Biology subjects

Etheridge, T.

Publications and source records attributed to Etheridge, T..

3 recordsLinked to original sources

bioRxiv2026

Development of species-specific real-time PCR assays for the identification of five European Rhinolophus bats.

The detection and monitoring of bat species using non-invasive sampling and molecular techniques has become increasingly popular in recent years. In Europe, these approaches have been applied to identify horseshoe bats of the genus Rhinolophus, which includes five species: R. hipposideros, R. ferrumequinum, R. euryale, R. mehelyi and R. blasii. While species-specific real-time PCR assays exist for R. ferrumequinum and R. hipposideros, no unified panel of real-time PCR assays currently enables the identification of all five European Rhinolophus species from non-invasively collected samples. Here, we developed five species-specific real-time PCR assays, each targeting interspecies nucleotide variation within the mitochondrial cytochrome b gene. To enhance single-base discrimination, RNase H-dependent PCR (rhPCR) primers were employed, incorporating cleavable blocked primers that require perfect complementarity for extension. The assays were applied to droppings non-invasively collected from 18 caves and one church in Serbia and Romania. Of the 149 samples analysed, 131 (88%) yielded successful amplification of Rhinolophus DNA. Detection probabilities for the three species identified in the field ranged from 0.49 to 0.82. Occupancy estimates varied, with R. euryale showing the highest (0.86; UI: 0.69-0.97) and R. mehelyi the lowest (0.23; UI: 0.08-0.43). The assays were capable of detecting up to three species concurrently within a single pooled sample (approximately 15 droppings). These assays are especially valuable for detecting R. mehelyi, given its rarity and uncertain distribution, and offer a robust tool for monitoring Rhinolophus populations across Europe.

ecology↗

bioRxiv2026

Microgravity affects the nervous system and aging in C. elegans through reduced tactile stimulation

Space travel is becoming accessible, yet our understanding of how space environment and microgravity ({micro}G) affect biology, physiology, and health remains incomplete. We investigated {micro}G effects on neuromuscular development and aging in Caenorhabditis elegans. Nematodes in {micro}G showed downregulation of genes related to synaptic signaling, dopamine response, locomotion, and cuticle development, with impaired synaptic vesicle dynamics, reduced motility, and shorter body lengths. Aged worms in {micro}G showed decreased collagen gene expression, increased motor neuron defects, synaptic vesicle accumulation and decreased release, and mitochondrial morphology collapse in body wall muscles, indicating accelerated aging. MEC-4 mechanoreceptor was identified as a key mediator of {micro}G-induced body length reduction and changes in extracellular matrix gene expression. {micro}G conditions suppressed mechanoreceptor genes, suggesting multiple mechanosensory systems are affected. Physical stimulation through culture medium with small beads in space mitigated many {micro}G-induced expression changes, including mechanoreceptors, neuromuscular defects, and aging-related phenotypes. These results highlight mechanical stimulis role in maintaining neuromuscular integrity during spaceflight and suggest restoring tactile input could counter health risks from reduced stimulation in long-term space missions. SIGNIFICACEWe found that microgravity ({micro}G) conditions suppress the expression of multiple mechanoreceptor genes in Caenorhabditis elegans, indicating that several mechanosensory systems are affected during spaceflight. Importantly, reintroducing physical stimulation by adding small beads to the culture medium in space partially reversed many of these {micro}G-induced gene expression changes. This intervention also mitigated neuromuscular defects and aging-related phenotypes observed under {micro}G conditions. Collectively, these findings underscore the essential role of mechanical stimuli in preserving neuromuscular integrity during space missions and suggest that restoring tactile input may be a promising strategy to counteract the health risks associated with reduced tactile stimulation during prolonged spaceflights.

systems biology↗

bioRxiv2020

Spaceflight Affects Neuronal Morphology and Alters Transcellular Degradation of Neuronal Debris in Adult Caenorhabditis elegans

Extended space travel, such as crewed missions to Mars and beyond, is a goal for both government space agencies and private companies. Research over the past decades, however, has shown that spaceflight poses risks to human health, including negative effects on musculoskeletal, cardiovascular, and immune systems. Details regarding effects on the nervous system have been less well described. The use of animal models holds great potential to identify and dissect conserved mechanisms of neuronal response to spaceflight. Here, we exploited the unique experimental advantages of the nematode Caenorhabditis elegans to explore how spaceflight affects adult neurons in vivo, at the single-cell level. We found that animals that lived 5 days of their adult life on the International Space Station exhibited considerable dendritic remodeling of the highly branched PVD neuron and modest morphological changes in touch receptor neurons when compared to ground control animals. Our results indicate hyperbranching as a common response of adult neurons to spaceflight. We also found that, in the presence of a neuronal proteotoxic stress, spaceflight promotes a remarkable accumulation of neuronal-derived waste in the surrounding tissues (especially hypodermis), suggesting an impaired transcellular degradation of debris that is released from neurons. Overall, our data reveal that spaceflight can significantly affect adult neuronal morphology and clearance of neuronal trash, highlighting the need to carefully assess the risks of long-duration spaceflight on the nervous system and to develop countermeasures to protect human health during space exploration.

neuroscience↗