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31.
Oreenaiza Nordin Wesley Donald Wong Hong Ming Teoh Guat Ney Khairul Asuad Mohamed Nor Azlina Abdul Halim Peter Winskill Azahari Abdul Hadi Zulkamal Safi'in Muhammad Renaud Lacroix Sarah Scaife Andrew Robert McKemey Camilla Beech Murad Shahnaz Luke Alphey Derric David Nimmo Wasi Ahmed Nazni Han Lim Lee 《PloS one》2013,8(3)
Dengue is the most important mosquito-borne viral disease. No specific treatment or vaccine is currently available; traditional vector control methods can rarely achieve adequate control. Recently, the RIDL (Release of Insect carrying Dominant Lethality) approach has been developed, based on the sterile insect technique, in which genetically engineered ‘sterile’ homozygous RIDL male insects are released to mate wild females; the offspring inherit a copy of the RIDL construct and die. A RIDL strain of the dengue mosquito, Aedes aegypti, OX513A, expresses a fluorescent marker gene for identification (DsRed2) and a protein (tTAV) that causes the offspring to die. We examined whether these proteins could adversely affect predators that may feed on the insect. Aedes aegypti is a peri-domestic mosquito that typically breeds in small, rain-water-filled containers and has no specific predators. Toxorhynchites larvae feed on small aquatic organisms and are easily reared in the laboratory where they can be fed exclusively on mosquito larvae. To evaluate the effect of a predator feeding on a diet of RIDL insects, OX513A Ae. aegypti larvae were fed to two different species of Toxorhynchites (Tx. splendens and Tx. amboinensis) and effects on life table parameters of all life stages were compared to being fed on wild type larvae. No significant negative effect was observed on any life table parameter studied; this outcome and the benign nature of the expressed proteins (tTAV and DsRed2) indicate that Ae. aegypti OX513A RIDL strain is unlikely to have any adverse effects on predators in the environment. 相似文献
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Intermediate habitat associations by hybrids may facilitate genetic introgression in a songbird 下载免费PDF全文
Eric M. Wood Sara E. Barker Swarthout Wesley M. Hochachka Jeffery L. Larkin Ronald W. Rohrbaugh Kenneth V. Rosenberg Amanda D. Rodewald 《Journal of avian biology》2016,47(4):508-520
Hybridization or the interbreeding of genetically discrete populations or species can occur where ranges of genetically distinct units overlap. Golden‐winged warblers Vermivora chrysoptera, a species that has been in steady decline for decades, highlight the potential population‐level consequences of hybridization. A major factor implicated in their decline is hybridization with their sister species, the blue‐winged warbler Vermivora cyanoptera, which has likely been exacerbated by historic and current land‐use practices. We examined habitat associations of golden‐winged and blue‐winged warblers, phenotypic hybrids, and cryptic hybrids (i.e. mismatch between plumage phenotype and genotype as identified by mitochondrial DNA) in an area of relatively recent range overlap and hybridization in northern New York, USA. To explore the robustness of these results, we then compared the patterns from New York with habitat associations from the central Pennsylvanian Appalachian Mountains where blue‐winged warblers either do not occur or are in very low abundance, yet cryptic golden‐winged warbler hybrids are present. From 2008 to 2011, we captured 122 birds in New York and 28 in Pennsylvania and collected blood samples, which we used to determine maternal ancestry. For each bird captured, we measured territory‐level (50‐m radius circles) habitat, and later used remote‐sensing data to quantify habitat on the territories and in surrounding areas (100‐, 250‐, and 500‐m radius circles). In New York, golden‐winged warblers occupied structurally heterogeneous territories surrounded by homogeneously structured, contiguous deciduous forest, far from urban areas. Blue‐winged warblers showed opposite associations, and hybrids’ habitat associations were typically intermediate. In Pennsylvania, the habitat associations of golden‐winged warblers and their cryptic hybrids were remarkably similar to those in New York. These findings suggest that patterns of habitat occupancy by hybrids may promote contact with golden‐winged warblers and thus likely facilitate genetic introgression, even in areas where the parental species are not sympatric. 相似文献
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Vilizzi Lorenzo Copp Gordon H. Adamovich Boris Almeida David Chan Joleen Davison Phil I. Dembski Samuel Ekmekçi F. Güler Ferincz Árpád Forneck Sandra C. Hill Jeffrey E. Kim Jeong-Eun Koutsikos Nicholas Leuven Rob S. E. W. Luna Sergio A. Magalhães Filomena Marr Sean M. Mendoza Roberto Mourão Carlos F. Neal J. Wesley Onikura Norio Perdikaris Costas Piria Marina Poulet Nicolas Puntila Riikka Range Inês L. Simonović Predrag Ribeiro Filipe Tarkan Ali Serhan Troca Débora F. A. Vardakas Leonidas Verreycken Hugo Vintsek Lizaveta Weyl Olaf L. F. Yeo Darren C. J. Zeng Yiwen 《Reviews in Fish Biology and Fisheries》2019,29(3):529-568
Reviews in Fish Biology and Fisheries - The freshwater Fish Invasiveness Screening Kit (FISK) has been applied in 35 risk assessment areas in 45 countries across the six inhabited continents (11... 相似文献
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Intertidal zone mussels can face threats from a variety of predatory species during high and low tides, and they must balance the threat of predation against other needs such as feeding and aerobic respiration. Black oystercatchers (Haematopus bachmani) on the Pacific coast of North America can depend on the mussel Mytilus californianus for a substantial portion of their diet. Observations suggest that oystercatchers tend to focus on mussels beginning to gape their valves during rising tides, following periods of aerial emersion. We present detailed, autonomous field measurements of the dynamics of three such predation events in the rocky intertidal zone. We measured accelerations of up to 4 g imposed on mussels, with handling times of 115–290 s required to open the shell and remove the majority of tissue. In each case a single oystercatcher attacked a mussel that had gaped the shell valves slightly wider than its neighbors as the rising tide began to splash the mussel bed, but no other obvious characteristic of the mussels, such as body temperature or orientation, could be linked to the oystercatcher's individual prey choice. 相似文献
37.
Valérian Meline Wesley Delage Chrystelle Brin Camille Li-Marchetti Daniel Sochard Matthieu Arlat Céline Rousseau Armelle Darrasse Martial Briand Guillaume Lebreton Perrine Portier Marion Fischer-Le Saux Karine Durand Marie-Agnès Jacques Etienne Belin Tristan Boureau 《Molecular Plant Pathology》2019,20(1):33-50
Cases of emergence of novel plant-pathogenic strains are regularly reported that reduce the yields of crops and trees. However, the molecular mechanisms underlying such emergence are still poorly understood. The acquisition by environmental non-pathogenic strains of novel virulence genes by horizontal gene transfer has been suggested as a driver for the emergence of novel pathogenic strains. In this study, we tested such an hypothesis by transferring a plasmid encoding the type 3 secretion system (T3SS) and four associated type 3 secreted proteins (T3SPs) to the non-pathogenic strains of Xanthomonas CFBP 7698 and CFBP 7700, which lack genes encoding T3SS and any previously known T3SPs. The resulting strains were phenotyped on Nicotiana benthamiana using chlorophyll fluorescence imaging and image analysis. Wild-type, non-pathogenic strains induced a hypersensitive response (HR)-like necrosis, whereas strains complemented with T3SS and T3SPs suppressed this response. Such suppression depends on a functional T3SS. Amongst the T3SPs encoded on the plasmid, Hpa2, Hpa1 and, to a lesser extent, XopF1 collectively participate in suppression. Monitoring of the population sizes in planta showed that the sole acquisition of a functional T3SS by non-pathogenic strains impairs growth inside leaf tissues. These results provide functional evidence that the acquisition via horizontal gene transfer of a T3SS and four T3SPs by environmental non-pathogenic strains is not sufficient to make strains pathogenic. In the absence of a canonical effector, the sole acquisition of a T3SS seems to be counter-selective, and further acquisition of type 3 effectors is probably needed to allow the emergence of novel pathogenic strains. 相似文献
38.
Kobayashi T Antar AA Boehme KW Danthi P Eby EA Guglielmi KM Holm GH Johnson EM Maginnis MS Naik S Skelton WB Wetzel JD Wilson GJ Chappell JD Dermody TS 《Cell host & microbe》2007,1(2):147-157
Mammalian orthoreoviruses (reoviruses) are highly tractable experimental models for studies of double-stranded (ds) RNA virus replication and pathogenesis. Reoviruses infect respiratory and intestinal epithelium and disseminate systemically in newborn animals. Until now, a strategy to rescue infectious virus from cloned cDNA has not been available for any member of the Reoviridae family of dsRNA viruses. We report the generation of viable reovirus following plasmid transfection of murine L929 (L) cells using a strategy free of helper virus and independent of selection. We used the reovirus reverse genetics system to introduce mutations into viral capsid proteins sigma1 and sigma3 and to rescue a virus that expresses a green fluorescent protein (GFP) transgene, thus demonstrating the tractability of this technology. The plasmid-based reverse genetics approach described here can be exploited for studies of reovirus replication and pathogenesis and used to develop reovirus as a vaccine vector. 相似文献
39.
POPULATION STRUCTURE OF THE BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATUS) AS DETERMINED BY RESTRICTION ENDONUCLEASE ANALYSIS OF MITOCHONDRIAL DNA 总被引:1,自引:0,他引:1
Abstract: Restriction fragment length polymorphisms of mitochondrial DNA (mtDNA) were used to test for population subdivision in the bottlenose dolphin (Tursiops truncatus). Atlantic and Pacific dolphin mtDNA samples exhibited distinctly different haplotypes (approximately 2.4% sequence divergence), indicating a lack of gene exchange. Within the Atlantic Ocean, mtDNA samples from the Gulf of Mexico and the Atlantic Coast were also found to be distinct, with a sequence divergence of approximately 0.6%. The Atlantic Coast–Gulf of Mexico dichotomy is consistent with patterns of genetic variation from other marine and coastal organisms from this region, and supports the hypothesized role of bio-geographic events in promoting the divergence of these and other forms. Regional differentiation was identified along the Atlantic Coast, whereas low sequence divergences among haplotypes and consistent haplotype frequencies across populations suggested considerable gene exchange among Gulf of Mexico populations. A highly divergent haplotype found in two individuals from two localities in the Gulf of Mexico is best explained by dispersal from either a distinct offshore Gulf stock or an unsampled Atlantic Coast stock. Additional samples are required to test for the existence of a distinct offshore race and, if it exists, to identify its distribution and contribution to population structure. 相似文献
40.
The purpose of this article is to describe the treatment of a 45-year-old male with a hyperfunctional voice disorder by a biofeedback therapist and a speech-language pathologist. The interdisciplinary approach to the treatment of this voice disorder involved the combined use of traditional voice therapy techniques and EMG biofeedback procedures together with cognitive behavioral therapy. Voice therapy was facilitated through the use of a computer-based, speech-monitoring system. The remediation of this voice disorder was attributed to the collaborative efforts of two professionals representing diverse professional training and treatment protocols. The results showed reductions in muscle activity in the infrahyoid and laryngeal areas as well as improved use of proper breathing and voicing onset behaviors. Follow-up at 10 and 15 months posttreatment intervals indicated that the client had retained all target voice skills and the tension reduction/biofeedback skills. Results suggest that interdisciplinary, collaborative efforts using biofeedback and voice therapy can prove beneficial in the treatment of hyperfunctional voice disorders.Note: Neither author has been compensated in any way for the use of the CAFET System nor does either have any financial interest in the company. 相似文献