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941.
942.
Background
Butterflies and moths are emerging as model organisms in genetics and evolutionary studies. The family Hesperiidae (skippers) was traditionally viewed as a sister to other butterflies based on its moth-like morphology and darting flight habits with fast wing beats. However, DNA studies suggest that the family Papilionidae (swallowtails) may be the sister to other butterflies including skippers. The moth-like features and the controversial position of skippers in Lepidoptera phylogeny make them valuable targets for comparative genomics.Results
We obtained the 310 Mb draft genome of the Clouded Skipper (Lerema accius) from a wild-caught specimen using a cost-effective strategy that overcomes the high (1.6 %) heterozygosity problem. Comparative analysis of Lerema accius and the highly heterozygous genome of Papilio glaucus revealed differences in patterns of SNP distribution, but similarities in functions of genes that are enriched in non-synonymous SNPs. Comparison of Lepidoptera genomes revealed possible molecular bases for unique traits of skippers: a duplication of electron transport chain components could result in efficient energy supply for their rapid flight; a diversified family of predicted cellulases might allow them to feed on cellulose-enriched grasses; an expansion of pheromone-binding proteins and enzymes for pheromone synthesis implies a more efficient mate-recognition system, which compensates for the lack of clear visual cues due to the similarities in wing colors and patterns of many species of skippers. Phylogenetic analysis of several Lepidoptera genomes suggested that the position of Hesperiidae remains uncertain as the tree topology varied depending on the evolutionary model.Conclusion
Completion of the first genome from the family Hesperiidae allowed comparative analyses with other Lepidoptera that revealed potential genetic bases for the unique phenotypic traits of skippers. This work lays the foundation for future experimental studies of skippers and provides a rich dataset for comparative genomics and phylogenetic studies of Lepidoptera.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1846-0) contains supplementary material, which is available to authorized users. 相似文献943.
944.
Follicle‐stimulating hormone promotes age‐related endometrial atrophy through cross‐talk with transforming growth factor beta signal transduction pathway 下载免费PDF全文
Dan Zhang Jingyi Li Gufeng Xu Runjv Zhang Chengliang Zhou Yeqing Qian Yifeng Liu Luting Chen Bo Zhu Xiaoqun Ye Fan Qu Xinmei Liu Shuai Shi Weijun Yang Jianzhong Sheng Hefeng Huang 《Aging cell》2015,14(2):284-287
It is widely believed that endometrial atrophy in postmenopausal women is due to an age‐related reduction in estrogen level. But the role of high circulating follicle‐stimulating hormone (FSH) in postmenopausal syndrome is not clear. Here, we explored the role of high circulating FSH in physiological endometrial atrophy. We found that FSH exacerbated post‐OVX endometrial atrophy in mice, and this effect was ameliorated by lowering FSH with Gonadotrophin‐releasing hormone agonist (GnRHa). In vitro, FSH inhibited endometrial proliferation and promoted the apoptosis of primary cultured endometrial cells in a dose‐dependent manner. In addition, upregulation of caspase3, caspase8, caspase9, autophagy‐related proteins (ATG3, ATG5, ATG7, ATG12 and LC3) and downregulation of c‐Jun were also observed in endometrial adenocytes. Furthermore, smad2 and smad3 showed a time‐dependent activation in endometrial cells which can be partly inhibited by blocking the transforming growth factor beta receptor II (TβRII). In conclusion, FSH regulated endometrial atrophy by affecting the proliferation, autophagy and apoptosis of endometrial cells partly through activation of the transforming growth factor beta (TGFβ) pathway. 相似文献
945.
Runbi Ji Bin Zhang Xu Zhang Jianguo Xue Xiao Yuan Yongmin Yan Mei Wang Wei Zhu Hui Qian Wenrong Xu 《Cell cycle (Georgetown, Tex.)》2015,14(15):2473-2483
Mesenchymal stem cells (MSCs) play an important role in chemoresistance. Exosomes have been reported to modify cellular phenotype and function by mediating cell-cell communication. In this study, we aimed to investigate whether exosomes derived from MSCs (MSC-exosomes) are involved in mediating the resistance to chemotherapy in gastric cancer and to explore the underlying molecular mechanism. We found that MSC-exosomes significantly induced the resistance of gastric cancer cells to 5-fluorouracil both in vivo and ex vivo. MSC-exosomes antagonized 5-fluorouracil-induced apoptosis and enhanced the expression of multi-drug resistance associated proteins, including MDR, MRP and LRP. Mechanistically, MSC-exosomes triggered the activation of calcium/calmodulin-dependent protein kinases (CaM-Ks) and Raf/MEK/ERK kinase cascade in gastric cancer cells. Blocking the CaM-Ks/Raf/MEK/ERK pathway inhibited the promoting role of MSC-exosomes in chemoresistance. Collectively, MSC-exosomes could induce drug resistance in gastric cancer cells by activating CaM-Ks/Raf/MEK/ERK pathway. Our findings suggest that MSC-exosomes have profound effects on modifying gastric cancer cells in the development of drug resistance. Targeting the interaction between MSC-exosomes and cancer cells may help improve the efficacy of chemotherapy in gastric cancer. 相似文献
946.
Kong X Zhang C Jin X Wu X Zhang S Zhong Z Feng Q Liu T Yuan H 《BioFactors (Oxford, England)》2011,37(4):323-327
The objective of this study is to observe the effect of high-mobility group protein B1 A Box (HMGB1 A) box on lung injury in mice with acute pancreatitis and its effect on the level of high-mobility group protein B1 (HMGB1) in lung, to explore the mechanism. A total of 60 male Institute of Cancer Research mice were randomly divided into control group (n = 30) and treatment group (n = 30). Severe acute pancreatitis mice model was induced by 20% L-Arg intraperitoneal injection. The recombination HMGB1 A box was used in treatment after modeling. All the mice were killed under anesthesia at 24 and 48 h after the modeling injection. The level of HMGB1 and activity of myeloperoxidase (MPO) in lung were measured. The pathological changes of lung were observed. The level of HMGB1 in lung of A box treatment group decreased more significantly 24 h and 48 h after modeling compared with control group. The activity of MPO in lung of A box treatment group decreased more significantly 24 h after modeling compared with control group. The lung tissue pathologic score of A box treatment group decreased more significantly 48 h after modeling compared with control group. HMGB1 expression levels in the lungs were positively related to histological score of injured lung in acute pancreatitis. It indicates that HMGB1 A box is remarkably protective to lung injury induced by acute pancreatitis. 相似文献
947.
948.
Simultaneous detection of multianalytes associated with a particular cancer is beneficial for disease diagnosis. Here, a facile immunosensing strategy was designed to allow simultaneous electrochemical detection of dual proteins, in a single run. CdSe and PbS water-soluble quantum dots (QDs) were prepared and coated on monodisperse silica nanoparticles as labels for proteins detection. Rabbit immunoglobulin G antigen (IgG) and carcinoembryonic antigen (CEA) were chosen as model proteins for analysis. After a typical sandwich immunoassay, CdSe and PbS QDs labels were introduced onto the Au substrates' surface, which were then dissolved and could be simultaneously monitored by square-wave-voltammetric (SWV) stripping measurements. Under selected conditions, IgG and CEA could be assayed in the ranges of 0.05-40 ng mL(-1) and 0.05-25 ng mL(-1), respectively. The proposed method possessed high sensitivity, good precision, and satisfactory reproducibility and regeneration. 相似文献
949.
Effect of lignocellulosic inhibitory compounds on growth and ethanol fermentation of newly-isolated thermotolerant Issatchenkia orientalis 总被引:1,自引:0,他引:1
A newly isolated thermotolerant ethanologenic yeast strain, Issatchenkia orientalis IPE 100, was able to produce ethanol with a theoretical yield of 85% per g of glucose at 42 °C. Ethanol production was inhibited by furfural, hydroxymethylfurfural and vanillin concentrations above 5.56 g L−1, 7.81 g L−1, and 3.17 g L−1, respectively, but the strain was able to produce ethanol from enzymatically hydrolyzed steam-exploded cornstalk with 93.8% of theoretical yield and 0.91 g L−1 h−1 of productivity at 42 °C. Therefore, I. orientalis IPE 100 is a potential candidate for commercial lignocelluloses-to-ethanol production. 相似文献
950.
Acid tolerance of an acid mine drainage bioremediation system based on biological sulfate reduction 总被引:1,自引:0,他引:1
The acid tolerance response of an AMD bioremediation system based on sulfate reduction was investigated. Efficient sulfate reduction was observed with a maximum sulfate reduction rate of 12.3±0.8 mg L(-1) d(-1) and easily available organic carbon was released during high acid treatment with an initial pH of 2.0. The rapid increase in sulfate reduction was observed when the extreme acid treatment with an initial pH of 1.0 was stopped. Column experiment on acid shock showed that efficient sulfate reduction was maintained while precipitation of Cu or Zn still occurred during extreme or high acid shock. More than 98% of Cu and 85% of Zn were removed in the high acid column experiment with influent pH of 2.0. The majority bacteria in the remediation system used for high acid drainage belonged to genera Clostridiaceae, Eubacterium, Pseudobutyrivibrio, and Clostridium. These findings showed high acid tolerance of the straw remediation system. 相似文献