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PeerJ 2024The Jambato Harlequin toad (), a formerly abundant species in the Andes of Ecuador, faced a dramatic population decline in the 1980s, with its last recorded sighting in...
The Jambato Harlequin toad (), a formerly abundant species in the Andes of Ecuador, faced a dramatic population decline in the 1980s, with its last recorded sighting in 1988. The species was considered Extinct by the IUCN until 2016, when a fortuitous discovery of one Jambato by a local boy reignited hope. In this study, we present findings from an investigation conducted in the Angamarca parish, focusing on distribution, abundance, habitat preferences, ecology, disease susceptibility, and dietary habits of the species. In one year we identified 71 individuals at different stages of development in various habitats, with a significant presence in agricultural mosaic areas and locations near water sources used for crop irrigation, demonstrating the persistence of the species in a complex landscape, with considerable human intervention. The dietary analysis based on fecal samples indicated a diverse prey selection, primarily comprising arthropods such as Acari, Coleoptera, and ants. Amphibian declines have been associated with diseases and climate change; notably, our study confirmed the presence of the pathogen (), but, surprisingly, none of the infected Jambatos displayed visible signs of illness. When analyzing climatic patterns, we found that there are climatic differences between historical localities and Angamarca; the temporal analysis also exposes a generalized warming trend. Finally, in collaboration with the local community, we developed a series of management recommendations for terrestrial and aquatic environments occupied by the Jambato.
Topics: Animals; Ecuador; Bufonidae; Ecosystem; Batrachochytrium; Conservation of Natural Resources
PubMed: 38915382
DOI: 10.7717/peerj.17344 -
Scientific Reports Jun 2024Reintroduction efforts are increasingly used to mitigate biodiversity losses, but are frequently challenged by inadequate planning and uncertainty. High quality...
Reintroduction efforts are increasingly used to mitigate biodiversity losses, but are frequently challenged by inadequate planning and uncertainty. High quality information about population status and threats can be used to prioritize reintroduction and restoration efforts and can transform ad hoc approaches into opportunities for improving conservation outcomes at a landscape scale. We conducted comprehensive environmental DNA (eDNA) and visual encounter surveys to determine the distribution of native and non-native aquatic species in two high-priority watersheds to address key uncertainties-such as the distribution of threats and the status of existing populations-inherent in restoration planning. We then used these occurrence data to develop a menu of potential conservation actions and a decision framework to benefit an endangered vertebrate (foothill yellow-legged frog, Rana boylii) in dynamic stream systems. Our framework combines the strengths of multiple methods, allowing managers and conservation scientists to incorporate conservation science and site-specific knowledge into the planning process to increase the likelihood of achieving conservation goals.
Topics: Animals; Conservation of Natural Resources; Rivers; DNA, Environmental; Biodiversity; Endangered Species; Ecosystem; Ranidae
PubMed: 38906892
DOI: 10.1038/s41598-024-64612-5 -
PloS One 2024[This corrects the article DOI: 10.1371/journal.pone.0258594.].
[This corrects the article DOI: 10.1371/journal.pone.0258594.].
PubMed: 38905207
DOI: 10.1371/journal.pone.0306069 -
Communications Biology Jun 2024DNA methylation maintenance is essential for cell fate inheritance. In differentiated cells, this involves orchestrated actions of DNMT1 and UHRF1. In mice, the...
DNA methylation maintenance is essential for cell fate inheritance. In differentiated cells, this involves orchestrated actions of DNMT1 and UHRF1. In mice, the high-affinity binding of DPPA3 to the UHRF1 PHD finger regulates UHRF1 chromatin dissociation and cytosolic localization, which is required for oocyte maturation and early embryo development. However, the human DPPA3 ortholog functions during these stages remain unclear. Here, we report the structural basis for human DPPA3 binding to the UHRF1 PHD finger. The conserved human DPPA3 VRT motif binds to the acidic surface of UHRF1 PHD finger, whereas mouse DPPA3 binding additionally utilizes two unique α-helices. The binding affinity of human DPPA3 for the UHRF1 PHD finger was weaker than that of mouse DPPA3. Consequently, human DPPA3, unlike mouse DPPA3, failed to inhibit UHRF1 chromatin binding and DNA remethylation in Xenopus egg extracts effectively. Our data provide novel insights into the distinct function and structure of human DPPA3.
Topics: Animals; Ubiquitin-Protein Ligases; Humans; CCAAT-Enhancer-Binding Proteins; Mice; Protein Binding; PHD Zinc Fingers; DNA Methylation; Chromatin; Amino Acid Sequence; Xenopus laevis
PubMed: 38898124
DOI: 10.1038/s42003-024-06434-9 -
Anais Da Academia Brasileira de Ciencias 2024The following work presents the first study applying the passive acoustic monitoring of anurans at lotic environments for a long time. This study aims to test the...
The following work presents the first study applying the passive acoustic monitoring of anurans at lotic environments for a long time. This study aims to test the efficiency of the passive acoustic monitoring method and active monitoring in detecting anurans in lotic environments of Itinguçu State Park. Specifically, we tested whether species richness differs when comparing active and passive monitoring surveys. Therefore, this study aims to test the efficiency of the passive acoustic monitoring method and active monitoring in detecting anurans in lotic environments of the Itinguçu State Park. The passive acoustic monitoring period was 72 uninterrupted hours at each collection point with intervals of 45 days. Finally, species richness was calculated, and the efficiency of the methods was compared in different scenarios. Our results demonstrated that the park has species that vocalize day and night, but most at night, there is overlapping acoustic niche; waterfall environments harm the quality of recordings; and in lotic environments the active monitoring method was more efficient than the passive acoustic monitoring in all sampling scales. Although the passive acoustic monitoring was not as efficient in a low temporal scale, it tends to increase in efficiency with longer sampling duration.
Topics: Animals; Peru; Acoustics; Anura; Parks, Recreational; Environmental Monitoring; Vocalization, Animal; Biodiversity
PubMed: 38896695
DOI: 10.1590/0001-3765202420231057 -
Molecules (Basel, Switzerland) May 2024With the global population on the rise, an escalating interest exists in environmentally sustainable and friendly protein sources. Insects have emerged as multifaceted...
With the global population on the rise, an escalating interest exists in environmentally sustainable and friendly protein sources. Insects have emerged as multifaceted resources, viewed not only as potential food items, but also as sources of traditional medicines and proteins. This study utilized response surface methodology (RSM) to ascertain the optimal extraction conditions for proteins from used in toad feeding, denoted as MDPs-T. The yield of MDPs-T was elevated to 18.3% ± 0.2% under these optimized conditions. Subsequently, the particle size, ζ-potentials, and structures of MDPs-T were analyzed and compared with the proteins derived from fed on a normal diet (MDPs-ND). This comparative analysis utilized a range of advanced techniques, involving UV spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), high-performance gel permeation chromatography (HPGPC), and scanning electron microscopy (SEM). The outcomes have revealed a marginal disparity in the physical and chemical properties between MDPs-T and MDPs-ND. Derosination led to a reduction in the particle size of the MDPs by 10.98% to 62.81%. MDPs-T exhibited a higher proportion of low-molecular-weight components relative to MDPs-ND. Additionally, in a comparative analysis of amino acids, MDPs-T displayed a greater abundance of essential and total amino acids relative to MDPs-ND. Consequently, MDPs-T holds potential as a valuable food supplement for human consumption or as a nutrient-rich feed supplement for animals.
Topics: Animals; Houseflies; Insect Proteins; Larva; Spectroscopy, Fourier Transform Infrared; Bufonidae; X-Ray Diffraction; Particle Size; Animal Feed
PubMed: 38893470
DOI: 10.3390/molecules29112595 -
International Journal of Molecular... May 2024Extreme weather poses huge challenges for animals that must adapt to wide variations in environmental temperature and, in many cases, it can lead to the local...
Extreme weather poses huge challenges for animals that must adapt to wide variations in environmental temperature and, in many cases, it can lead to the local extirpation of populations or even the extinction of an entire species. Previous studies have found that one element of amphibian adaptation to environmental stress involves changes in mitochondrial gene expression at low temperatures. However, to date, comparative studies of gene expression in organisms living at extreme temperatures have focused mainly on nuclear genes. This study sequenced the complete mitochondrial genomes of five Asian hylid frog species: , , , and . It compared the phylogenetic relationships within the Hylidae family and explored the association between mitochondrial gene expression and evolutionary adaptations to cold stress. The present results showed that in , transcript levels of 12 out of 13 mitochondria genes were significantly reduced under cold exposure ( < 0.05); hence, we put forward the conjecture that . adapts by entering a hibernation state at low temperature. In , the transcripts of 10 genes (, , , , , , , , and ) were significantly reduced in response to cold exposure, and five mitochondrial genes in (, , , and ) also showed significantly reduced expression and transcript levels under cold conditions. By contrast, transcript levels of and in . were significantly increased at low temperatures, possibly related to the narrow distribution of this species primarily at low latitudes. Indeed, has little ability to adapt to low temperature (4 °C), or maybe to enter into hibernation, and it shows metabolic disorder in the cold. The present study demonstrates that the regulatory trend of mitochondrial gene expression in amphibians is correlated with their ability to adapt to variable climates in extreme environments. These results can predict which species are more likely to undergo extirpation or extinction with climate change and, thereby, provide new ideas for the study of species extinction in highly variable winter climates.
Topics: Animals; Genome, Mitochondrial; Anura; Phylogeny; Cold-Shock Response; Cold Temperature; Adaptation, Physiological; Gene Expression Regulation
PubMed: 38892163
DOI: 10.3390/ijms25115967 -
International Journal of Molecular... May 2024The sodium-glucose co-transporter-2 (SGLT2) inhibitor dapagliflozin is increasingly used in the treatment of diabetes and heart failure. Dapagliflozin has been...
The sodium-glucose co-transporter-2 (SGLT2) inhibitor dapagliflozin is increasingly used in the treatment of diabetes and heart failure. Dapagliflozin has been associated with reduced incidence of atrial fibrillation (AF) in clinical trials. We hypothesized that the favorable antiarrhythmic outcome of dapagliflozin use may be caused in part by previously unrecognized effects on atrial repolarizing potassium (K) channels. This study was designed to assess direct pharmacological effects of dapagliflozin on cloned ion channels K11.1, K1.5, K4.3, K2.1, K2.1, K3.1, and K17.1, contributing to , , , , and K currents. Human channels coded by , , , , , , and were heterologously expressed in oocytes, and currents were recorded using the voltage clamp technique. Dapagliflozin (100 µM) reduced K11.1 and K1.5 currents, whereas K2.1, K2.1, and K17.1 currents were enhanced. The drug did not significantly affect peak current amplitudes of K4.3 or K3.1 K channels. Biophysical characterization did not reveal significant effects of dapagliflozin on current-voltage relationships of study channels. In conclusion, dapagliflozin exhibits direct functional interactions with human atrial K channels underlying , , , and currents. Substantial activation of K2.1 and K17.1 currents could contribute to the beneficial antiarrhythmic outcome associated with the drug. Indirect or chronic effects remain to be investigated in vivo.
Topics: Humans; Glucosides; Sodium-Glucose Transporter 2 Inhibitors; Benzhydryl Compounds; Animals; Xenopus laevis; Potassium Channels; Oocytes; Sodium-Glucose Transporter 2
PubMed: 38891889
DOI: 10.3390/ijms25115701 -
Animals : An Open Access Journal From... May 2024Chemical communication is an important mode of communication in the courtship and breeding processes of amphibians. In caudates, multiple components of sexual pheromones...
Chemical communication is an important mode of communication in the courtship and breeding processes of amphibians. In caudates, multiple components of sexual pheromones have been identified and functionally verified. One of these pheromone systems is plethodontid modulating factor (PMF). In anurans, the pheromone called amplexin was found in nuptial pads of ranids and was considered a member of the PMF system, yet its bio-function has not been tested. In this study, we obtained 18 amplexin transcript sequences from nuptial pads of (Amphibia, Ranidae) by transcriptome sequencing and found that the proteins translated by these transcripts are diversified, hydrophilic, and relatively stable. We also acquired a amplexin isoform with the highest expression level in the transcriptome analysis through the prokaryotic expression system. Using two different animal behavioral experimental settings, we have tested the bio-function of the recombinant PMF protein (rPMF) in 's reproduction and found that the rPMF does not attract females but shortens the duration of amplexus significantly. This is the first study to verify the function of the PMF pheromone in Anura, indicating the pervasiveness of chemical communication during breeding in amphibians.
PubMed: 38891597
DOI: 10.3390/ani14111550 -
PeerJ 2024Amphibians are experiencing declines globally, with emerging infectious diseases as one of the main causes. Haematological parameters present a useful method for...
Amphibians are experiencing declines globally, with emerging infectious diseases as one of the main causes. Haematological parameters present a useful method for determining the health status of animals and the effects of particular diseases, but the interpretation of differential cell counts relies on knowing the normal ranges for the species and factors that can affect these counts. However, there is very little data on either normal haematological parameters or guides for blood cell types for free-ranging frog species across the world. This study aims to 1) create a visual guide for three different Australian frog species: , , and , 2) determine the proportions of erythrocytes to leukocytes and 3) differential leukocytes within blood smears from these three species and 4) assess the association between parasites and differential counts. We collected blood samples from free-ranging frogs and analysed blood smears. We also looked for ectoparasites and tested for the fungal disease chytridiomycosis. Overall, we found that the differentials of erythrocytes to leukocytes were not affected by species, but the proportions of different leukocytes did vary across species. For example, while lymphocytes were the most common type of leukocyte across the three species, eosinophils were relatively common in but rarely present in the other two species. We noted chytridiomycosis infection as well as ectoparasites present in some individuals but found no effect of parasites on blood parameters. Our results add baseline haematological parameters for three Australian frog species and provide an example of how different frog species can vary in their differential blood cell counts. More information is needed on frog haematological data before these parameters can be used to determine the health status of wild or captive frogs.
Topics: Animals; Anura; Australia; Reference Values; Erythrocytes; Blood Cell Count; Hematologic Tests; Species Specificity; Leukocyte Count; Male
PubMed: 38860213
DOI: 10.7717/peerj.17406