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991.
Recognition and Response to Native and Novel Predators in the Largespring mosquitofish,Gambusia geiseri 下载免费PDF全文
Chelsea A. Blake Laura Alberici da Barbiano Jessica E. Guenther Caitlin R. Gabor 《Ethology : formerly Zeitschrift fur Tierpsychologie》2015,121(3):227-235
The introduction of predator species into new habitats is an increasingly common consequence of human activities, and the persistence of native prey species depends upon their response to these novel predators. In this study, we examined whether the Largespring mosquitofish, Gambusia geiseri exhibited antipredator behavior and/or an elevation of circulating stress hormones (cortisol) to visual and chemical cues from a native predator, a novel predator, or a non‐predatory control fish. Prey showed the most pronounced antipredator response to the native predator treatment, by moving away from the stimulus, while the prey showed no significant changes in their vertical or horizontal position in response to the novel or non‐predator treatments. We also found no significant difference in water‐borne cortisol release rates following any of the treatments. Our results suggest the prey did not recognize and exhibit antipredator behavior to the novel predator, and we infer that this predator species could be detrimental if it expands into the range of this prey species. Further, our study demonstrates prey may not respond to an invasive predator that is phylogenetically, behaviorally, and morphologically dissimilar from the prey species' native predators. 相似文献
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993.
The Increase in Maternal Expression of axin1 and axin2 Contribute to the Zebrafish Mutant Ichabod Ventralized Phenotype 下载免费PDF全文
Fabio Valenti Jessica Ibetti Yuko Komiya Melissa Baxter Anna Maria Lucchese Lauren Derstine Claudia Covaciu Valeria Rizzo Renza Vento Giuseppe Russo Marcella Macaluso Franco Cotelli Daniele Castiglia Cara J. Gottardi Raymond Habas Antonio Giordano Gianfranco Bellipanni 《Journal of cellular biochemistry》2015,116(3):418-430
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995.
Cross‐species chimeras reveal BamA POTRA and β‐barrel domains must be fine‐tuned for efficient OMP insertion 下载免费PDF全文
Douglas F. Browning Vassiliy N. Bavro Jessica L. Mason Yanina R. Sevastsyanovich Amanda E. Rossiter Mark Jeeves Timothy J. Wells Timothy J. Knowles Adam F. Cunningham James W. Donald Tracy Palmer Michael Overduin Ian R. Henderson 《Molecular microbiology》2015,97(4):646-659
BAM is a conserved molecular machine, the central component of which is BamA. Orthologues of BamA are found in all Gram‐negative bacteria, chloroplasts and mitochondria where it is required for the folding and insertion of β‐barrel containing integral outer membrane proteins (OMPs) into the outer membrane. BamA binds unfolded β‐barrel precursors via the five polypeptide transport‐associated (POTRA) domains at its N‐terminus. The C‐terminus of BamA folds into a β‐barrel domain, which tethers BamA to the outer membrane and is involved in OMP insertion. BamA orthologues are found in all Gram‐negative bacteria and appear to function in a species‐specific manner. Here we investigate the nature of this species‐specificity by examining whether chimeric Escherichia coli BamA fusion proteins, carrying either the β‐barrel or POTRA domains from various BamA orthologues, can functionally replace E. coli BamA. We demonstrate that the β‐barrel domains of many BamA orthologues are functionally interchangeable. We show that defects in the orthologous POTRA domains can be rescued by compensatory mutations within the β‐barrel. These data reveal that the POTRA and barrel domains must be precisely aligned to ensure efficient OMP insertion. 相似文献
996.
Jessica Lawrence David Cameron David Argyle 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1673)
Despite advances in chemotherapy, radiotherapy and targeted drug development, cancer remains a disease of high morbidity and mortality. The treatment of human cancer patients with chemotherapy has become commonplace and accepted over the past 100 years. In recent years, and with a similar incidence of cancer to people, the use of cancer chemotherapy drugs in veterinary patients such as the dog has also become accepted clinical practice. The poor predictability of tumour responses to cancer chemotherapy drugs in rodent models means that the standard drug development pathway is costly, both in terms of money and time, leading to many drugs failing in Phase I and II clinical trials. This has led to the suggestion that naturally occurring cancers in pet dogs may offer an alternative model system to inform rational drug development in human oncology. In this review, we will explore the species variation in tumour responses to conventional chemotherapy and highlight our understanding of the differences in pharmacodynamics, pharmacokinetics and pharmacogenomics between humans and dogs. Finally, we explore the potential hurdles that need to be overcome to gain the greatest value from comparative oncology studies. 相似文献
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998.
Jessica A. Wisniewski Wee L. Teng Trudi L. Bannam Julian I. Rood 《Journal of bacteriology》2015,197(4):774-781
The anaerobic pathogen Clostridium perfringens encodes either toxin genes or antibiotic resistance determinants on a unique family of conjugative plasmids that have a novel conjugation region, the tcp locus. Studies of the paradigm conjugative plasmid from C. perfringens, the 47-kb tetracycline resistance plasmid pCW3, have identified several tcp-encoded proteins that are involved in conjugative transfer and form part of the transfer apparatus. In this study, the role of the conserved hypothetical proteins TcpD, TcpE, and TcpJ was examined. Mutation and complementation analyses showed that TcpD and TcpE were essential for the conjugative transfer of pCW3, whereas TcpJ was not required. To analyze the TcpD and TcpE proteins in C. perfringens, functional hemagglutinin (HA)-tagged derivatives were constructed. Western blots showed that TcpD and TcpE localized to the cell envelope fraction independently of the presence of other pCW3-encoded proteins. Finally, examination of the subcellular localization of TcpD and TcpE by immunofluorescence showed that these proteins were concentrated at both poles of C. perfringens donor cells, where they are postulated to form essential components of the multiprotein complex that comprises the transfer apparatus. 相似文献
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1000.
André E. Minoche Juliane C. Dohm Jessica Schneider Daniela Holtgr?we Prisca Vieh?ver Magda Montfort Thomas Rosleff S?rensen Bernd Weisshaar Heinz Himmelbauer 《Genome biology》2015,16(1)
We develop a method to predict and validate gene models using PacBio single-molecule, real-time (SMRT) cDNA reads. Ninety-eight percent of full-insert SMRT reads span complete open reading frames. Gene model validation using SMRT reads is developed as automated process. Optimized training and prediction settings and mRNA-seq noise reduction of assisting Illumina reads results in increased gene prediction sensitivity and precision. Additionally, we present an improved gene set for sugar beet (Beta vulgaris) and the first genome-wide gene set for spinach (Spinacia oleracea). The workflow and guidelines are a valuable resource to obtain comprehensive gene sets for newly sequenced genomes of non-model eukaryotes.