Search Results (4)

Limited information exists on the diet of snow leopards (SL), factors affecting livestock mortality, and local attitudes toward SL conservation in the Manaslu Conservation Area (MCA), Nepal. Therefore, we aim to investigate the dietary preferences of SL, the factors influencing livestock mortality, and local conservation attitudes. From November 2021 to January 2022, 23 SL scats were collected along 24 transects (total length: 21.6 km) in MCA. Camera traps, set within 4 km × 4 km grids at 28 stations for 661 trap nights, were used to assess prey availability. Jacobs’ index calculated prey preference, while a Generalized Linear Mixed Model (GLMM) assessed factors linked to livestock depredation. Additionally, 65 households from two villages were randomly selected in a survey on depredation and conservation attitudes. Scat analysis identified six wild prey species, including pika (Ochotona sp.), Himalayan tahr (Hemitragus jemlahicus), and blue sheep (Pseudois nayaur), as well as three domestic species: ox/cow, yak, and horse. Himalayan tahr had the highest presence in the SL diet (40%). Despite pika having the highest Relative Abundance Index (RAI), SL strongly preferred horses and avoided pika. Larger prey, such as horses, Himalayan tahr, and blue sheep, were highly preferred. Households with more livestock experienced higher depredation rates. Local attitudes toward SL conservation were generally positive, with an average score of 2.59. We recommend an integrated SL conservation plan in MCA, incorporating local participation, income diversification, and employment programs to mitigate conflicts and promote coexistence. Full article

Telomeres in Drosophila melanogaster, which have inspired a large part of Sergio Pimpinelli work, are similar to those of other eukaryotes in terms of their function. Yet, their length maintenance relies on the transposition of the specialized retrotransposons Het-A, TART, and TAHRE, rather than on the activity of the enzyme telomerase as it occurs in most other eukaryotic organisms. The length of the telomeres in Drosophila thus depends on the number of copies of these transposable elements. Our previous work has led to the isolation of a dominant mutation, Tel¹, that caused a several-fold elongation of telomeres. In this study, we molecularly identified the Tel¹ mutation by a combination of transposon-induced, site-specific recombination and next-generation sequencing. Recombination located Tel¹ to a 15 kb region in 92A. Comparison of the DNA sequence in this region with the Drosophila Genetic Reference Panel of wild-type genomic sequences delimited Tel¹ to a 3 bp deletion inside intron 8 of Ino80. Furthermore, CRISPR/Cas9-induced deletions surrounding the same region exhibited the Tel¹ telomere phenotype, confirming a strict requirement of this intron 8 gene sequence for a proper regulation of Drosophila telomere length. Full article

The present study aims to use behavioral responses of the freshwater planarian Girardia tigrina to assess the impact of anthropogenic activities on the aquatic ecosystem of the watershed Araguaia-Tocantins (Tocantins, Brazil). Behavioral responses are integrative and cumulative tools that reflect changes in energy allocation in organisms. Thus, feeding rate and locomotion velocity (pLMV) were determined to assess the effects induced by the laboratory exposure of adult planarians to water samples collected in the region of Tocantins-Araguaia, identifying the sampling points affected by contaminants. Furthermore, physicochemical and microbiological parameters, as well as the presence of inorganic compounds (dissolved aluminum, total barium, total chloride, dissolved iron, total fluoride, total manganese, nitrates, nitric nitrogen, total sulfate, total zinc) and surfactants, were determined on each specific sampling point. The behavioral biomarkers (feeding rate and pLMV) of the freshwater planarians were significantly decreased when organisms were exposed to water samples from four municipalities (Formoso do Araguaia, Lagoa da Confusão, Gurupi and Porto Nacional), sites of the Tocantins-Araguaia hydrographic region—TAHR. Both behavioral biomarkers decreased up to ~37–39% compared to organisms in ASTM medium only. Our results showed that these behavioral biomarkers can be used for fast screening monitoring of environmental samples of freshwater ecosystems, since a decrease in feeding rate and locomotor activity was observed in sites impacted by anthropogenic activities. However, the absence of effects observed in some sampling points does not represent the absence of contamination, since several other classes of contaminants were not determined. In these negative results, the absence of deleterious effects on behavioral biomarkers might only be indicative that the potential presence of contaminants on such sites does not significantly affect the performance of planarians. This fast screening approach seems to be useful to determine contaminated sites in freshwater ecosystems for biomonitoring purposes. This knowledge will help to develop biomonitoring programs and to decide appropriate sampling sites and analysis. Full article

Drosophila and extant species are the best-studied telomerase exception. In this organism, telomere elongation is coupled with targeted retrotransposition of Healing Transposon (HeT-A) and Telomere Associated Retrotransposon (TART) with sporadic additions of Telomere Associated and HeT-A Related (TAHRE), all three specialized non-Long Terminal Repeat (non-LTR) retrotransposons. These three very special retroelements transpose in head to tail arrays, always in the same orientation at the end of the chromosomes but never in interior locations. Apparently, retrotransposon and telomerase telomeres might seem very different, but a detailed view of their mechanisms reveals similarities explaining how the loss of telomerase in a Drosophila ancestor could successfully have been replaced by the telomere retrotransposons. In this review, we will discover that although HeT-A, TART, and TAHRE are still the only examples to date where their targeted transposition is perfectly tamed into the telomere biology of Drosophila, there are other examples of retrotransposons that manage to successfully integrate inside and at the end of telomeres. Because the aim of this special issue is viral integration at telomeres, understanding the base of the telomerase exceptions will help to obtain clues on similar strategies that mobile elements and viruses could have acquired in order to ensure their survival in the host genome. Full article