The Experts below are selected from a list of 1038 Experts worldwide ranked by ideXlab platform
Hong M. - One of the best experts on this subject based on the ideXlab platform.
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Early-life intestinal microbiome in Trachemys scripta elegans analyzed using 16S rRNA sequencing
2020Co-Authors: Peng Q., Chen Y., Ding L., Zhao Z., Yan P., Storey K. B.), Shi H., Hong M.Abstract:During the early-life period, the hatchlings of Red-Eared Slider turtles (Trachemys scripta elegans) rely on their own post-hatching internal yolk for several days before beginning to feed. The gut microbiome is critical for the adaptation of organisms to new environ- ments, but, to date, how the microbiome taxa are assembled during early life of the turtle is unknown. In this study, the intestinal microbiome of Red-Eared Slider hatchlings (fed on commercial particle food
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Early-life intestinal microbiome in Trachemys scripta elegans analyzed using 16S rRNA sequencing
'PeerJ', 2020Co-Authors: Peng Q., Chen Y., Ding L., Zhao Z., Yan P., Storey K. B.), Shi H., Hong M.Abstract:During the early-life period, the hatchlings of Red-Eared Slider turtles (Trachemys scripta elegans) rely on their own post-hatching internal yolk for several days before beginning to feed. The gut microbiome is critical
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Adenosine Monophosphate-Activated Protein Kinase Signaling Regulates Lipid Metabolism in Response to Salinity Stress in the Red-Eared Slider Turtle Trachemys scripta elegans
'Frontiers Media SA', 2019Co-Authors: Hong M., Storey K. B.), Shi H., Li N., Li J., Li W., Liang L., Li Q., Wang R., Ding L.Abstract:Aquatic animals have developed various mechanisms to live in either hyperionic or hypoionic environments, and, as such, not many species are capable of surviving in both. The Red-Eared Slider turtle, Trachemys scripta elegans, a well-known freshwater species, has recently been found to invade and inhabit brackish water. Herein, we focus on some of the metabolic adaptations that are required to survive and cope with salinity stress. The regulation of the adenosine monophosphate (AMP)-activated protein kinase (AMPK), a main cellular “energy sensor,” and its influence on lipid metabolism were evaluated with a comparison of three groups of turtles: controls in freshwater, and turtles held in water of either 5 salinity (S5) or 15 salinity (S15) with sampling at 6, 24, and 48 h and 30 days of exposure. When subjected to elevated salinities of 5 or 15, AMPK mRNA levels and AMPK enzyme activity increased strongly. In addition, the high expression of the peroxisome proliferator activated receptor-α (PPARα) transcription factor that, in turn, facilitated upregulation of target genes including carnitine palmitoyltransferase (CPT) and acyl-CoA oxidase (ACO). Furthermore, the expression of transcription factors involved in lipid synthesis such as the carbohydrate-responsive element-binding protein (ChREBP) and sterol regulatory element-binding protein 1c (SREBP-1c) was inhibited, and two of their target genes, acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), were significantly decreased. Moreover, exposure to saline environments also increased plasma triglyceride (TG) content. Interestingly, the content of low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) in plasma was markedly higher than the control in the S15 group after 30 days, which indicated that lipid metabolism was disrupted by chronic exposure to high salinity. These findings demonstrate that activation of AMPK might regulate lipid metabolism in r
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Comparative analysis of the liver transcriptome in the Red-Eared Slider Trachemys scripta elegans under chronic salinity stress
'PeerJ', 2019Co-Authors: Hong M., Storey K. B.), Shi H., Li N., Li W., Jiang A., Ding L.Abstract:The Red-Eared Slider (Trachemys scripta elegans), identified as one of the 100 most invasive species in the world, is a freshwater turtle originally from the eastern United States and northeastern Mexico. Field investigations have shown that T. s. elegans can survive and lay eggs in saline habitats. In order to understand the molecular mechanisms of salinity adaptation, high-throughput RNA-Seq was utilized to identify the changes in gene expression profiles in the liver of T. s. elegans in response to elevated salinity. We exposed individuals to 0, 5, or 15 psu (practical salinity units) for 30 days. A total of 157.21 million reads were obtained and assembled into 205138 unigenes with an average length of 620 bp and N50 of 964 bp. Of these, 1019 DEGs (differentially expressed genes) were found in the comparison of 0 vs. 5 psu, 1194 DEGs in 0 vs. 15 psu and 1180 DEGs in 5 vs. 15 psu, which are mainly related to macromolecule metabolic process, ion transport, oxidoreductase activity and generation of precursor metabolites and energy by GO (Gene Ontology) enrichment analyses. T. s. elegans can adapt itself into salinity by balancing the entry of sodium and chloride ions via the up-regulation expression genes of ion transport (potassium voltage-gated channel subfamily H member 5, KCNH5; erine/threonine-protein kinase 32, STK32; salt-inducible kinase 1, SIK1; adiponectin, ACDC), and by accumulating plasma urea and free amino acid via the up-regulation expression genes of amino acid metabolism (ornithine decarboxylase antizyme 3, OAZ3; glutamine synthetase, GLUL; asparaginase-like protein 1b, ASRGL; L-amino-acid oxidase-like, LAAO; sodium-dependent neutral amino acid transporter B, SLC6A15s; amino acid permease, SLC7A9) in response to osmotic regulation. An investment of energy to maintain their homeostatic balance is required to salinity adaptation, therefore, the genes related to energy production and conversion (F-ATPase protein 6, ATP6; cytochrome c oxidase subunit I, COX1; cytochrome c oxidase subunit III, COX3; cytochrome b, CYTb; cytochrome P450 17A1, CYP17A1) were up-regulated with the increase of gene expression associated with lipid metabolism (apolipoprotein E precursor, APoE; coenzyme Q-binding protein, CoQ10; high-density lipoprotein particle, SAA) and carbohydrate metabolism (HK, MIP). These findings improve our understanding of the underlying molecular mechanisms involved in salinity adaptationand provide general guidance to illuminate the invasion potential of T. s. elegans into saline environments
Haitao Shi - One of the best experts on this subject based on the ideXlab platform.
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modulation of the intestinal barrier adaptive functions in red eared Slider trachemys scripta elegans invading brackish waters
Science of The Total Environment, 2021Co-Authors: Li Ding, Haitao Shi, Lingyue Liang, Zubin Huang, Jiliang Zhang, Kenneth B Storey, Meiling HongAbstract:Globally, the increase in sea levels is leading to salinization of freshwater, which might influence the freshwater organisms such as Red-Eared Slider, Trachemys scripta elegans. The turtle can invade brackish water environments, in which it must deal with elevated salinity in the gastrointestinal tract that could impact the intestinal function. The intestinal barrier provides a front-line of organismal defense against the chemical and biological environmental insults. In this study, the adaptive functions of the intestinal barrier including intestinal histomorphology, genes involved in intestinal barrier functions, and the intestinal micro-ecosystem were analyzed in the turtles exposed to freshwater (S0), 5‰ salinity (S5) and 15‰ salinity (S15) water for 30 days. The results showed that the intestine of T. s. elegans maintained normal histomorphological structure in the S5 group, whereas the villus height, crypt depth and the number of goblet cells in the S15 group were lower than that in the S5 and S0 groups. In addition, the relative expression levels of epithelial tight junction-related genes and intestinal immune-related genes in the gut were significantly upregulated in the S15 group, compared to the freshwater group. Mucin-2 gene expression was downregulated, but mucin-1 transcript levels were upregulated in salinity-treated groups. Furthermore, the abundances of phylum Proteobacteria, and genera Morganella and Aeromonas in the intestine were particularly enhanced in the S15 group than the S0 and S5 groups. Taken together, these results indicate that the intestinal barrier plays a protective role in T. s. elegans adaptation to brackish water environments. Our results provide a perspective on the evolution of salinity tolerance and help to evaluate the potential danger of the turtle to other species, and understand the challenges that other species must meet with rising sea levels.
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developmental plasticity of hearing sensitivity in red eared Slider trachemys scripta elegans
bioRxiv, 2019Co-Authors: Jichao Wang, Tongliang Wang, Haitao Shi, Jianguo Cui, Bo ChenAbstract:Abstract Developmental plasticity of hearing sensitivity (DPHS) has been verified in some groups of vertebrates. Turtles face a trade-off between terrestrial and aquatic hearing in different acoustic environments throughout ontogeny. However, how chelonian hearing sensitivity changes throughout ontogeny is still unclear. To verify DPHS in turtles, auditory brainstem responses (ABR) were compared using hearing thresholds and latencies in female Red-Eared Slider (Trachemys scripta elegans) aged 1 week, 1 month, 1 year, and 5 years, and the results showed hearing sensitivity bandwidths of approximately 200–1100, 200–1100, 200–1300, and 200–1400 Hz, respectively. The lowest threshold sensitivity was approximately 600□Hz. Below 600 Hz, ABR threshold decreased rapidly with increasing age (1 week to 1 year), with significant differences between age groups, but no significant difference between the 1- and 5-year age groups (stimulus frequency, 200–600 Hz). Above 600 Hz, ABR threshold was the lowest in the 5-year age group. These findings show that aging was accompanied by hearing sensitivity changes, suggesting rapid, frequency-segmented development during ontogeny. This variability in hearing sensitivity differs from that reported in other vertebrates, and allows adaptation to acoustically distinct environments throughout ontogeny. Our findings further elucidate the developmental patterns of the vertebrate auditory system.
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regulation of p53 in the red eared Slider trachemys scripta elegans in response to salinity stress
Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2019Co-Authors: Lingyue Liang, Haitao Shi, Meiling Hong, Peng Ren, Li DingAbstract:The freshwater Red-Eared Slider (Trachemys scripta elegans) is found not only in freshwater but also in coastal saline habitats. Hyperosmotic salinity can induce cell damage. p53, regarded as the guardian of the genome, is very important and versatile in response to the change of environment. In this study, the role of p53 in T. s. elegans under environmental salinity change will be explored. The results indicated that amino acid sequence of p53 showed high similarity to p53 of other species. In addition, the expression of p53 showed differences in various tissues under normal condition. Under salinity stress, the mRNA levels of p53 in the liver increased significantly at 48 h with 15‰ group (15 practical salinity units-exposed group). In the heart, p53 mRNA levels increased at 6 h in 5‰ (5 practical salinity units) and 15‰ groups. Furthermore, the changes of p21 mRNA expression levels in liver and heart were similar to p53, while cyclin D1, cyclin-dependent kinase4 (CDK4) and cyclin-dependent kinase6 (CDK6) showed opposite changes to p53. Moreover, Bax and caspase 3 mRNA expression levels were similar to p53, respectively, while Bcl-2 showed opposite changes. The positive cells of apoptosis were found in the liver of 15‰ at 48 h and 30 d of chronic stress. Taken together, these results indicated that the T. s. elegans may protect itself by regulating cell cycle progression and apoptosis of damaged cells under salinity stress, which played an important role for T. s. elegans in salinity adaptation.
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antioxidant responses to salinity stress in an invasive species the red eared Slider trachemys scripta elegans and involvement of a tor nrf2 signaling pathway
Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2019Co-Authors: Li Ding, Haitao Shi, Lingyue Liang, Kenneth B Storey, Xinying Zhang, Huilin Jin, Meiling HongAbstract:Abstract The Red-Eared Slider (Trachemys scripta elegans), a freshwater turtle, is an invasive species in many parts of the world where it survives in both freshwater and coastal saline habitats. High salinity can induce reactive oxygen species (ROS) production and lead to oxidative damage. In this study, we investigate the antioxidant defense mechanisms of T. s. elegans in response to salinity stress. The results showed that the mRNA expression levels of superoxide dismutase (SODs), catalase (CAT) and glutathione peroxidase (GSH-PXs) were significantly increased in both 5 psu and 15 psu groups at the early stages of salinity exposure (generally 6–48 h), but typically returned to control levels after the longest 30 d exposure. In addition, hepatic and cardiac mRNA levels of the NF-E2-related factor 2 (Nrf2), showed a similar upregulation as an early response to stress, but decreased at 30 d in the 5 psu and 15 psu groups. The mRNA levels of the negative regulator of Nrf2, kelch-like ECH associating protein 1 (Keap1), exhibited the opposite pattern. Moreover, mRNA expression levels of target of rapamycin (TOR) and ribosomal protein S6 kinase 1 (S6K1) in liver and heart showed roughly similar patterns to those for Nrf2. Furthermore, the content of malondialdehyde (MDA) was significantly increased in liver, especially in the 15 psu group by ~2.5-fold. Taken together, these results indicate that T. s. elegans may activate the TOR-Nrf2 pathway to modulate antioxidant genes transcription in order to promote enhanced antioxidant defense in response to salinity stress.
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adenosine monophosphate activated protein kinase signaling regulates lipid metabolism in response to salinity stress in the red eared Slider turtle trachemys scripta elegans
Frontiers in Physiology, 2019Co-Authors: Meiling Hong, Haitao Shi, Lingyue Liang, Kenneth B Storey, Runqi Wang, Li DingAbstract:Aquatic animals have developed various mechanisms to live in either hyperionic or hypoionic environments and, as such, not many species are capable of surviving in both. The Red-Eared Slider turtle, Trachemys scripta elegans, a well-known freshwater species, has recently been found to invade and inhabit brackish water. Herein, we focus on some of the metabolic adaptations that are required to survive and cope with salinity stress. The regulation of the AMP-activated protein kinase (AMPK), a main cellular “energy sensor” and its influence on lipid metabolism were evaluated with a comparison of three groups of turtles: controls in freshwater, and turtles held in water of either 5‰ salinity (S5) or and 15‰ salinity (S15) with sampling at 6 h, 24 h, 48 h and 30 d of exposure. When subjected to elevated salinities of 5‰ or 15‰, AMPK mRNA levels and AMPK enzyme activity increased strongly. Salinity-activated AMPK promoted the expression of the peroxisome proliferator activated receptor-α (PPARα) transcription factor that, in turn, facilitated upregulation of target genes including carnitine palmitoyltransferase (CPT) and acyl-CoA oxidase (ACO). Elevated AMPK also led to inhibition of transcription factors involved in lipid synthesis, such as the carbohydrate-responsive element-binding protein (ChREBP) and sterol regulatory element binding protein 1c (SREBP-1c), as well as significantly decreasing two of their target genes, acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS). Exposure to saline environments also increased plasma triglyceride (TG) content. Interestingly, the content of low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) in serum were markedly higher than control levels in the S15 group after 30 days, which indicated that lipid metabolism was disrupted by chronic exposure to high salinity. These findings demonstrate that activation of AMPK regulates lipid metabolism in response to salinity stress through the inhibition of lipid synthesis and promotion of lipid oxidation in the liver of T. s. elegans. This may be an important component of the observed salinity tolerance of these turtles that allow for invasion of brackish waters.
David Crews - One of the best experts on this subject based on the ideXlab platform.
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gonadal expression of sf1 and aromatase during sex determination in the red eared Slider turtle trachemys scripta a reptile with temperature dependent sex determination
Differentiation, 2007Co-Authors: Mary E. Ramsey, Christina M. Shoemaker, David CrewsAbstract:Many egg-laying reptiles have temperature-dependent sex determination (TSD), where the offspring sex is determined by incubation temperature during a temperature-sensitive period (TSP) in the middle third of development. The underlying mechanism transducing a temperature cue into an ovary or testis is unknown, but it is known that steroid hormones play an important role. During the TSP, exogenous application of estrogen can override a temperature cue and produce females, while blocking the activity of aromatase (Cyp19a1), the enzyme that converts testosterone to estradiol, produces males from a female-biased temperature. The production of estrogen is a key step in ovarian differentiation for many vertebrates, including TSD reptiles, and temperature-based differences in aromatase expression during the TSP may be a critical step in ovarian determination. Steroidogenic factor-1 (Sf1) is a key gene in vertebrate sex determination and regulates many steroidogenic enzymes, including aromatase. We find that Sf1 and aromatase are differentially expressed during sex determination in the Red-Eared Slider turtle, Trachemys scripta elegans. Sf1 is expressed at higher levels during testis development while aromatase expression increases during ovary determination. We also assayed Sf1 and aromatase response to sex-reversing treatments via temperature or the modulation of estrogen availability. Sf1 expression was redirected to low-level female-specific patterns with feminizing temperature shift or exogenous estradiol application and redirected to more intense male-specific patterns with male-producing temperature shift or inhibition of aromatase activity. Conversely, aromatase expression was redirected to more intense female-specific patterns with female-producing treatment and redirected toward diffuse low-level male-specific patterns with masculinizing sex reversal. Our data do not lend support to a role for Sf1 in the regulation of aromatase expression during Slider turtle sex determination, but do support a critical role for estrogen in ovarian development.
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adrenal kidney gonad complex measurements may not predict gonad specific changes in gene expression patterns during temperature dependent sex determination in the red eared Slider turtle trachemys scripta elegans
Journal of Experimental Zoology, 2007Co-Authors: Mary E. Ramsey, David CrewsAbstract:Many turtles, including the Red-Eared Slider turtle (Trachemys scripta elegans) have temperature-dependent sex determination in which gonadal sex is determined by temperature during the middle third of incubation. The gonad develops as part of a heterogenous tissue complex that comprises the developing adrenal, kidney, and gonad (AKG complex). Owing to the difficulty in excising the gonad from the adjacent tissues, the AKG complex is often used as tissue source in assays examining gene expression in the developing gonad. However, the gonad is a relatively small component of the AKG, and gene expression in the adrenal-kidney (AK) compartment may interfere with the detection of gonad-specific changes in gene expression, particularly during early key phases of gonadal development and sex determina- tion. In this study, we examine transcript levels as measured by quantitative real-time polymerase chain reaction for five genes important in Slider turtle sex determination and differentiation (AR, ERa ,E Rb, aromatase, and Sf1) in AKG, AK, and isolated gonad tissues. In all cases, gonad-specific gene expression patterns were attenuated in AKG versus gonad tissue. All five genes were expressed in the AK in addition to the gonad at all stages/temperatures. Inclusion of the AK compartment masked important changes in gonadal gene expression. In addition, AK and gonad expression patterns are not additive, and gonadal gene expression cannot be predicted from intact AKG
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Steroid signaling system responds differently to temperature and hormone manipulation in the Red-Eared Slider turtle (Trachemys scripta elegans), a reptile with temperature-dependent sex determination.
Sexual development : genetics molecular biology evolution endocrinology embryology and pathology of sex determination and differentiation, 2007Co-Authors: Mary E. Ramsey, David CrewsAbstract:Many reptiles, including the Red-Eared Slider turtle ( Trachemys scripta elegans ), exhibit temperature-dependent sex determination (TSD). Temperature determines gonadal sex during th
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embryonic treatment with xenobiotics disrupts steroid hormone profiles in hatchling red eared Slider turtles trachemys scripta elegans
Environmental Health Perspectives, 2000Co-Authors: Emily Willingham, Turk Rhen, Jon T Sakata, David CrewsAbstract:Many compounds in the environment capable of acting as endocrine disruptors have been assayed for their developmental effects on morphogenesis; however, few studies have addressed how such xenobiotics affect physiology. In the current study we examine the effects of three endocrine-disrupting compounds, chlordane, trans-nonachlor, and the polychlorinated biphenyl (PCB) mixture Aroclor 1242, on the steroid hormone concentrations of Red-Eared Slider turtle (Trachemys scripta elegans) hatchlings treated in ovo. Basal steroid concentrations and steroid concentrations in response to follicle-stimulating hormone were examined in both male and female turtles treated with each of the three compounds. Treated male turtles exposed to Aroclor 1242 or chlordane exhibited significantly lower testosterone concentrations than controls, whereas chlordane-treated females had significantly lower progesterone, testosterone, and 5[alpha]-dihydrotestosterone concentrations relative to controls. The effects of these endocrine disruptors extend beyond embryonic development, altering sex-steroid physiology in exposed animals.
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role of reductase and aromatase in sex determination in the red eared Slider trachemys scripta a turtle with temperature dependent sex determination
Journal of Endocrinology, 1994Co-Authors: David Crews, Judith M BergeronAbstract:In many turtles the temperature during the middle of incubation determines the gonadal sex of the hatchling. In the Red-Eared Slider turtle (Trachemys scripta), an incubation temperature of 26 degrees C results in all male offspring, whereas an incubation temperature of 31 degrees C results in all female offspring; at temperatures intermediate to these (e.g. 29, 29.2, 29.4 degrees C) a mixed sex ratio is obtained. Administration of exogenous oestrogens will overcome the effects of an all-male producing incubation temperature to cause female sex determination, whereas administration of exogenous dihydrotestosterone (DHT) or testosterone to eggs incubating at an all-female temperature will have no discernible effect. Administration of DHT will cause male sex determination only if administered at intermediate incubation temperatures whereas administration of testosterone to eggs incubating at all male-producing and male-biased intermediate temperatures results in a significant number of female offspring, an effect presumably due to aromatization of testosterone to oestradiol (OE2). Since testosterone serves as the precursor to both DHT and OE2, being metabolized by reductase and aromatase respectively, three experiments were conducted to determine whether various putative reductase and aromatase inhibitors would overcome the effect of incubation temperature. First, while administration of testosterone to eggs incubating at all male-producing and male-biased intermediate temperatures produced females in a dose- and temperature-dependent manner, significant numbers of intersex individuals resulted from high dosage testosterone treatment to eggs incubating at a female-biased intermediate temperature. The reductase inhibitors 4MA and MK906 were capable of producing female offspring if administered at intermediate temperatures, but not in a dose-dependent fashion. Administration of the aromatase inhibitors CGS16949A and CGS20267 resulted in male offspring at both female-biased intermediate and at all female-producing temperatures in a dose-dependent fashion. Second, similar findings were obtained with combined doses of testosterone and reductase or aromatase inhibitors. Combined treatment of eggs at male-biased intermediate incubation temperatures with testosterone and reductase inhibitor resulted in female hatchlings, whereas combined treatment of testosterone and aromatase inhibitor at both female-biased intermediate and at all female-producing temperatures resulted in male hatchlings.(ABSTRACT TRUNCATED AT 400 WORDS)
Olivier Verneau - One of the best experts on this subject based on the ideXlab platform.
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© 2015 The Author(s). Journal compilation © 2015 REABIC Open Access
2015Co-Authors: Leon Meyer, Louis Du Preez, Elodie Bonneau, Laurent Héritier, Marc Franch Quintana, Aitor Valdeón, Amel Sadaoui, Nadia Kechemir-issad, Carmen Palacios, Olivier VerneauAbstract:Parasite host-switching from the invasive American Red-Eared Slider, Trachemys scripta elegans, to the native Mediterranean pond turtle, Mauremys leprosa, in natural environment
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Open Access Research Article CORRECTED PROOF
2015Co-Authors: Leon Meyer, Louis Du Preez, Elodie Bonneau, Laurent Héritier, Marc Franch Quintana, Aitor Valdeón, Amel Sadaoui, Nadia Kechemir-issad, Carmen Palacios, Olivier VerneauAbstract:Parasite host-switching from the invasive American Red-Eared Slider, Trachemys scripta elegans, to the native Mediterranean pond turtle, Mauremys leprosa, in natural environment
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Parasite host-switching from the invasive American Red-Eared Slider, Trachemys scripta elegans, to the native Mediterranean pond turtle, Mauremys leprosa, in natural environments
Aquatic Invasions, 2015Co-Authors: Leon Meyer, Louis Du Preez, Elodie Bonneau, Laurent Héritier, Aitor Valdeón, Amel Sadaoui, Nadia Kechemir-issad, Carmen Palacios, Marc Franch Quintana, Olivier VerneauAbstract:The Red-Eared Slider turtle, Trachemys scripta elegans, is among the most over-exploited animals and is still exported annually from the USA all over the world. Once introduced into its new environment, feral populations may arise and pose threats to local biodiversity and ecosystem functioning. In France, it is in fact considered as a risk for the Mediterranean pond turtle, Mauremys leprosa, and the European pond turtle, Emys orbicularis, as they may compete for resources and habitat. Freshwater turtles are also host to a variety of parasites including protozoans and helminths. When introduced turtles escape, parasites may spread to native species. The objective of this study was to document the extent of platyhelminth invasions from T. s. elegans to natural M. leprosa populations in northern Spain and southern France and to evaluate the risks that parasite host-switching may pose on indigenous freshwater turtle species. From DNA barcoding analysis based on the sequencing of the Cytochrome c Oxidase I gene, the Bayesian tree and p-distance comparisons of closely related haplotypes revealed a greater polystome richness within M. leprosa than expected, suggesting that host switching may take place in natural environments. Because these parasites most typically infest American turtles like Chrysemys picta marginata and Graptemys pseudogeographica in their natural home range and because parasites were also found within T. s. elegans feral populations, it is suggested that the Red-Eared Slider would serve as a carrier for a variety of not strictly host-specific polystomes that are transmitted to M. leprosa throughout the south of France. The global trade in freshwater turtles thus provides opportunity for parasites to be transported to new destinations which could impact the physiology, behavior and survival of native turtle species.
Ding L. - One of the best experts on this subject based on the ideXlab platform.
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Early-life intestinal microbiome in Trachemys scripta elegans analyzed using 16S rRNA sequencing
2020Co-Authors: Peng Q., Chen Y., Ding L., Zhao Z., Yan P., Storey K. B.), Shi H., Hong M.Abstract:During the early-life period, the hatchlings of Red-Eared Slider turtles (Trachemys scripta elegans) rely on their own post-hatching internal yolk for several days before beginning to feed. The gut microbiome is critical for the adaptation of organisms to new environ- ments, but, to date, how the microbiome taxa are assembled during early life of the turtle is unknown. In this study, the intestinal microbiome of Red-Eared Slider hatchlings (fed on commercial particle food
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Early-life intestinal microbiome in Trachemys scripta elegans analyzed using 16S rRNA sequencing
'PeerJ', 2020Co-Authors: Peng Q., Chen Y., Ding L., Zhao Z., Yan P., Storey K. B.), Shi H., Hong M.Abstract:During the early-life period, the hatchlings of Red-Eared Slider turtles (Trachemys scripta elegans) rely on their own post-hatching internal yolk for several days before beginning to feed. The gut microbiome is critical
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Adenosine Monophosphate-Activated Protein Kinase Signaling Regulates Lipid Metabolism in Response to Salinity Stress in the Red-Eared Slider Turtle Trachemys scripta elegans
'Frontiers Media SA', 2019Co-Authors: Hong M., Storey K. B.), Shi H., Li N., Li J., Li W., Liang L., Li Q., Wang R., Ding L.Abstract:Aquatic animals have developed various mechanisms to live in either hyperionic or hypoionic environments, and, as such, not many species are capable of surviving in both. The Red-Eared Slider turtle, Trachemys scripta elegans, a well-known freshwater species, has recently been found to invade and inhabit brackish water. Herein, we focus on some of the metabolic adaptations that are required to survive and cope with salinity stress. The regulation of the adenosine monophosphate (AMP)-activated protein kinase (AMPK), a main cellular “energy sensor,” and its influence on lipid metabolism were evaluated with a comparison of three groups of turtles: controls in freshwater, and turtles held in water of either 5 salinity (S5) or 15 salinity (S15) with sampling at 6, 24, and 48 h and 30 days of exposure. When subjected to elevated salinities of 5 or 15, AMPK mRNA levels and AMPK enzyme activity increased strongly. In addition, the high expression of the peroxisome proliferator activated receptor-α (PPARα) transcription factor that, in turn, facilitated upregulation of target genes including carnitine palmitoyltransferase (CPT) and acyl-CoA oxidase (ACO). Furthermore, the expression of transcription factors involved in lipid synthesis such as the carbohydrate-responsive element-binding protein (ChREBP) and sterol regulatory element-binding protein 1c (SREBP-1c) was inhibited, and two of their target genes, acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), were significantly decreased. Moreover, exposure to saline environments also increased plasma triglyceride (TG) content. Interestingly, the content of low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) in plasma was markedly higher than the control in the S15 group after 30 days, which indicated that lipid metabolism was disrupted by chronic exposure to high salinity. These findings demonstrate that activation of AMPK might regulate lipid metabolism in r
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Comparative analysis of the liver transcriptome in the Red-Eared Slider Trachemys scripta elegans under chronic salinity stress
'PeerJ', 2019Co-Authors: Hong M., Storey K. B.), Shi H., Li N., Li W., Jiang A., Ding L.Abstract:The Red-Eared Slider (Trachemys scripta elegans), identified as one of the 100 most invasive species in the world, is a freshwater turtle originally from the eastern United States and northeastern Mexico. Field investigations have shown that T. s. elegans can survive and lay eggs in saline habitats. In order to understand the molecular mechanisms of salinity adaptation, high-throughput RNA-Seq was utilized to identify the changes in gene expression profiles in the liver of T. s. elegans in response to elevated salinity. We exposed individuals to 0, 5, or 15 psu (practical salinity units) for 30 days. A total of 157.21 million reads were obtained and assembled into 205138 unigenes with an average length of 620 bp and N50 of 964 bp. Of these, 1019 DEGs (differentially expressed genes) were found in the comparison of 0 vs. 5 psu, 1194 DEGs in 0 vs. 15 psu and 1180 DEGs in 5 vs. 15 psu, which are mainly related to macromolecule metabolic process, ion transport, oxidoreductase activity and generation of precursor metabolites and energy by GO (Gene Ontology) enrichment analyses. T. s. elegans can adapt itself into salinity by balancing the entry of sodium and chloride ions via the up-regulation expression genes of ion transport (potassium voltage-gated channel subfamily H member 5, KCNH5; erine/threonine-protein kinase 32, STK32; salt-inducible kinase 1, SIK1; adiponectin, ACDC), and by accumulating plasma urea and free amino acid via the up-regulation expression genes of amino acid metabolism (ornithine decarboxylase antizyme 3, OAZ3; glutamine synthetase, GLUL; asparaginase-like protein 1b, ASRGL; L-amino-acid oxidase-like, LAAO; sodium-dependent neutral amino acid transporter B, SLC6A15s; amino acid permease, SLC7A9) in response to osmotic regulation. An investment of energy to maintain their homeostatic balance is required to salinity adaptation, therefore, the genes related to energy production and conversion (F-ATPase protein 6, ATP6; cytochrome c oxidase subunit I, COX1; cytochrome c oxidase subunit III, COX3; cytochrome b, CYTb; cytochrome P450 17A1, CYP17A1) were up-regulated with the increase of gene expression associated with lipid metabolism (apolipoprotein E precursor, APoE; coenzyme Q-binding protein, CoQ10; high-density lipoprotein particle, SAA) and carbohydrate metabolism (HK, MIP). These findings improve our understanding of the underlying molecular mechanisms involved in salinity adaptationand provide general guidance to illuminate the invasion potential of T. s. elegans into saline environments
