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61.
A DNA barcode library for Germany′s mayflies,stoneflies and caddisflies (Ephemeroptera,Plecoptera and Trichoptera)
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Jérôme Morinière Lars Hendrich Michael Balke Arne J. Beermann Tobias König Monika Hess Stefan Koch Reinhard Müller Florian Leese Paul D. N. Hebert Axel Hausmann Christoph D. Schubart Gerhard Haszprunar 《Molecular ecology resources》2017,17(6):1293-1307
Mayflies, stoneflies and caddisflies (Ephemeroptera, Plecoptera and Trichoptera) are prominent representatives of aquatic macroinvertebrates, commonly used as indicator organisms for water quality and ecosystem assessments. However, unambiguous morphological identification of EPT species, especially their immature life stages, is a challenging, yet fundamental task. A comprehensive DNA barcode library based upon taxonomically well‐curated specimens is needed to overcome the problematic identification. Once available, this library will support the implementation of fast, cost‐efficient and reliable DNA‐based identifications and assessments of ecological status. This study represents a major step towards a DNA barcode reference library as it covers for two‐thirds of Germany's EPT species including 2,613 individuals belonging to 363 identified species. As such, it provides coverage for 38 of 44 families (86%) and practically all major bioindicator species. DNA barcode compliant sequences (≥500 bp) were recovered from 98.74% of the analysed specimens. Whereas most species (325, i.e., 89.53%) were unambiguously assigned to a single Barcode Index Number (BIN) by its COI sequence, 38 species (18 Ephemeroptera, nine Plecoptera and 11 Trichoptera) were assigned to a total of 89 BINs. Most of these additional BINs formed nearest neighbour clusters, reflecting the discrimination of geographical subclades of a currently recognized species. BIN sharing was uncommon, involving only two species pairs of Ephemeroptera. Interestingly, both maximum pairwise and nearest neighbour distances were substantially higher for Ephemeroptera compared to Plecoptera and Trichoptera, possibly indicating older speciation events, stronger positive selection or faster rate of molecular evolution. 相似文献
62.
CD36 is a fatty acid translocase in striated muscle cells and cardiomyocytes. Some study suggested that alterations in CD36 gene may be associated with coronary artery disease (CAD) risk. The aim of the current study was to compare the frequency of CD36 variants in region encoding lipid-binding domain in Caucasian patients with early-onset CAD, no-CAD adult controls and neonates. The study group comprised 100 patients with early onset CAD. The genetic control groups were 306 infants and 40 no-CAD adults aged over 70 years. Exons 4, 5 and 6 including fragments of flanking introns were studied using the denaturing high-performance liquid chromatography technique and direct sequencing. Changes detected in analyzed fragment of CD36: IVS3-6 T/C (rs3173798), IVS4-10 G/A (rs3211892), C311T (Thr104Ile, not described so far) in exon 5, G550A (Asp184Asn, rs138897347), C572T (Pro191Leu, rs143150225), G573A (Pro191Pro, rs5956) and A591T (Thr197Thr, rs141680676) in exon 6. No significant differences in the CD36 genotype, allele and haplotype frequencies were found between the three groups. Only borderline differences (p = 0.066) were found between early onset CAD patients and newborns in the frequencies of 591T allele (2.00% vs 0.50%) and CGCGCGT haplotype (2.00% vs 0.50%) with both IVS3-6C and 591T variant alleles. In conclusion, CD36 variants: rs3173798, rs3211892, rs138897347, rs5956, rs143150225 rs141680676 and C311T do not seem to be involved in the risk of early-onset CAD in Caucasian population. 相似文献
63.
Biochemical studies have demonstrated that dihydroorotate dehydrogenase (DHOdehase; EC 1.3.3.1 or 1.3.99.11) is the sole enzyme of de novo pyrimidine synthesis in mitochondria, whereas the rest of the pathway takes place in the cytosol. The dehydrogenation of dihydroorotate to orotate is linked to the respiratory chain via ubiquinone. In this study, we show for the first time the ultrastructural localization of DHOdehase. Since the purified enzyme was found to act both as dehydrogenase and as oxidase, the cerium capture technique for detecting enzymatically generated hydrogen peroxide could be applied to pin-point the in situ activity of DHOdehase oxidase in mitochondria of rat heart and kidney cortex. Cerium perhydroxide as the final reaction product was detected predominantly in the matrix with some focal condensation along the inner membrane, but not in the intermembrane space. From this pattern of localization, it is concluded that the active site of the membrane-bound enzyme could face the mitochondrial matrix similar to succinate dehydrogenase. The reliability of the applied method for the demonstration of DHOdehase oxidase was demonstrated by the addition of Brequinar sodium to the incubation medium. This quinoline-carboxylic acid derivative is a potent inhibitor of DHOdehase and has proven anti-proliferative activity. The present observations do not ascertain whether the oxidase is permanently active as a constant portion of the enzyme in vivo, similar to xanthine oxidase/dehydrogenase. However, DHOdehase should be considered as a source of radical oxygen species under pathophysiological conditions. 相似文献
64.
65.
Transcriptome profiling of immune tissues reveals habitat‐specific gene expression between lake and river sticklebacks
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66.
This study involved the development of formaldehyde-treated, deseeded sunflower head waste–based biosorbent (FSH) for the biosorption of Cr(VI) from aqueous solution and industrial wastewater. Batch-mode experiments were conducted to determine the kinetics, sorption isotherms, effect of pH, initial Cr(VI) concentration, biosorbent dose, and contact time. The results demonstrated that FSH can sequester Cr(VI) from the aqueous solution. The maximum sorption occurred at pH = 2.0, biosorbent dose = 4.0 g/L, concentration of 100 mg/L at 25°C at 180 rpm after 2 h contact time. The FSH had an adsorption capacity of 7.85 mg/g for Cr(VI) removal at pH 2.0. The rate of adsorption was rapid, and equilibrium was attained within 2 h. The equilibrium sorption data fitted the Langmuir isotherm model, which was further confirmed by the chi-square test. 相似文献
67.
Christoph Heier Ulrike Taschler Maja Radulovic Philip Aschauer Thomas O. Eichmann Susanne Grond Heimo Wolinski Monika Oberer Rudolf Zechner Sepp D. Kohlwein Robert Zimmermann 《The Journal of biological chemistry》2016,291(22):11865-11875
Fatty acid ethyl esters (FAEEs) are non-oxidative metabolites of ethanol that accumulate in human tissues upon ethanol intake. Although FAEEs are considered as toxic metabolites causing cellular dysfunction and tissue damage, the enzymology of FAEE metabolism remains poorly understood. In this study, we used a biochemical screen in Saccharomyces cerevisiae to identify and characterize putative hydrolases involved in FAEE catabolism. We found that Yju3p, the functional orthologue of mammalian monoacylglycerol lipase (MGL), contributes >90% of cellular FAEE hydrolase activity, and its loss leads to the accumulation of FAEE. Heterologous expression of mammalian MGL in yju3Δ mutants restored cellular FAEE hydrolase activity and FAEE catabolism. Moreover, overexpression or pharmacological inhibition of MGL in mouse AML-12 hepatocytes decreased or increased FAEE levels, respectively. FAEEs were transiently incorporated into lipid droplets (LDs) and both Yju3p and MGL co-localized with these organelles. We conclude that the storage of FAEE in inert LDs and their mobilization by LD-resident FAEE hydrolases facilitate a controlled metabolism of these potentially toxic lipid metabolites. 相似文献
68.
Activation of the RalGEF/Ral pathway promotes prostate cancer metastasis to bone 总被引:1,自引:0,他引:1
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Yin J Pollock C Tracy K Chock M Martin P Oberst M Kelly K 《Molecular and cellular biology》2007,27(21):7538-7550
A hallmark of metastasis is organ specificity; however, little is known about the underlying signaling pathways responsible for the colonization and growth of tumor cells in target organs. Since tyrosine kinase receptor activation is frequently associated with prostate cancer progression, we have investigated the role of a common signaling intermediary, activated Ras, in prostate cancer metastasis. Three effector pathways downstream of Ras, Raf/extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase, and Ral guanine nucleotide exchange factors (RalGEFs), were assayed for their ability to promote the metastasis of a tumorigenic, nonmetastatic human prostate cancer cell line, DU145. Oncogenic Ras promoted the metastasis of DU145 to multiple organs, including bone and brain. Activation of the Raf/ERK pathway stimulated metastatic colonization of the brain, while activation of the RalGEF pathway led to bone metastases, the most common organ site for prostate cancer metastasis. In addition, loss of RalA in the metastatic PC3 cell line inhibited bone metastasis but did not affect subcutaneous tumor growth. Loss of Ral appeared to suppress expansive growth of prostate cancer cells in bone, whereas homing and initial colonization were less affected. These data extend our understanding of the functional roles of the Ral pathway and begin to identify signaling pathways relevant for organ-specific metastasis. 相似文献
69.
The growth of the Spodoptera frugiperda cell line Sf9 was studied in batch and continuous culture. The results of batch cultivations showed that glucose was the preferred energy and carbon source limiting the cell density in both TNM-FH and IPL-41 media. Continuous culture using IPL-41-based feeding medium with different glucose (2.5, 5 and 10 g l−1) and yeast extract concentrations (4, 8 and 16 g l−1) showed that in serum-supplemented medium the maximum cell density was limited by glucose and yeast extract concentration. The transition to glucose limitation caused a decrease in growth rate and viability. A high cell density culture (18 × 106 ml−1) was obtained using a glucose concentration of 10 g l−1 and a yeast extract concentration of 8 g l−1 in the feeding medium. A yeast extract concentration of 16 g l−1 inhibited growth. Unlike mammalian cell cultures, lactate, alanine and ammonia were not involved in growth inhibition. Lactate did not accumulate under aerobic conditions. Ammonia accumulation, if observed, was insignificant. The level of alanine synthesized and excreted into the culture medium never reached an inhibitory level. During glucose limitation alanine did not accumulate and ammonia was released. However, even in the presence of glucose significant amounts of Asp, Glu, Gln, Asn, Ser, Arg and Met were utilized for energy production. The amino groups of these amino acids were transferred to pyruvate or used for nucleic acid synthesis and excreted in the form of alanine into the culture medium. The consumption of His, Lys, Thr, Gly, Val, Leu, Phe, Tyr, Trp and Ile by growing Sf-9 cells was almost equal to their concentration in the biomass. 相似文献
70.
Transgelin is a protein reported to be a marker of several cancers. However, previous studies have shown both up‐ and down‐regulation of transgelin in tumors when compared with non‐tumor tissues and the mechanisms whereby transgelin may affect the development of cancer remain largely unknown. Transgelin is especially abundant in smooth muscle cells and is associated with actin stress fibers. These contractile structures participate in cell motility, adhesion, and the maintenance of cell morphology. Here, the role of transgelin in breast cancer is focused on. Initially, the effects of transgelin on cell migration of the breast cancer cell lines, BT 549 and PMC 42, is studied. Interestingly, transgelin silencing increased the migration of PMC 42 cells, but decreased the migration of BT 549 cells. To clarify these contradictory results, the changes in protein abundances after transgelin silencing in these two cell lines are analyzed using quantitative proteomics. The results confirmed the role of transgelin in the migration of BT 549 cells and suggest the involvement of transgelin in apoptosis and small molecule biochemistry in PMC 42 cells. The context‐dependent function of transgelin reflects the different molecular backgrounds of these cell lines, which differ in karyotypes, mutation statuses, and proteome profiles. 相似文献