduction in gene expression variation suggest that common mechanisms of adaptive resistance to anthropogenic pollutants have evolved independently in multiple Fundulus populations. Among three independent, Superfund populations, two genes have a common response indicating that high selective pressures may favor specific responses. 相似文献133.
Adrien?NivoliezEmail author Philippe?Veisseire Elina?Alaterre Caroline?Dausset Fabrice?Baptiste Olivier?Camarès Marylise?Paquet-Gachinat Muriel?Bonnet Christiane?Forestier Stéphanie?Bornes 《Applied microbiology and biotechnology》2015,99(1):399-411
The influence of the industrial process on the properties of probiotics, administered as complex manufactured products, has been poorly investigated. In the present study, we comparatively assessed the cell wall characteristics of the probiotic strain Lactobacillus rhamnosus Lcr35® together with three of its commercial formulations with intestinal applications. Putative secreted and transmembrane-protein-encoding genes were initially searched in silico in the genome of L. rhamnosus Lcr35®. A total of 369 candidate genes were identified which expressions were followed using a custom Lactobacillus DNA chip. Among them, 60 or 67 genes had their expression either upregulated or downregulated in the Lcr Restituo® packet or capsule formulations, compared to the native Lcr35® strain. Moreover, our data showed that the probiotic formulations (Lcr Lenio®, Lcr restituo® capsule and packet) showed a better capacity to adhere to intestinal epithelial Caco-2 cells than the native Lcr35® strain. Microbial (MATS) tests showed that the probiotic was an electron donor and that they were more hydrophilic than the native strain. The enhanced adhesion capacity of the active pharmaceutical ingredients (APIs) to epithelial Caco-2 cells and their antipathogen effect could be due to this greater surface hydrophilic character. These findings suggest that the manufacturing process influences the protein composition and the chemical properties of the cell wall. It is therefore likely that the antipathogen effect of the formulation is modulated by the industrial process. Screening of the manufactured products’ properties would therefore represent an essential step in evaluating the effects of probiotic strains. 相似文献
134.
Fanny Jaudon Fabrice Raynaud Rosine Wehrlé Jean-Michel Bellanger Mohamed Doulazmi Guilan Vodjdani Stéphane Gasman Laurent Fagni Isabelle Dusart Anne Debant Susanne Schmidt 《Molecular biology of the cell》2015,26(11):2112-2127
By regulating actin cytoskeleton dynamics, Rho GTPases and their activators RhoGEFs are implicated in various aspects of neuronal differentiation, including dendritogenesis and synaptogenesis. Purkinje cells (PCs) of the cerebellum, by developing spectacular dendrites covered with spines, represent an attractive model system in which to decipher the molecular signaling underlying these processes. To identify novel regulators of dendritic spine morphogenesis among members of the poorly characterized DOCK family of RhoGEFs, we performed gene expression profiling of fluorescence-activated cell sorting (FACS)-purified murine PCs at various stages of their postnatal differentiation. We found a strong increase in the expression of the Cdc42-specific GEF DOCK10. Depleting DOCK10 in organotypic cerebellar cultures resulted in dramatic dendritic spine defects in PCs. Accordingly, in mouse hippocampal neurons, depletion of DOCK10 or expression of a DOCK10 GEF-dead mutant led to a strong decrease in spine density and size. Conversely, overexpression of DOCK10 led to increased spine formation. We show that DOCK10 function in spinogenesis is mediated mainly by Cdc42 and its downstream effectors N-WASP and PAK3, although DOCK10 is also able to activate Rac1. Our global approach thus identifies an unprecedented function for DOCK10 as a novel regulator of dendritic spine morphogenesis via a Cdc42-mediated pathway. 相似文献
135.
Guillaume Marcion Renaud Seigneuric Evelyne Chavanne Yves Artur Lo?c Briand Tarik Hadi Jessica Gobbo Carmen Garrido Fabrice Neiers 《Cell stress & chaperones》2015,20(1):61-72
The human inducible heat shock protein 70 (hHsp70), which is involved in several major pathologies, including neurodegenerative disorders and cancer, is a key molecular chaperone and contributes to the proper protein folding and maintenance of a large number of protein structures. Despite its role in disease, the current structural knowledge of hHsp70 is almost exclusively based on its Escherichia coli homolog, DnaK, even though these two proteins only share ~50 % amino acid identity. For the first time, we describe a complete heterologous production and purification strategy that allowed us to obtain a large amount of soluble, full-length, and non-tagged hHsp70. The protein displayed both an ATPase and a refolding activity when combined to the human Hsp40. Multi-angle light scattering and bio-layer interferometry analyses demonstrated the ability of hHsp70 to homodimerize. The role of the C-terminal part of hHsp70 was identified and confirmed by a study of a truncated version of hHsp70 that could neither dimerize nor present refolding activity.
Electronic supplementary material
The online version of this article (doi:10.1007/s12192-014-0526-3) contains supplementary material, which is available to authorized users. 相似文献136.
137.
ATGL and HSL are not coordinately regulated in response to fuel partitioning in fasted rats 总被引:2,自引:0,他引:2
Prolonged fasting is characterized by lipid mobilization (Phase 2), followed by protein breakdown (Phase 3). Knowing that body lipids are not exhausted in Phase 3, we investigated whether changes in the metabolic status of prolonged fasted rats are associated with differences in the expression of epididymal adipose tissue proteins involved in lipid mobilization. The final body mass, body lipid content, locomotor activity and metabolite and hormone plasma levels differed between groups. Compared with fed rats, adiposity and epididymal fat mass decreased in Phase 2 (approximately two- to threefold) and Phase 3 (∼4.5-14-fold). Plasma nonesterified fatty acids (NEFA) concentrations were increased in Phase 2 (approximately twofold) and decreased in Phase 3 (approximately twofold). Daily locomotor activity was markedly increased in Phase 3 (∼11-fold). Compared with the fed state, expressions of adipose triglyceride lipase (ATGL; mRNA and protein), hormone-sensitive lipase (HSL; mRNA) and phosphorylated HSL at residue Ser660 (HSL Ser660) were increased during Phase 2 (∼1.5-2-fold). HSL (mRNA and protein) and HSL Ser660 levels were lowered during Phase 3 (∼3-12-fold). Unlike HSL and HSL Ser660, ATGL expression did not correlate with circulating NEFA, mostly due to data from animals in Phase 3. At this stage, ATGL could play an essential role for maintaining a low mobilization rate of NEFA, possibly to sustain muscle performance and hence increased locomotor activity. We conclude that ATGL and HSL are not coordinately regulated in response to changes in fuel partitioning during prolonged food deprivation, ATGL appearing as the major lipase in late fasting. 相似文献
138.
139.
Pierre F Stefan E Nédellec AS Chevrel MC Regan CF Siddiqui-Jain A Macalino D Streiner N Drygin D Haddach M O'Brien SE Anderes K Ryckman DM 《Bioorganic & medicinal chemistry letters》2011,21(22):6687-6692
A novel class of pan-Pim kinase inhibitors was designed by modifying the CK2 inhibitor CX-4945. Introduction of a triazole or secondary amide functionality on the C-7 position and 2'-halogenoanilines on C-5 resulted in potent inhibitors of the Pim-1 and Pim-2 isoforms, with many analogs active at single digit nanomolar concentrations. The molecules inhibited the phosphorylation at Serine 112 of the apoptosis effector BAD, and had potent antiproliferative effects on the AML cell line MV-4-11 (IC(50) <30 nM). This work delivers an excellent lead-optimization platform for Pim targeting anticancer therapies. 相似文献
140.
Karsenti E Acinas SG Bork P Bowler C De Vargas C Raes J Sullivan M Arendt D Benzoni F Claverie JM Follows M Gorsky G Hingamp P Iudicone D Jaillon O Kandels-Lewis S Krzic U Not F Ogata H Pesant S Reynaud EG Sardet C Sieracki ME Speich S Velayoudon D Weissenbach J Wincker P;Tara Oceans Consortium 《PLoS biology》2011,9(10):e1001177
The structure, robustness, and dynamics of ocean plankton ecosystems remain poorly understood due to sampling, analysis, and computational limitations. The Tara Oceans consortium organizes expeditions to help fill this gap at the global level. 相似文献