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101.
Sarah C. Crews Alberto R. Puente-Rolón Elliot Rutstein Rosemary G. Gillespie 《Molecular phylogenetics and evolution》2010,54(3):970-983
The role of the landscape in structuring populations has been the focus of numerous studies, in particular, the extent to which islands provide opportunities for isolation, and the consistency of such an effect across lineages. The current study examines this phenomenon using a series of relatively widespread taxa, all within a single genus of spiders, Selenops. We focus on the Caribbean Islands and adjacent Mesoamerican mainland to examine how the islands per se dictate structure across lineages. We use molecular genetic data from mitochondrial and nuclear genes to examine the population structure of seven species of Selenops. Comparisons are made between species found in the Greater Antilles, Lesser Antilles, and adjacent mainland. Results indicate that geography has little effect on the population structure of mainland species. In contrast, population structure appears to be partitioned by island in the insular Caribbean. Within islands, the amount of population structure for each species is variable and may be dictated more by ecological or demographic parameters, rather than geographic location. The overall conclusion is that the extent to which a given lineage is structured is highly variable across species, with this variability overwhelming any general signal of geographical isolation. 相似文献
102.
Colleen R. Alma David R. Gillespie Bernard D. Roitberg Mark S. Goettel 《Journal of Insect Behavior》2010,23(2):90-99
The nature and severity of intraguild interactions between predators and entomopathogens will be determined, in part, by a
combination of threat of infection, and avoidance of that threat by the predator. We determined the threat of infection posed
by the entomopathogen, Paecilomyces fumosoroseus (as PFR-97™) to the generalist predator, Dicyphus hesperus. We then asked if D. hesperus displays behavioral avoidance of infection while foraging for whitefly nymphs at different stages of infection by the pathogen.
When exposed to leaf surfaces treated with the pathogen, 28% of adult female predators died due to infection. Consumption
of Ephestia kuehniella eggs by surviving predators over 6 d was significantly reduced, suggesting effects of a sublethal infection. Whitefly nymphs
that had been treated with P. fumosoroseus 3 d prior were acceptable as prey to D. hesperus but whitefly nymphs that had been treated with P. fumosoroseus 5 days prior were not. When foraging for whitefly nymphs, adult D. hesperus females rejected infected nymphs 96% of the time, compared to 39% of non-infected nymphs. Paecilomyces fumosoroseus therefore presents a measurable threat to D. hesperus through mortality and reduced prey consumption. Dicyphus hesperus does not avoid initial contact with infected prey but does not feed on such prey. The mechanism underlying these rejections
could be due to either avoidance of infection or rejection of prey already consumed by the infectious agent. These results
suggest that predation by D. hesperus foraging among infected whitefly nymphs under greenhouse or natural conditions could be reduced through a combination of
pathogenicity and reduced efficiency of foraging. 相似文献
103.
Jiaqiang Cai D. Jonathan Bennett Zoran Rankovic Maureen Dempster Xavier Fradera Jonathan Gillespie Iain Cumming William Finlay Mark Baugh Sylviane Boucharens John Bruin Kenneth S. Cameron William Hamilton Jennifer Kerr Emma Kinghorn George McGarry John Robinson Paul Scullion Joost C.M. Uitdehaag Mario van Zeeland Eric Nicolai 《Bioorganic & medicinal chemistry letters》2010,20(15):4447-4450
Starting from previously disclosed equally potent cathepsin K and S inhibitor 4-propyl-6-(3-trifluoromethylphenyl)pyrimidine-2-carbonitrile 1, a novel 2-phenyl-9H-purine-6-carbonitrile scaffold was identified to provide potent and selective cathepsin S inhibitors. 相似文献
104.
Jiaqiang Cai Mark Baugh Darcey Black Clive Long D. Jonathan Bennett Maureen Dempster Xavier Fradera Jonathan Gillespie Fiona Andrews Sylviane Boucharens John Bruin Kenneth S. Cameron Iain Cumming William Hamilton Philip S. Jones Allard Kaptein Emma Kinghorn Maurice Maidment Iain Martin Ann Mitchell Tommi Meulemans 《Bioorganic & medicinal chemistry letters》2010,20(15):4350-4354
6-Phenyl-1H-imidazo[4,5-c]pyridine-4-carbonitrile analogues were identified as potent and selective cathepsin S inhibitor against both purified enzyme and in human JY cell based cellular assays. This core has a very stable thio-trapping nitrile war-head in comparison with the well reported pyrimidine-2-carbonitrile cysteine cathepsin inhibitors. Compound 47 is also very potent in in vivo mouse spleenic Lip10 accumulation assays. 相似文献
105.
Craig Jamieson Robert A. Campbell Iain A. Cumming Kevin J. Gillen Jonathan Gillespie Bert Kazemier Michael Kiczun Yvonne Lamont Amanda J. Lyons John K.F. Maclean Frederic Martin Elizabeth M. Moir John A. Morrow John Pantling Zoran Rankovic Lynn Smith 《Bioorganic & medicinal chemistry letters》2010,20(20):6072-6075
Starting from lead compound 1, we demonstrate how X-ray structural data can be used to understand SAR and expediently optimize bioavailability in a novel series of AMPA receptor modulators, furnishing 5 with improved bioavailability and robust in vivo activity. 相似文献
106.
Duccio Rocchini Niko Balkenhol Gregory A. Carter Giles M. Foody Thomas W. Gillespie Kate S. He Salit Kark Noam Levin Kelly Lucas Miska Luoto Harini Nagendra Jens Oldeland Carlo Ricotta Jane Southworth Markus Neteler 《Ecological Informatics》2010,5(5):318-329
Environmental heterogeneity is considered to be one of the main factors associated with biodiversity given that areas with highly heterogeneous environments can host more species due to their higher number of available niches. In this view, spatial variability extracted from remotely sensed images has been used as a proxy of species diversity, as these data provide an inexpensive means of deriving environmental information for large areas in a consistent and regular manner. The aim of this review is to provide an overview of the state of the art in the use of spectral heterogeneity for estimating species diversity. We will examine a number of issues related to this theme, dealing with: i) the main sensors used for biodiversity monitoring, ii) scale matching problems between remotely sensed and field diversity data, iii) spectral heterogeneity measurement techniques, iv) types of species taxonomic diversity measures and how they influence the relationship between spectral and species diversity, v) spectral versus genetic diversity, and vi) modeling procedures for relating spectral and species diversity. Our review suggests that remotely sensed spectral heterogeneity information provides a crucial baseline for rapid estimation or prediction of biodiversity attributes and hotspots in space and time. 相似文献
107.
108.
Viola R Pelloux J van der Ploeg A Gillespie T Marquis N Roberts AG Hancock RD 《Plant, cell & environment》2007,30(8):973-983
To gain greater insight into the mechanism of dormancy release in the potato tuber, an investigation into physiological and biochemical changes in tuber and bud tissues during the transition from bud dormancy (immediately after harvest) to active bud growth was undertaken. Within the tuber, a rapid shift from storage metabolism (starch synthesis) to reserve mobilization within days of detachment from the mother plant suggested transition from sink to source. Over the same period, a shift in the pattern of [U-(14)C]sucrose uptake by tuber discs from diffuse to punctate accumulation was consistent with a transition from phloem unloading to phloem loading within the tuber parenchyma. There were no gross differences in metabolic capacity between resting and actively growing tuber buds as determined by [U-(14)C]glucose labelling. However, marked differences in metabolite pools were observed with large increases in starch and sucrose, and the accumulation of several organic acids in growing buds. Carboxyfluorescein labelling of tubers clearly demonstrated strong symplastic connection in actively growing buds and symplastic isolation in resting buds. It is proposed that potato tubers rapidly undergo metabolic transitions consistent with bud outgrowth; however, growth is initially prevented by substrate limitation mediated via symplastic isolation. 相似文献
109.
Latijnhouwers M Gillespie T Boevink P Kriechbaumer V Hawes C Carvalho CM 《Journal of experimental botany》2007,58(15-16):4373-4386
Golgins are large coiled-coil proteins that play a role in tethering of vesicles to Golgi membranes and in maintaining the overall structure of the Golgi apparatus. Six Arabidopsis proteins with the structural characteristics of golgins were isolated and shown to locate to Golgi stacks when fused to GFP. Two of these golgin candidates (GC1 and GC2) possess C-terminal transmembrane (TM) domains with similarity to the TM domain of human golgin-84. The C-termini of two others (GC3/GDAP1 and GC4) contain conserved GRAB and GA1 domains that are also found in yeast Rud3p and human GMAP210. GC5 shares similarity with yeast Sgm1p and human TMF and GC6 with yeast Uso1p and human p115. When fused to GFP, the C-terminal domains of AtCASP and GC1 to GC6 localized to the Golgi, showing that they contain Golgi localization motifs. The N-termini, on the other hand, label the cytosol or nucleus. Immuno-gold labelling and co-expression with the cis Golgi Q-SNARE Memb11 resulted in a more detailed picture of the sub-Golgi location of some of these putative golgins. Using two independent assays it is further demonstrated that the interaction between GC5, the TMF homologue, and the Rab6 homologues is conserved in plants. 相似文献
110.
Chk1 regulates the density of active replication origins during the vertebrate S phase 总被引:6,自引:0,他引:6
Maya-Mendoza A Petermann E Gillespie DA Caldecott KW Jackson DA 《The EMBO journal》2007,26(11):2719-2731
The checkpoint kinase 1 (Chk1) preserves genome integrity when replication is performed on damaged templates. Recently, Chk1 has also been implicated in regulating different aspects of unperturbed S phase. Using mammalian and avian cells with compromised Chk1 activity, we show that an increase in active replicons compensates for inefficient DNA polymerisation. In the absence of damage, loss of Chk1 activity correlates with the frequent stalling and, possibly, collapse of active forks and activation of adjacent, previously suppressed, origins. In human cells, super-activation of replication origins is restricted to pre-existing replication factories. In avian cells, in contrast, Chk1 deletion also correlates with the super-activation of replication factories and loss of temporal continuity in the replication programme. The same phenotype is induced in wild-type avian cells when Chk1 or ATM/ATR is inhibited. These observations show that Chk1 regulates replication origin activation and contributes to S-phase progression in somatic vertebrate cells. 相似文献