72 research outputs found
Comparing Microbiome Sampling Methods in a Wild Mammal: Fecal and Intestinal Samples Record Different Signals of Host Ecology, Evolution
Processing of multimodal information is essential for an organism to respond to environmental events. However, how multimodal integration in neurons translates into behavior is far from clear. Here, we investigate integration of biologically relevant visual and auditory information in the goldfish startle escape system in which paired Mauthner-cells (M-cells) initiate the behavior. Sound pips and visual looms as well as multimodal combinations of these stimuli were tested for their effectiveness of evoking the startle response. Results showed that adding a low intensity sound early during a visual loom (low visual effectiveness) produced a supralinear increase in startle responsiveness as compared to an increase expected from a linear summation of the two unimodal stimuli. In contrast, adding a sound pip late during the loom (high visual effectiveness) increased responsiveness consistent with a linear multimodal integration of the two stimuli. Together the results confirm the Inverse Effectiveness Principle (IEP) of multimodal integration proposed in other species. Given the well-established role of the M-cell as a multimodal integrator, these results suggest that IEP is computed in individual neurons that initiate vital behavioral decisions
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Population genetic structure and habitat connectivity for jaguar (Panthera onca) conservation in Central Belize
Background
Connectivity among jaguar (Panthera onca) populations will ensure natural gene flow and the long-term survival of the species throughout its range. Jaguar conservation efforts have focused primarily on connecting suitable habitat in a broad-scale. Accelerated habitat reduction, human-wildlife conflict, limited funding, and the complexity of jaguar behaviour have proven challenging to maintain connectivity between populations effectively. Here, we used non-invasive genetic sampling and individual-based conservation genetic analyses to assess genetic diversity and levels of genetic connectivity between individuals in the Cockscomb Basin Wildlife Sanctuary and the Maya Forest Corridor. We used expert knowledge and scientific literature to develop models of landscape permeability based on circuit theory with fine-scale landscape features as ecosystem types, distance to human settlements and roads to predict the most probable jaguar movement across central Belize.
Results
We used 12 highly polymorphic microsatellite loci to identify 50 individual jaguars. We detected high levels of genetic diversity across loci (HE = 0.61, HO = 0.55, and NA = 9.33). Using Bayesian clustering and multivariate models to assess gene flow and genetic structure, we identified one single group of jaguars (K = 1). We identified critical areas for jaguar movement that fall outside the boundaries of current protected areas in central Belize. We detected two main areas of high landscape permeability in a stretch of approximately 18 km between Sittee River Forest Reserve and Manatee Forest Reserve that may increase functional connectivity and facilitate jaguar dispersal from and to Cockscomb Basin Wildlife Sanctuary. Our analysis provides important insights on fine-scale genetic and landscape connectivity of jaguars in central Belize, an area of conservation concern.
Conclusions
The results of our study demonstrate high levels of relatively recent gene flow for jaguars between two study sites in central Belize. Our landscape analysis detected corridors of expected jaguar movement between the Cockscomb Basin Wildlife Sanctuary and the Maya Forest Corridor. We highlight the importance of maintaining already established corridors and consolidating new areas that further promote jaguar movement across suitable habitat beyond the boundaries of currently protected areas. Continued conservation efforts within identified corridors will further maintain and increase genetic connectivity in central Belize
MSG-Fast: Metagenomic shotgun data fast annotation using microbial gene catalogs
Background: Current methods used for annotating metagenomics shotgun sequencing (MGS) data rely on a computationally intensive and low-stringency approach of mapping each read to a generic database of proteins or reference microbial genomes.
Results: We developed MGS-Fast, an analysis approach for shotgun whole-genome metagenomic data utilizing Bowtie2 DNA-DNA alignment of reads that is an alternative to using the integrated catalog of reference genes database of well-annotated genes compiled from human microbiome data. This method is rapid and provides high-stringency matches (\u3e90% DNA sequence identity) of the metagenomics reads to genes with annotated functions. We demonstrate the use of this method with data from a study of liver disease and synthetic reads, and Human Microbiome Project shotgun data, to detect differentially abundant Kyoto Encyclopedia of Genes and Genomes gene functions in these experiments. This rapid annotation method is freely available as a Galaxy workflow within a Docker image.
Conclusions: MGS-Fast can confidently transfer functional annotations from gene databases to metagenomic reads, with speed and accuracy
Human Stiff-Person Syndrome IgG Induces Anxious Behavior in Rats
Background: Anxiety is a heterogeneous behavioral domain playing a role in a variety of neuropsychiatric diseases. While anxiety is the cardinal symptom in disorders such as panic disorder, co-morbid anxious behavior can occur in a variety of diseases. Stiff person syndrome (SPS) is a CNS disorder characterized by increased muscle tone and prominent agoraphobia and anxiety. Most patients have high-titer antibodies against glutamate decarboxylase (GAD) 65. The pathogenic role of these autoantibodies is unclear. Methodology/Principal Findings: We re-investigated a 53 year old woman with SPS and profound anxiety for GABA-A receptor binding in the amygdala with (11)C-flumazenil PET scan and studied the potential pathogenic role of purified IgG from her plasma filtrates containing high-titer antibodies against GAD 65. We passively transferred the IgG fraction intrathecally into rats and analyzed the effects using behavioral and in vivo electrophysiological methods. In cell culture, we measured the effect of patient IgG on GABA release from hippocampal neurons. Repetitive intrathecal application of purified patient IgG in rats resulted in an anxious phenotype resembling the core symptoms of the patient. Patient IgG selectively bound to rat amygdala, hippocampus, and frontal cortical areas. In cultured rat hippocampal neurons, patient IgG inhibited GABA release. In line with these experimental results, the GABA-A receptor binding potential was reduced in the patient’s amygdala/hippocampus complex. No motor abnormalities were found in recipient rats. Conclusion/Significance: The observations in rats after passive transfer lead us to propose that anxiety-like behavior can be induced in rats by passive transfer of IgG from a SPS patient positive for anti-GAD 65 antibodies. Anxiety, in this case, thus may be an antibody-mediated phenomenon with consecutive disturbance of GABAergic signaling in the amygdala region
STRUCTURE - Belize Felids - Wultsch et al. 2014
STRUCTURE file for the manuscript "Noninvasive Individual and Species Identification of Jaguars (Panthera onca), Pumas (Puma concolor) and Ocelots (Leopardus pardalis) in Belize, Central America using Cross-Species Microsatellites and Fecal DNA". The file includes microsatellite genotype data for the three target species detected in Belize for this study
16S_BZ_Felids
Alignment of 16S (L2513, H2714, Kitano et al. 2007) sequence data in nexus format. Sample ID is tied to selected specimen (fecal DNA samples) of three Neotropical felids (jaguar, Panthera onca; puma, Puma concolor; ocelot, Leopardus pardalis) collected in Belize, Central America
ATP6_BZ_Felids
Alignment of adenosine triphosphate-6 (ATP6-DF3, ATP6-DR2, Chaves et al. 2012) sequence data in nexus format. Sample ID is tied to selected specimen (fecal DNA samples) of three Neotropical felids (jaguar, Panthera onca; puma, Puma concolor; ocelot, Leopardus pardalis) collected in Belize, Central America
STRUCTURE - Belize Felids - Wultsch et al. 2014
STRUCTURE file for the manuscript "Noninvasive Individual and Species Identification of Jaguars (Panthera onca), Pumas (Puma concolor) and Ocelots (Leopardus pardalis) in Belize, Central America using Cross-Species Microsatellites and Fecal DNA". The file includes microsatellite genotype data for the three target species detected in Belize for this study
16Scp_BZ_Felids
Alignment of 16Scp (16Scp-F, 16Scp-F, Kitano et al. 2007) sequence data in nexus format. Sample ID is tied to selected specimen (fecal DNA samples) of three Neotropical felids (jaguar, Panthera onca; puma, Puma concolor; ocelot, Leopardus pardalis) collected in Belize, Central America
A Comparative Analysis of Genetic Diversity and Structure in Jaguars (<i>Panthera onca</i>), Pumas (<i>Puma concolor</i>), and Ocelots (<i>Leopardus pardalis</i>) in Fragmented Landscapes of a Critical Mesoamerican Linkage Zone
<div><p>With increasing anthropogenic impact and landscape change, terrestrial carnivore populations are becoming more fragmented. Thus, it is crucial to genetically monitor wild carnivores and quantify changes in genetic diversity and gene flow in response to these threats. This study combined the use of scat detector dogs and molecular scatology to conduct the first genetic study on wild populations of multiple Neotropical felids coexisting across a fragmented landscape in Belize, Central America. We analyzed data from 14 polymorphic microsatellite loci in 1053 scat samples collected from wild jaguars (<i>Panthera onca</i>), pumas (<i>Puma concolor</i>), and ocelots (<i>Leopardus pardalis</i>). We assessed levels of genetic diversity, defined potential genetic clusters, and examined gene flow for the three target species on a countrywide scale using a combination of individual- and population-based analyses. Wild felids in Belize showed moderate levels of genetic variation, with jaguars having the lowest diversity estimates (<i>H</i><sub><i>E</i></sub> = 0.57 ± 0.02; <i>A</i><sub><i>R</i></sub> = 3.36 ± 0.09), followed by pumas (<i>H</i><sub><i>E</i></sub> = 0.57 ± 0.08; <i>A</i><sub><i>R</i></sub> = 4.20 ± 0.16), and ocelots (<i>H</i><sub><i>E</i></sub> = 0.63 ± 0.03; <i>A</i><sub><i>R</i></sub> = 4.16 ± 0.08). We observed low to moderate levels of genetic differentiation for all three target species, with jaguars showing the lowest degree of genetic subdivision across the country, followed by ocelots and pumas. Although levels of genetic diversity and gene flow were still fairly high, we detected evidence of fine-scale genetic subdivision, indicating that levels of genetic connectivity for wild felids in Belize are likely to decrease if habitat loss and fragmentation continue at the current rate. Our study demonstrates the value of understanding fine-scale patterns of gene flow in multiple co-occurring felid species of conservation concern, which is vital for wildlife movement corridor planning and prioritizing future conservation and management efforts within human-impacted landscapes.</p></div
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