Project description:Bats harbour various viruses without severe symptoms and act as natural reservoirs. This tolerance of bats toward viral infections is assumed to be originated from the uniqueness of their immune system. However, how the innate immune response varies between primates and bats remains unclear. To illuminate differences in innate immune responses among animal species, we performed a comparative single-cell RNA-sequencing analysis on peripheral blood mononuclear cells (PBMCs) from four species including Egyptian fruit bats inoculated with various infectious stimuli.
Project description:Hearing mediates many behaviors critical for survival in echolocating bats, including foraging and navigation. Although most mammals are susceptible to progressive age-related hearing loss, the evolution of biosonar, which requires the ability to hear low-intensity echoes from outgoing sonar signals, may have selected against the development of hearing deficits in bats. Many echolocating bats exhibit exceptional longevity and rely on acoustic behaviors for survival to old age; however relatively little is known about the aging bat auditory system. In this study, we used DNA methylation to estimate the ages of wild-caught big brown bats (Eptesicus fuscus) and measured hearing sensitivity in young and aging bats using auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). We found no evidence for hearing deficits in bats up to 12.5 years of age, demonstrated by comparable thresholds and similar ABR and DPOAE amplitudes across age groups. We additionally found no significant histological evidence for cochlear aging, with similar hair cell counts, afferent, and efferent innervation patterns in young and aging bats. Here we demonstrate that big brown bats show minimal evidence for age-related hearing loss and therefore represent informative models for investigating mechanisms that may preserve hearing function over a long lifetime.
2024-09-30 | GSE274777 | GEO
Project description:Gut microbiota of phyllostomid bats that span a breadth of diets
Project description:Bats are the only mammals capable of self-powered flying. Many bat species hibernate in winter. A reversible control of cerebral activities is critical for bats to accommodate a repeated torpor-arousal cycle during hibernation. Little is known about the molecular mechanism that regulates neuronal activities in torpid bats. In this study, brain proteins were fractionated and compared between torpid and active Rhinolophus ferrumequinum bats.
Project description:As the only truly flying mammals, bats use their unique wing formed from elongated digits connected by membranes to power their flight. The forelimb of bats consists of four elongated digits (digits II-V) and one shorter digit (digit I) that is morphologically similar to the hindlimb digits. Elongation of bat forelimb digits is thought to results from changes in the temporal and spatial expression of a number of developmental genes. As a result, comparing gene expression profiles between short and elongated digit morphologies of the fore- and hindlimbs may elucidate the molecular mechanisms underlying digit elongation in bats. Here, we performed a large-scale analysis of gene expression of forelimb digit I, forelimb digits II-V, and all five hindlimb digits in Myotis ricketti using digital gene expression tag profiling approach. Results of this study not only implicate several developmental genes as robust candidates underlying digit elongation in bats, but also provide a better understanding of the genes involved in autopodial development in general. A large-scale analysis of gene expression of 3 different parts of autopods in Myotis ricketti using digital gene expression tag profiling approach.
Project description:The only freely flying mammals, bats, develop a pair of dramatically elongated hands and broad wing membranes. It is hypothesized that alterations of many gene expressions result in the bat wing formation. However, it remains to be proved. Here, by mRNA-seq, we found that hundreds of genes are significantly high expressed in the elongating forelimb digits. mRNA-seq data of 14 autopod samples from embryonic bats (Miniopterus schreibersii) were obtained by Illumina HiSeq 2000.
Project description:Bats harbor high-impact zoonotic viruses in absence of clinical disease, which has been recently associated with unique features of their immune system. They seem to restrict inflammation and possibly limit disease manifestation to a minimum. In-depth characterization of cellular immunity in bats is yet largely missing, and imprinting of age and development on immune cell compartments remains unexplored. We employed single-cell transcriptomics and established immunostaining panels to investigate the immune cell populations peripheral blood for juvenile and adult Egyptian Rousette bats (ERB).
Project description:Unfolded protein accumulation in the lumen of endoplasmic reticulum (ER) induced by cold exposure is termed UPRER. Some mammals hibernate to overcome cold winter. We investigated whether hibernating bats are under UPRER and activate Akt, Nrf2, and NF-κB signaling pathways that are critical for cell survival against cold. Results of Western blotting showed that several UPRER marker proteins such as PERK and ATF4 had a higher abundance in torpid than in active bats. Cellular redistribution of GRP78 and a lower degree of binding between PERK and GRP78 were also seen in torpid bats, suggesting the occurrence of UPRER. Results also showed that torpid bats had a higher amount of p-Akt (Ser473), a higher ratio of p-Akt (Ser473)/Akt, a lower amount of Keap1/Nrf2 and NF-κB (p65)/I-κBα complexes, and a higher degree of NF-κB (p65) nuclear translocation than active bats, indicating simultaneous activation of Akt, Nrf2, and NF-κB during hibernation. Evidence of such activation was not observed in fasted, cold-treated, or normal mice. Using PPI network and IPA analyses, we examined the proteomes of liver and liver mitochondria of bats and found a global metabolic adjustment and survival adaptation in response to UPRER in hibernating bats. Our data provide the first molecular evidence of a complex cross talk involving Akt, Nrf2, and NF-κB via the PERK-EIF2-ATF4 regulatory axis under UPRER in bats to ensure their survival during hibernation.