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81.
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83.
INCENP is required for proper targeting of Survivin to the centromeres and the anaphase spindle during mitosis 总被引:37,自引:0,他引:37
Three lines of investigation have suggested that interactions between Survivin and the chromosomal passenger proteins INCENP and Aurora-B kinase may be important for mitotic progression. First, interference with the function of Survivin/BIR1, INCENP, or Aurora-B kinase leads to similar defects in mitosis and cytokinesis [1-7] (see [8] for review). Second, INCENP and Aurora-B exist in a complex in Xenopus eggs [9] and in mammalian cultured cells [7]. Third, interference with Survivin or INCENP function causes Aurora-B kinase to be mislocalized in mitosis in both C. elegans and vertebrates [5, 7, 9]. Here, we provide evidence that Survivin, Aurora-B, and INCENP interact physically and functionally. Direct visualization of Survivin-GFP in mitotic cells reveals that it localizes identically to INCENP and Aurora-B. Survivin binds directly to both Aurora-B and INCENP in yeast two-hybrid and in vitro pull-down assays. The in vitro interaction between Survivin and Aurora-B is extraordinarily stable in that it resists 3 M NaCl. Finally, Survivin and INCENP interact functionally in vivo; in cells in which INCENP localization is disrupted, Survivin adheres to the chromosomes and no longer concentrates at the centromeres or transfers to the anaphase spindle midzone. Our data provide the first biochemical evidence that Survivin can interact directly with members of the chromosomal passenger complex. 相似文献
84.
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Background
Molluscs are the most diverse marine phylum and this high diversity has resulted in considerable taxonomic problems. Because the number of species in Canadian oceans remains uncertain, there is a need to incorporate molecular methods into species identifications. A 648 base pair segment of the cytochrome c oxidase subunit I gene has proven useful for the identification and discovery of species in many animal lineages. While the utility of DNA barcoding in molluscs has been demonstrated in other studies, this is the first effort to construct a DNA barcode registry for marine molluscs across such a large geographic area.Methodology/Principal Findings
This study examines patterns of DNA barcode variation in 227 species of Canadian marine molluscs. Intraspecific sequence divergences ranged from 0–26.4% and a barcode gap existed for most taxa. Eleven cases of relatively deep (>2%) intraspecific divergence were detected, suggesting the possible presence of overlooked species. Structural variation was detected in COI with indels found in 37 species, mostly bivalves. Some indels were present in divergent lineages, primarily in the region of the first external loop, suggesting certain areas are hotspots for change. Lastly, mean GC content varied substantially among orders (24.5%–46.5%), and showed a significant positive correlation with nearest neighbour distances.Conclusions/Significance
DNA barcoding is an effective tool for the identification of Canadian marine molluscs and for revealing possible cases of overlooked species. Some species with deep intraspecific divergence showed a biogeographic partition between lineages on the Atlantic, Arctic and Pacific coasts, suggesting the role of Pleistocene glaciations in the subdivision of their populations. Indels were prevalent in the barcode region of the COI gene in bivalves and gastropods. This study highlights the efficacy of DNA barcoding for providing insights into sequence variation across a broad taxonomic group on a large geographic scale. 相似文献86.
The amount of wounding during routine culling is an important factor in the welfare of wild deer. Little information exists on factors determining shooting accuracy and wounding rates under field conditions in the UK. In this study, 102 anonymous stalkers collected data on the outcomes and circumstances of 2281 shots. Using hot-deck imputation and generalised linear mixed modelling, we related the probability that a shot hit its target, and the probability that the shot killed the deer if it was hit, to 28 variables describing the circumstances of the shot. Overall, 96% of deer were hit, of which 93% were killed outright. A reduced probability of hitting the target was associated with an uncomfortable firing position, too little time available, shooting off elbows or freehand, taking the head or upper neck as point of aim, a heavily obscured target, a distant target, shooting at females, lack of shooting practice and a basic (or no) stalker qualification. An increase in the likelihood of wounding was associated with an uncomfortable firing position, shooting with insufficient time, a distant target (only when time was not sufficient), a bullet weight below 75 grains, a target concealed in thicket or on the move and an area rarely stalked. To maximise stalking success and deer welfare, we recommend that stalkers ensure a comfortable firing position, use a gun rest, aim at the chest, use bullets heavier than 75 grains, avoid taking a rushed shot, shoot a distant animal only if there is plenty of time, fire only when the target is stationary, avoid shooting at an obscured animal, take care when the ground is unfamiliar, and do shooting practice at least once a month. The high miss rate of basic-level stalkers suggests that training should include additional firing practice under realistic shooting conditions. 相似文献
87.
James R. R. Whittle Adam K. Wheatley Lan Wu Daniel Lingwood Masaru Kanekiyo Steven S. Ma Sandeep R. Narpala Hadi M. Yassine Gregory M. Frank Jonathan W. Yewdell Julie E. Ledgerwood Chih-Jen Wei Adrian B. McDermott Barney S. Graham Richard A. Koup Gary J. Nabel 《Journal of virology》2014,88(8):4047-4057
88.
The effect of the gaseous metabolites of onePseudomonas fluorescens culture on the attachment of cells of anotherP. fluorescens culture to glass was studied. Gaseous metabolites increased the number of unattached cells by 10–30% and the mean residence
time of cells attached to glass by 100%. These effects were presumably due to the yet unidentified compound, which we called
volatile antiadhesin. This compound could be adsorbed by activated charcoal and HAYESEP-Q adsorbent. 相似文献
89.
David R. Armstrong John E. Davies Neil Feeder Elinor Lamb John J. Longridge Jeremy M. Rawson Ronald Snaith Andrew E. H. Wheatley 《Journal of molecular modeling》2000,6(2):234-247
Reaction of o-mercaptopyridine (o-MPH) and trithiocyanuric acid (TTCyH3) with one equivalent of BunLi in the presence of HMPA yields the mono-lithiated salts MPLi.HMPA (1) and TTCyH2Li.2HMPA (2) respectively, which have been characterised by NMR spectroscopy and X-ray crystallography. Reaction of three equivalents of BunLi with anhydrous TTCyH3 in THF yields the tri-lithiated species TTCyLi3.4THF (3). In all three compounds the lithium centres have N,S-bridged coordination modes. Whereas 1 is dimeric in the solid state, 2 has an unusual monomeric structure and 3, which is a very rare example of a structurally characterised tri-lithiated compound, has an unprecedented polymeric structure incorporating (NCSLi)
n
(n = 1, 2) rings. The structural diversities displayed by 1 and 2 have been probed, and thereby in part rationalised, by ab initio (6-31G*/RHF, 6-31G**/RHF and 6-31G*/MP2 levels) MO calculations on both their thio-keto and thiol isomers and on their uncomplexed and complexed lithiated derivatives. In particular, the optimised structures predict and reproduce the N,S-bridging coordination modes found for lithium and explain why structure 1 is dimeric whereas 2 is monomeric.Electronic Supplementary Material available. 相似文献
90.
O. Monroy K. A. Johnson A. D. Wheatley F. Hawkes M. Caine 《Bioresource technology》1994,50(3):243-251
Results are presented from a pilot scale (4·3 m3) upflow anaerobic filter for the treatment of the wastewater from ice-cream manufacture. The reactor was completely mixed by gas production but the solids or sludge held within the reactor were shown to be affected by the liquid velocities. The reactor was subject to a number of organic and hydraulic shocks and this reduced the consistency of COD removal. Daily loading rates varied from 0 to 18 kg COD/m3/day but with an average load of 5·5 kg/m3/day the mean COD removal was 70%. This was compared with previous work and shown to be a typical performance for an anaerobic filter. Alkalinity and carboxylic acid data are also presented and were within the normal, stable, operating range. Previous research on the anaerobic treatment of industrial effluents has shown alkalinity to be the most important factor controlling reliability. 相似文献