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Many organisms adjust their reproductive phenology in response to climate change, but phenological sensitivity to temperature may vary between species. For example, resident and migratory birds have vastly different annual cycles, which can cause differential temperature sensitivity at the breeding grounds, and may affect competitive dynamics. Currently, however, adjustment to climate change in resident and migratory birds have been studied separately or at relatively small geographical scales with varying time series durations and methodologies. Here, we studied differential effects of temperature on resident and migratory birds using the mean egg laying initiation dates from 10 European nest box schemes between 1991 and 2015 that had data on at least one resident tit species and at least one migratory flycatcher species. We found that both tits and flycatchers advanced laying in response to spring warming, but resident tit populations advanced more strongly in relation to temperature increases than migratory flycatchers. These different temperature responses have already led to a divergence in laying dates between tits and flycatchers of on average 0.94 days per decade over the current study period. Interestingly, this divergence was stronger at lower latitudes where the interval between tit and flycatcher phenology is smaller and winter conditions can be considered more favorable for resident birds. This could indicate that phenological adjustment to climate change by flycatchers is increasingly hampered by competition with resident species. Indeed, we found that tit laying date had an additional effect on flycatcher laying date after controlling for temperature, and this effect was strongest in areas with the shortest interval between both species groups. Combined, our results suggest that the differential effect of climate change on species groups with overlapping breeding ecology affects the phenological interval between them, potentially affecting interspecific interactions.  相似文献   
23.
The higher proportion of males of the invasive round goby Neogobius melanostomus in samples from two activity selective passive fishing gears compared with one activity non‐selective fishing gear in three Dutch lakes is related to higher male locomotory activity and is a sex‐dependent trait. This difference in activity reflects the different ecology of male and female N. melanostomus.  相似文献   
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Background

Thellungiella halophila (also known as Thellungiella salsuginea) is a model halophyte with a small plant size, short life cycle, and small genome. It easily undergoes genetic transformation by the floral dipping method used with its close relative, Arabidopsis thaliana. Thellungiella genes exhibit high sequence identity (approximately 90% at the cDNA level) with Arabidopsis genes. Furthermore, Thellungiella not only shows tolerance to extreme salinity stress, but also to chilling, freezing, and ozone stress, supporting the use of Thellungiella as a good genomic resource in studies of abiotic stress tolerance.

Results

We constructed a full-length enriched Thellungiella (Shan Dong ecotype) cDNA library from various tissues and whole plants subjected to environmental stresses, including high salinity, chilling, freezing, and abscisic acid treatment. We randomly selected about 20 000 clones and sequenced them from both ends to obtain a total of 35 171 sequences. CAP3 software was used to assemble the sequences and cluster them into 9569 nonredundant cDNA groups. We named these cDNAs "RTFL" (RIKEN Thellungiella Full-Length) cDNAs. Information on functional domains and Gene Ontology (GO) terms for the RTFL cDNAs were obtained using InterPro. The 8289 genes assigned to InterPro IDs were classified according to the GO terms using Plant GO Slim. Categorical comparison between the whole Arabidopsis genome and Thellungiella genes showing low identity to Arabidopsis genes revealed that the population of Thellungiella transport genes is approximately 1.5 times the size of the corresponding Arabidopsis genes. This suggests that these genes regulate a unique ion transportation system in Thellungiella.

Conclusion

As the number of Thellungiella halophila (Thellungiella salsuginea) expressed sequence tags (ESTs) was 9388 in July 2008, the number of ESTs has increased to approximately four times the original value as a result of this effort. Our sequences will thus contribute to correct future annotation of the Thellungiella genome sequence. The full-length enriched cDNA clones will enable the construction of overexpressing mutant plants by introduction of the cDNAs driven by a constitutive promoter, the complementation of Thellungiella mutants, and the determination of promoter regions in the Thellungiella genome.  相似文献   
26.
Temperate species are projected to experience the greatest temperature increases across a range of modelled climate change scenarios, and climate warming has been linked to geographical range and population changes of individual species at such latitudes. However, beyond the multiple modelling approaches, we lack empirical evidence of contemporary climate change impacts on populations in broad taxonomic groups and at continental scales. Identifying reliable predictors of species resilience or susceptibility to climate warming is of critical importance in assessing potential risks to species, ecosystems and ecosystem services. Here we analysed long‐term trends of 110 common breeding birds across Europe (20 countries), to identify climate niche characteristics, adjusted to other environmental and life history traits, that predict large‐scale population changes accounting for phylogenetic relatedness among species. Beyond the now well‐documented decline of farmland specialists, we found that species with the lowest thermal maxima (as the mean spring and summer temperature of the hottest part of the breeding distribution in Europe) showed the sharpest declines between 1980 and 2005. Thermal maximum predicted the recent trends independently of other potential predictors. This study emphasizes the need to account for both land‐use and climate changes to assess the fate of species. Moreover, we highlight that thermal maximum appears as a reliable and simple predictor of the long‐term trends of such endothermic species facing climate change.  相似文献   
27.
Two Orthotrichum species of the subgenus Orthophyllum were compared with other representatives of this genus using the internally transcribed spacer regions 1 and 2, the chloroplast trnH-psbA region and ISSR and ISJ DNA markers. The applied DNA markers revealed many bands and mutations specific only to O. gymnostomum and O. obtusifolium. A phylogenetic analysis clearly supported the previous concepts postulating that species of the subgenus Orthophyllum should be recognized as separate genus Nyholmiella.  相似文献   
28.
Species belonging to the Festuca-Lolium complex are important forage and turf species and as such, have been studied intensively. However, their out-crossing nature and limited availability of molecular markers make genetic studies difficult. Here, we report on saturation of F. pratensis and L. multiflorum genetic maps using Diversity Array Technology (DArT) markers and the DArTFest array.The 530 and 149 DArT markers were placed on genetic maps of L. multiflorum and F. pratensis, respectively, with overlap of 20 markers, which mapped in both species. The markers were sequenced and comparative sequence analysis was performed between L. multiflorum, rice and Brachypodium. The utility of the DArTFest array was then tested on a Festulolium population FuRs0357 in an integrated analysis using the DArT marker map positions to study associations between markers and freezing tolerance. Ninety six markers were significantly associated with freezing tolerance and five of these markers were genetically mapped to chromosomes 2, 4 and 7. Three genomic loci associated with freezing tolerance in the FuRs0357 population co-localized with chromosome segments and QTLs previously identified to be associated with freezing tolerance. The present work clearly confirms the potential of the DArTFest array in genetic studies of the Festuca-Lolium complex. The annotated DArTFest array resources could accelerate further studies and improvement of desired traits in Festuca-Lolium species.  相似文献   
29.
The nectarivory of sunbirds in the Old World and hummingbirds in the New World evolved independently. While both groups are specialised in their feeding apparatuses, hummingbirds are moreover famous for their adaptations to sustained hovering flight. Recently, an example of a pollination system of the invasive plant Nicotiana glauca has been used to show that less adapted sunbirds also are frequently able to hover. Nevertheless, the question has remained why plants adapted to bird hovering pollination do not occur outside the New World. In this paper we show that the long‐peduncle Cameroonian Impatiens sakeriana is not capable of autonomous selfing and can be pollinated only by two often hovering sunbirds, the Cameroon sunbird Cyanomitra oritis and the northern double‐collared sunbird Cinnyris reichenowi. Our study revealed that this plant is highly specialised for pollination by C. oritis. Cinnyris reichenowi hovers less frequently and often thieves nectar by piercing the flower spur when perching. This study shows that pollination systems occurring in the Old World follow similar evolutionary trends as systems including hovering hummingbirds in the New World.  相似文献   
30.
Antifungal drug ketoconazole causes severe drug-drug interactions by influencing gene expression and catalytic activity of major drug-metabolizing enzyme cytochrome P450 CYP3A4. Ketoconazole is administered in the form of racemic mixture of two cis-enantiomers, i.e. (+)-ketoconazole and (−)-ketoconazole. Many enantiopure drugs were introduced to human pharmacotherapy in last two decades. In the current paper, we have examined the effects of ketoconazole cis-enantiomers on the expression of CYP3A4 in human hepatocytes and HepG2 cells and on catalytic activity of CYP3A4 in human liver microsomes. We show that both ketoconazole enantiomers induce CYP3A4 mRNA and protein in human hepatocytes and HepG2 cells. Gene reporter assays revealed partial agonist activity of ketoconazole enantiomers towards pregnane X receptor PXR. Catalytic activity of CYP3A4/5 towards two prototypic substrates of CYP3A enzymes, testosterone and midazolam, was determined in presence of both (+)-ketoconazole and (−)-ketoconazole in human liver microsomes. Overall, both ketoconazole cis-enantiomers induced CYP3A4 in human cells and inhibited CYP3A4 in human liver microsomes. While interaction of ketoconazole with PXR and induction of CYP3A4 did not display enantiospecific pattern, inhibition of CYP3A4 catalytic activity by ketoconazole differed for ketoconazole cis-enantiomers ((+)-ketoconazole IC50 1.69 µM, Ki 0.92 µM for testosterone, IC50 1.46 µM, Ki 2.52 µM for midazolam; (−)-ketoconazole IC50 0.90 µM, Ki 0.17 µM for testosterone, IC50 1.04 µM, Ki 1.51 µM for midazolam).  相似文献   
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