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1.
Vascular smooth muscle cells (VSMCs) are exposed to mechanical cyclic stretch in vivo, which play important roles in maintenance of vascular homeostasis and regulation of pathological vascular remodeling. Reversible protein phosphorylation is crucial for intracellular signaling transduction. However, the dynamic phosphorylated profile induced by cyclic stretch in VSMCs is still unclear. Using the stable isotope labeling by amino acid in cell culture, VSMCs were labeled and exposed to 10% physiological cyclic stretch in vitro at 1.25 Hz for 0 min, 15 min, 30 min, 1 h and 6 h, respectively. Using TiO2 beads and liquid chromatography tandem mass spectrometry, the temporal phosphoproteomic profiles in response to cyclic stretch were then detected. Bioinformatics analysis including fuzzy c-means clustering, functional classifications, and Ingenuity Pathway Analysis were applied to further reveal the potential mechanotranduction networks. The results indicated that protein kinase C (PKCs) family, Rho-associated coiled-coil containing protein kinase 1 (ROCK1) and Akt may participate in cyclic-stretch induced VSMC functions. Cyclic stretch repressed the expression of ROCK1, while it had no significant effect on the phosphorylation of PKCα/βII, PKCζ/λ and PKCδ/θ. PKCθ was activated first at short time-phase (15 min and 30 min), and again at long time-phase (6 h, 12 h and 24 h). The activation of p-PKCμ was immediate and short-term, similar to p-Akt. Our present in vitro work hence revealed that cyclic stretch activates complex mechanotransduction networks, suggesting that novel mechanoresponsive molecules, i.e., PKCθ, PKCμ, and ROCK1, may participate in the mechanotransduction and modulation VSMC functions.  相似文献   
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Highly pathogenic avian influenza H5N1 virus clades 2.3.4, 2.3.2, and 7 are the dominant cocirculating H5N1 viruses in poultry in China. However, humans appear to be clinically susceptible mostly to the 2.3.4 virus clade. Here, we demonstrated that A549 cells and human macrophages infected with clade 2.3.4 viruses produced significantly more viruses than those infected with the other two clades. Likewise, clade 2.3.4-infected macrophages caused the most severe cellular damage and strongest proinflammatory response.  相似文献   
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Background

The main goal of our study was to investigate the implementation, prospects, and limits of marker imputation for quantitative genetic studies contrasting map-independent and map-dependent algorithms. We used a diversity panel consisting of 372 European elite wheat (Triticum aestivum L.) varieties, which had been genotyped with SNP arrays, and performed intensive simulation studies.

Results

Our results clearly showed that imputation accuracy was substantially higher for map-dependent compared to map-independent methods. The accuracy of marker imputation depended strongly on the linkage disequilibrium between the markers in the reference panel and the markers to be imputed. For the decay of linkage disequilibrium present in European wheat, we concluded that around 45,000 markers are needed for low cost, low-density marker profiling. This will facilitate high imputation accuracy, also for rare alleles. Genomic selection and diversity studies profited only marginally from imputing missing values. In contrast, the power of association mapping increased substantially when missing values were imputed.

Conclusions

Imputing missing values is especially of interest for an economic implementation of association mapping in breeding populations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1366-y) contains supplementary material, which is available to authorized users.  相似文献   
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Post-domestication selection refers to the artificial selection on the loci controlling important agronomic traits during the process of genetic improvement in a population. The maize genes Zfl1 and Zfl2, duplicate orthologs of Arabidopsis LEAFY, are key regulators in plant branching, inflorescence and flower development, and reproduction. In this study, the full gene sequences of Zfl1 and Zfl2 from 62 Chinese elite inbred lines were amplified to evaluate their nucleotide polymorphisms and haplotype diversities. A total of 254 and 192 variants that included SNPs and indels were identified from the full sequences of Zfl1 and Zfl2, respectively. Although most of the variants were found to be located in the non-coding regions, the polymorphisms of CDS sequences classified Zfl1 into 16 haplotypes encoding 16 different proteins and Zfl2 into 18 haplotypes encoding eight different proteins. The population of Huangzaosi and its derived lines showed statistically significant signals of post-domestication selection on the Zfl1 CDS sequences, as well as lower nucleotide polymorphism and haplotype diversity than the whole set. However, the Zfl2 locus was only selected for in the heterotic group Reid. Further evidence revealed that at least 17 recombination events contributed to the genetic and haplotype diversities at the Zfl1 locus and 16 recombination events at the Zfl2 locus.  相似文献   
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