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排序方式: 共有217条查询结果,搜索用时 46 毫秒
31.
Jennifer F. Knight Vanessa Y.C. Sung Elena Kuzmin Amber L. Couzens Danielle A. de Verteuil Colin D.H. Ratcliffe Paula P. Coelho Radia M. Johnson Payman Samavarchi-Tehrani Tina Gruosso Harvey W. Smith Wontae Lee Sadiq M. Saleh Dongmei Zuo Hong Zhao Marie-Christine Guiot Ryan R. Davis Jeffrey P. Gregg Morag Park 《Cell reports》2018,22(12):3191-3205
32.
33.
Robert S. Kawuki Morag Ferguson Maryke Labuschagne Liezel Herselman Dong-Jin Kim 《Molecular breeding : new strategies in plant improvement》2009,23(4):669-684
To monitor genetic diversity in the field it is important that it is measured accurately. Here, we elucidate the potential
of single nucleotide polymorphisms (SNPs) for measuring genetic diversity in cassava. The nature and frequency of SNPs was
characterised and their utility in genetic diversity assessment compared to that of simple sequence repeats (SSRs). This was
achieved by direct sequencing of amplicons in diverse cassava varieties. A total of 26 SNPs were identified from quality sequences
of nine genes, giving an estimated frequency of one SNP every 121 nucleotides. Nucleotide diversity ranged from 7.8 × 10−4 to 5.6 × 10−3. Average haplotype-based polymorphic information content (PIC = 0.414) was higher than for individual SNPs (PIC = 0.228).
The Mantel test indicated interdependence (r = 0.219; P < 0.001) between SNP and SSR genotypic data. Individual SNPs had lower PIC values than SSRs. For this reason larger numbers
of SNPs may be necessary to achieve the same level of discrimination among genotypes provided by SSRs. 相似文献
34.
35.
Sait M Clark EM Wheelhouse N Livingstone M Spalding L Siarkou VI Vretou E Smith DG Lainson FA Longbottom D 《Journal of bacteriology》2011,193(16):4276-4277
Chlamydophila abortus is a common cause of ruminant abortion. Here we report the genome sequence of strain LLG, which differs genotypically and phenotypically from the wild-type strain S26/3. Genome sequencing revealed differences between LLG and S26/3 to occur in pseudogene content, in transmembrane head/inc family proteins, and in biotin biosynthesis genes. 相似文献
36.
Beer NL van de Bunt M Colclough K Lukacs C Arundel P Chik CL Grimsby J Ellard S Gloyn AL 《The Journal of biological chemistry》2011,286(21):19118-19126
Type 2 diabetes is a global problem, and current ineffective therapeutic strategies pave the way for novel treatments like small molecular activators targeting glucokinase (GCK). GCK activity is fundamental to beta cell and hepatocyte glucose metabolism, and heterozygous activating and inactivating GCK mutations cause hyperinsulinemic hypoglycemia (HH) and maturity onset diabetes of the young (MODY) respectively. Over 600 naturally occurring inactivating mutations have been reported, whereas only 13 activating mutations are documented to date. We report two novel GCK HH mutations (V389L and T103S) at residues where MODY mutations also occur (V389D and T103I). Using recombinant proteins with in vitro assays, we demonstrated that both HH mutants had a greater relative activity index than wild type (6.0 for V389L, 8.4 for T103S, and 1.0 for wild type). This was driven by an increased affinity for glucose (S(0.5), 3.3 ± 0.1 and 3.5 ± 0.1 mm, respectively) versus wild type (7.5 ± 0.1 mm). Correspondingly, the V389D and T103I MODY mutants had markedly reduced relative activity indexes (<0.1). T103I had an altered affinity for glucose (S(0.5), 24.9 ± 0.6 mm), whereas V389D also exhibited a reduced affinity for ATP and decreased catalysis rate (S(0.5), 78.6 ± 4.5 mm; ATP(K(m)), 1.5 ± 0.1 mm; K(cat), 10.3 ± 1.1s(-1)) compared with wild type (ATP(K(m)), 0.4 ± <0.1; K(cat), 62.9 ± 1.2). Both Thr-103 mutants showed reduced inhibition by the endogenous hepatic inhibitor glucokinase regulatory protein. Molecular modeling demonstrated that Thr-103 maps to the allosteric activator site, whereas Val-389 is located remotely to this position and all other previously reported activating mutations, highlighting α-helix 11 as a novel region regulating GCK activity. Our data suggest that pharmacological manipulation of GCK activity at locations distal from the allosteric activator site is possible. 相似文献
37.
Jesse Hudson Jacqueline R. Ha Valerie Sabourin Ryuhjin Ahn Rachel La Selva Julie Livingstone Lauren Podmore Jennifer Knight Laura Forrest Nicole Beauchemin Michael Hallett Morag Park Josie Ursini-Siegel 《Molecular and cellular biology》2014,34(19):3689-3701
Breast cancers are stratified into distinct subtypes, which influence therapeutic responsiveness and patient outcome. Patients with luminal breast cancers are often associated with a better prognosis relative to that with other subtypes. However, subsets of patients with luminal disease remain at increased risk of cancer-related death. A critical process that increases the malignant potential of breast cancers is the epithelial-to-mesenchymal transition (EMT). The p66ShcA adaptor protein stimulates the formation of reactive oxygen species in response to stress stimuli. In this paper, we report a novel role for p66ShcA in inducing an EMT in HER2+ luminal breast cancers. p66ShcA increases the migratory properties of breast cancer cells and enhances signaling downstream of the Met receptor tyrosine kinase in these tumors. Moreover, Met activation is required for a p66ShcA-induced EMT in luminal breast cancer cells. Finally, elevated p66ShcA levels are associated with the acquisition of an EMT in primary breast cancers spanning all molecular subtypes, including luminal tumors. This is of high clinical relevance, as the luminal and HER2 subtypes together comprise 80% of all newly diagnosed breast cancers. This study identifies p66ShcA as one of the first prognostic biomarkers for the identification of more aggressive tumors with mesenchymal properties, regardless of molecular subtype. 相似文献
38.
Morag F Dick Jennifer Hurford Sha Lei Anne-Mari Mustonen Petteri Nieminen Kirsti Rouvinen-Watt 《Acta veterinaria Scandinavica》2014,56(1):1-9
Background
Rapid body fat mobilization, obesity, and an inadequate supply of n-3 polyunsaturated fatty acids (PUFA) have been suggested to play roles in the etiology of fatty liver in the American mink (Neovison vison). This study examined the effects of feeding intensity and dietary fat source on fatty liver induced by fasting. In a multi-factorial design, 3 different fat sources (herring oil, rich in n-3 PUFA, soya oil, rich in n-6 PUFA, and canola oil, rich in n-9 monounsaturated fatty acids) were fed to mink at a low and high feeding intensity for 10 weeks, followed by an overnight or a 5-day fasting treatment to induce fatty liver.Results
Fasting led to the development of fatty liver with increased severity in the mink fed at the high feeding intensity. The herring oil diet, high in long-chain n-3 PUFA, was found to decrease the severity of fatty liver in the mink at the high feeding intensity.Conclusion
Preventing excessive weight gain and increasing dietary intake of n-3 long-chain PUFA may help prevent excessive lipid accumulation during prolonged periods of fasting or inappetence by promoting hepatic fatty acid oxidation. 相似文献39.
Predictions of stream nutrient and sediment yield changes following restoration of forested riparian buffers 总被引:6,自引:1,他引:6
Stephanie M. Parkyn Robert J. Davies-Colley A. Bryce Cooper Morag J. Stroud 《Ecological Engineering》2005,24(5):551-558
Riparian tree planting is widely recognised as a means to improve water quality and stream habitat. However, shading of riparian pasture grasses can lead to channel widening, and riparian shade may limit the growth of macrophytes and algae that assimilate dissolved nutrients from the water column. We investigated concerns that riparian management could lead to increased yields of nutrients and sediments through a conceptual modelling exercise. A simple model of the trade-off between interception of nutrients in runoff by forest buffers versus reduction of in-stream uptake due to shade, predicted that a buffer strip alongside a small headwater stream would reduce nutrient export, while a buffer strip instigated as an isolated patch alongside a larger stream (c. >2.5 km2 upstream catchment size) would increase nutrient export, as the relative amount of nutrients trapped by the buffer decreases as the nutrient load present in the stream water increases. However, in these larger streams with width exceeding approximately 6 m, sufficient light may reach the streambed for plant and algal growth, which in turn would promote instream nutrient processing. At the peak of streambank erosion after planting, predicted total sediment yield (hillslope plus bank sources) was appreciably higher than the hillslope pasture yield, but sediment yield stabilised c. 35–40 years after planting. When planting was extended over 40 years in the model, the sediment yield never exceeded that in pasture before planting. This conceptual modelling exercise shows that riparian tree planting programmes should commence in the headwaters and progress downstream to avoid nutrient yield increases. Significant sediment yield from bank stored sediment of small streams can be expected until the channel reaches the more stable, original forested width, but progressive planting may decrease the peak loads of sediment. 相似文献
40.
King Timothy P.; Begbie Robert; Slater Diane; McFadyen Morag; Thom Amanda; Kelly Denise 《Glycobiology》1995,5(5):525-534
Affinity cytochemistry and biochemistry revealed distinctivetemporal changes in the expression of sialylated and compositionallyrelated membrane glycoconjugates in the pig small intestinebetween birth and weaning. The expression of membrane NeuAc2,6moieties, recognized by Sambucus nigra agglutinin-1, was highin newborn pigs, declined slightly during sucking and was verylow in weaned animals. Conversely, the expression of membraneNeuAc2r3 moieties, recognized by Maackia amurensis agglutinin-2,was low at birth but higher in sucking and weaned animals. Histobloodgroup O- and A-antigen expression was first detected in a minorityof sucking pigs, but was evident in all weaned pigs examined.Lactase glycoforms were isolated from solubilized microvillarmembranes of newborn and weaned pigs. The newborn (predominantly2,6-sialylated) and weaned (predominantly 1,2-fucosylated) glycoformsexhibited similar specific activity, indicating that postnatallactase decline in the pig intestine is unrelated to temporalchanges in membrane sialylation and fucosylation. fucosylation lactase lectins intestine sialylation 相似文献