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61.
Wolf population genetics in Europe: a systematic review,meta‐analysis and suggestions for conservation and management 下载免费PDF全文
Maris Hindrikson Jaanus Remm Malgorzata Pilot Raquel Godinho Astrid Vik Stronen Laima Baltrūnaité Sylwia D. Czarnomska Jennifer A. Leonard Ettore Randi Carsten Nowak Mikael Åkesson José Vicente López‐Bao Francisco Álvares Luis Llaneza Jorge Echegaray Carles Vilà Janis Ozolins Dainis Rungis Jouni Aspi Ladislav Paule Tomaž Skrbinšek Urmas Saarma 《Biological reviews of the Cambridge Philosophical Society》2017,92(3):1601-1629
The grey wolf (Canis lupus) is an iconic large carnivore that has increasingly been recognized as an apex predator with intrinsic value and a keystone species. However, wolves have also long represented a primary source of human–carnivore conflict, which has led to long‐term persecution of wolves, resulting in a significant decrease in their numbers, genetic diversity and gene flow between populations. For more effective protection and management of wolf populations in Europe, robust scientific evidence is crucial. This review serves as an analytical summary of the main findings from wolf population genetic studies in Europe, covering major studies from the ‘pre‐genomic era’ and the first insights of the ‘genomics era’. We analyse, summarize and discuss findings derived from analyses of three compartments of the mammalian genome with different inheritance modes: maternal (mitochondrial DNA), paternal (Y chromosome) and biparental [autosomal microsatellites and single nucleotide polymorphisms (SNPs)]. To describe large‐scale trends and patterns of genetic variation in European wolf populations, we conducted a meta‐analysis based on the results of previous microsatellite studies and also included new data, covering all 19 European countries for which wolf genetic information is available: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Germany, Belarus, Russia, Italy, Croatia, Bulgaria, Bosnia and Herzegovina, Greece, Spain and Portugal. We compared different indices of genetic diversity in wolf populations and found a significant spatial trend in heterozygosity across Europe from south‐west (lowest genetic diversity) to north‐east (highest). The range of spatial autocorrelation calculated on the basis of three characteristics of genetic diversity was 650?850 km, suggesting that the genetic diversity of a given wolf population can be influenced by populations up to 850 km away. As an important outcome of this synthesis, we discuss the most pressing issues threatening wolf populations in Europe, highlight important gaps in current knowledge, suggest solutions to overcome these limitations, and provide recommendations for science‐based wolf conservation and management at regional and Europe‐wide scales. 相似文献
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Sancho R Minguillón C 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,875(1):93-101
A proline oligopeptide-derived chiral selector (CS), containing 3,5-dimethylphenylcarbamate residues on the 4 position of the pyrrolidine rings, was bonded to a silica gel chromatographic matrix by the N-terminal group. The chromatographic behaviour of the resulting chiral stationary phase (CSP) was compared with that of a CSP containing the analogous monomeric CS and that resulting from bonding of the polyproline-derived CS by the carboxy-terminal group using several solvents as mobile phase. The CSs were also studied from the conformational point of view in solution using circular dichroism and 13C NMR. A relationship was found between the presence of an ordered conformation in the particular conditions used and increased enantioselectivity. 相似文献
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Antonio Díaz-Cruz Raquel Guinzberg Ruy Guerra Magdalena Vilchis Daniel Carrasco Francisco J. García-vázquez 《Free radical research》2013,47(6):663-672
It is known that adrenaline promotes hydroxyl radical generation in isolated rat hepatocytes. The aim of this work was to investigate a potential role of NADPH oxidase (Nox) isoforms for an oxidative stress signal in response to adrenaline in hepatocytes. Enriched plasma membranes from isolated rat liver cells were prepared for this purpose. These membranes showed catalytic activity of Nox isoforms, probably Nox 2 based on its complete inhibition with specific antibodies. NADPH was oxidized to convert O2 into superoxide radical, later transformed into H2O2. This enzymatic activity requires previous activation with either 3 mM Mn2+ or guanosine 5′-0-(3-thiotriphosphate) (GTPγS) plus adrenaline. Experimental conditions for activation and catalytic steps were set up: ATP was not required; S0.5 for NADPH was 44 μM; S0.5 for FAD was 8 μM; NADH up to 1 mM was not substrate, and diphenyleneiodonium was inhibitory. Activation with GTPγS plus adrenaline was dose- and Ca2+-dependent and proceeded through α1-adrenergic receptors (AR), whereas β-AR stimulation resulted in inhibition of Nox activity. These results lead us to propose H2O2 as additional transduction signal for adrenaline response in hepatic cells. 相似文献
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Lionete Nunes de Lima Caio C. Aragon Cesar Mateo Jose M. Palomo Raquel L.C. Giordano Paulo W. Tardioli Jose M. Guisan Gloria Fernandez-Lorente 《Process Biochemistry》2013,48(1):118-123
The soluble lipase from Pseudomonas fluorescens (PFL) forms bimolecular aggregates in which the hydrophobic active centers of the enzyme monomers are in close contact. This bimolecular aggregate could be immobilized by multipoint covalent linkages on glyoxyl supports at pH 8.5. The monomer of PFL obtained by incubation of the soluble enzyme in the presence of detergent (0.5% TRITON X-100) could not be immobilized under these conditions. The bimolecular aggregate has two amino terminal residues in the same plane. A further incubation of the immobilized derivative under more alkaline conditions (e.g., pH 10.5) allows a further multipoint attachment of lysine (Lys) residues located in the same plane as the amino terminal residues. Monomeric PFL was immobilized at pH 10.5 in the presence of 0.5% TRITON X-100. The properties of both PFL derivatives were compared. In general, the bimolecular derivatives were more active, more selective and more stable both in water and in organic solvents than the monomolecular ones. The bimolecular derivative showed twice the activity and a much higher selectivity (100 versus 20) for the hydrolysis of R,S-2-hydroxy-4-phenylbutyric acid ethyl ester (HPBEt) in aqueous media at pH 5.0 compared to the monomeric derivative. In experiments measuring thermal inactivation at 75 °C, the bimolecular derivative was 5-fold more stable than the monomeric derivative (and 50-fold more stable than a one-point covalently immobilized PFL derivative), and it had a half-life greater than 4 h. In organic solvents (cyclohexane and tert-amyl alcohol), the bimolecular derivative was much more stable and more active than the monomeric derivative in catalyzing the transesterification of olive oil with benzyl alcohol. 相似文献
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Raquel Monge-Ortiz Silvia Martínez-Llorens Lorenzo Márquez Francisco Javier Moyano Miguel Jover-Cerdá Ana Tomás-Vidal 《Archives of animal nutrition》2016,70(2):155-172
The effect of partial or total dietary substitution of fishmeal (FM) by vegetal protein sources on growth and feed efficiency was carried out in on-growing gilthead sea bream (mean initial weight 131 g). The Control diet (FM 100) contained FM as the primary protein source, while in Diets FM 25 and FM 0 the FM protein was replaced at 75% and 100%, respectively, by a vegetable protein mixture consisting of wheat gluten, soybean meal, rapeseed meal and crystalline amino acids. Diets FM 25 and FM 0 also contained krill meal at 47 g/kg in order to improve palatability. At the end of the trial (after 158 d), fish survival was above 90%. Final weight and the specific growth rate were statistically lower in fish fed the Control diet (361 g and 0.64%/d), compared with 390–396 g and 0.69–0.70%/d after feeding vegetal diets. No significant differences were found regarding feed intake and feed conversion ratio. The digestibility of protein and amino acids (determined with chromium oxide as indicator) was similar in all diets. The blood parameters were not significantly affected by treatments. The activity of trypsin and pepsin was significantly reduced after feeding Diet FM 0. In the distal intestine, the villi length in fish fed Diet FM 25 was significantly longer and the intestine of the fish fed the FM 100 diet showed a smaller number of goblet cells. In conclusion, a total FM substitution by a vegetal mix supplemented with synthetic amino acids in on-growing sea bream is feasible. 相似文献
69.
Limb outgrowth is maintained by a specialized group of cells, the apical ectodermal ridge (AER), a thickening of the limb epithelium at its distal tip. It has been shown that fibroblast growth factor (FGF) activity and activation of the Erk pathway are crucial for AER function. Recently, FLRT3, a transmembrane protein able to interact with FGF receptors, has been implicated in the activation of ERK by FGFs. In this study, we show that flrt3 expression is restricted to the AER, co-localizing its expression with fgf8 and pERK activity. Loss-of-function studies have shown that silencing of flrt3 affects the integrity of the AER and, subsequently, its proper function during limb bud outgrowth. Our data also indicate that flrt3 expression is not regulated by FGF activity in the AER, whereas ectopic WNT3A is able to induce flrt3 expression. Overall, our findings show that flrt3 is a key player during chicken limb development, being necessary but not sufficient for proper AER formation and maintenance under the control of BMP and WNT signalling. 相似文献
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