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21.
JEANNE M. ROBERTSON KNUT HOVERSTEN MICHAEL GRÜNDLER THOMAS J. POORTEN DIANA K. HEWS ERICA BREE ROSENBLUM 《Biological journal of the Linnean Society. Linnean Society of London》2011,103(3):657-667
Colonization of novel habitats is often associated with differences in ecological community composition. For small diurnal animals, differences in predator diversity and abundance can lead to behavioural shifts in the novel habitat. The eastern fence lizard Sceloporus undulatus (Bosc and Daudin, 1801) recently colonized the gypsum dunes of White Sands, a predator‐poor community relative to the predator‐rich community of the surrounding Chihuahuan dark‐soil habitat. We used field experiments to assess S. undulatus anti‐predator behaviour in white‐sand versus dark‐soil habitats, and used laboratory assays to determine whether behavioural differences could be mediated by hormonal regulation. Overall, we found that white‐sand lizards were less vigilant but more wary than their dark‐soil counterparts; it took them longer to detect a simulated predator, but once detected they were more likely to retreat from their perches than dark‐soil lizards. At the proximate level, differences in anti‐predator behaviour could not be explained by differences in plasma hormone levels (corticosterone and testosterone); we detected elevated corticosterone for lizards in our stress treatment relative to control treatment, but found no differences between habitats in baseline or acute corticosterone levels. At the evolutionary level, we suggest that differences in anti‐predator behaviour may be explained by differences across habitats in predation environment, habituation, and/or the cost of retreating. Our study implicates changes in predator community composition in mediating ecological divergence in behaviour. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 657–667. 相似文献
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Pehun Pereyra Gerber Lidia M. Duncan Edward JD Greenwood Sara Marelli Adi Naamati Ana Teixeira-Silva Thomas WM Crozier Ildar Gabaev Jun R. Zhan Thomas E. Mulroney Emily C. Horner Rainer Doffinger Anne E. Willis James ED Thaventhiran Anna V. Protasio Nicholas J. Matheson 《PLoS pathogens》2022,18(2)
Efforts to define serological correlates of protection against COVID-19 have been hampered by the lack of a simple, scalable, standardised assay for SARS-CoV-2 infection and antibody neutralisation. Plaque assays remain the gold standard, but are impractical for high-throughput screening. In this study, we show that expression of viral proteases may be used to quantitate infected cells. Our assays exploit the cleavage of specific oligopeptide linkers, leading to the activation of cell-based optical biosensors. First, we characterise these biosensors using recombinant SARS-CoV-2 proteases. Next, we confirm their ability to detect viral protease expression during replication of authentic virus. Finally, we generate reporter cells stably expressing an optimised luciferase-based biosensor, enabling viral infection to be measured within 24 h in a 96- or 384-well plate format, including variants of concern. We have therefore developed a luminescent SARS-CoV-2 reporter cell line, and demonstrated its utility for the relative quantitation of infectious virus and titration of neutralising antibodies. 相似文献
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Joann?Mudge Steven?B?Cannon Peter?Kalo Giles?ED?Oldroyd Bruce?A?Roe Christopher?D?Town Nevin?D?YoungEmail author 《BMC plant biology》2005,5(1):15
Background
Recent genome sequencing enables mega-base scale comparisons between related genomes. Comparisons between animals, plants, fungi, and bacteria demonstrate extensive synteny tempered by rearrangements. Within the legume plant family, glimpses of synteny have also been observed. Characterizing syntenic relationships in legumes is important in transferring knowledge from model legumes to crops that are important sources of protein, fixed nitrogen, and health-promoting compounds. 相似文献26.
ANDRÉ SCHUITEMAN JAAP JAN VERMEULEN ED DE VOGEL ART VOGEL 《Botanical journal of the Linnean Society. Linnean Society of London》2011,167(3):344-350
Bulbophyllum nocturnum , a species of section Epicrianthes from New Britain, is described and illustrated. It is the first known example of an orchid species in which the flowers open after dark and close in the morning. The poorly understood pollination biology of section Epicrianthes, a clade with highly unusual flowers, is discussed. Attention is drawn to the close resemblance between the petal appendages of some species and the fruiting bodies of certain Myxogastria. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 344–350. 相似文献
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We present results from a screen for de novo variable nuclear loci using a genomic library approach in Sceloporus undulatus, the eastern fence lizard. We tested amplification success for 77 primer pairs in S. undulatus, Sceloporus occidentalis and Sceloporus grammicus. Many loci amplified in all three species suggesting that our primers will be useful for developing sequencing or single nucleotide polymorphism (SNP) genotyping markers in other sceloporine lizards. We also sequenced 19 loci, containing 158 variable sites, for 91 S. undulatus individuals. We report high levels of nucleotide variation in this species with an average of 38 SNPs per kilobase. 相似文献
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The physiological capacity for sucrose breakdown in developingjuice sac cells of acid limes was estimated by assaying theactivity of the three enzymes of sucrose catabolism in additionto vacuolar acid hydrolysis. The maximum potential rates ofsucrose breakdown were compared with the observed rates of carbonutilization. Highest potential rates of sucrose breakdown (28.621mmol cm3 per hydrated active space d1) occurredat the initial stages of fruit development where carbon utilizationwas highest. As the fruit developed, the potential rates ofsucrose breakdown and carbon utilization declined to very lowlevels. At 80% of development, vacuolar acid hydrolysis becamethe only physiological mechanism for sucrose breakdown. Therelatively low amounts of sucrose hydrolysed by acid hydrolysisat this time were just sufficient to account for the measuredcarbon demands. The results suggest that carbon supplied bythis distinct sucrose catabolizing system is able to provideadequate levels of carbon skeletons for the observed levelsof respiration and dry weight deposition early in development,but becomes a limiting factor for growth in the later stages. Key words: Vacuolar acid hydrolysis, Citrus aurantifolia 相似文献