11 research outputs found

    A comparative study of prenatal development in Miniopterus schreibersii fuliginosus, Hipposideros armiger and H. pratti

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    <p>Abstract</p> <p>Background</p> <p>Bats comprise the second largest order of mammals. However, there are far fewer morphological studies of post-implantation embryonic development than early embryonic development in bats.</p> <p>Results</p> <p>We studied three species of bats (<it>Miniopterus schreibersii fuliginosus, Hipposideros armiger </it>and <it>H. pratti</it>), representing the two suborders Yangochiroptera and Yinpterochiroptera. Using an established embryonic staging system, we identified the embryonic stages for <it>M. schreibersii fuliginosus, H. armiger </it>and <it>H. pratti </it>and described the morphological changes in each species, including the development of the complex and distinctive nose-leaves in <it>H. armiger </it>and <it>H. pratti</it>. Finally, we compared embryonic and fetal morphology of the three species in the present study with five other species for which information is available.</p> <p>Conclusion</p> <p>As a whole, the organogenetic sequence of bat embryos is uniform and the embryos appear homoplastic before Stage 16. Morphological differentiation between species occurs mainly after embryonic Stage 16. Our study provides three new bat species for interspecific comparison of post-implantation embryonic development within the order Chiroptera and detailed data on the development of nose-leaves for bats in the superfamily Rhinolophoidea.</p

    Rhodopsin Molecular Evolution in Mammals Inhabiting Low Light Environments

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    The ecological radiation of mammals to inhabit a variety of light environments is largely attributed to adaptive changes in their visual systems. Visual capabilities are conferred by anatomical features of the eyes as well as the combination and properties of their constituent light sensitive pigments. To test whether evolutionary switches to different niches characterized by dim-light conditions coincided with molecular adaptation of the rod pigment rhodopsin, we sequenced the rhodopsin gene in twenty-two mammals including several bats and subterranean mole-rats. We compared these to thirty-seven published mammal rhodopsin sequences, from species with divergent visual ecologies, including nocturnal, diurnal and aquatic groups. All taxa possessed an intact functional rhodopsin; however, phylogenetic tree reconstruction recovered a gene tree in which rodents were not monophyletic, and also in which echolocating bats formed a monophyletic group. These conflicts with the species tree appear to stem from accelerated evolution in these groups, both of which inhabit low light environments. Selection tests confirmed divergent selection pressures in the clades of subterranean rodents and bats, as well as in marine mammals that live in turbid conditions. We also found evidence of divergent selection pressures among groups of bats with different sensory modalities based on vision and echolocation. Sliding window analyses suggest most changes occur in transmembrane domains, particularly obvious within the pinnipeds; however, we found no obvious pattern between photopic niche and predicted spectral sensitivity based on known critical amino acids. This study indicates that the independent evolution of rhodopsin vision in ecologically specialised groups of mammals has involved molecular evolution at the sequence level, though such changes might not mediate spectral sensitivity directly

    Being a morning man has causal effects on the cerebral cortex: a Mendelian randomization study

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    IntroductionNumerous studies have suggested a connection between circadian rhythm and neurological disorders with cognitive and consciousness impairments in humans, yet little evidence stands for a causal relationship between circadian rhythm and the brain cortex.MethodsThe top 10,000 morningness-related single-nucleotide polymorphisms of the Genome-wide association study (GWAS) summary statistics were used to filter the instrumental variables. GWAS summary statistics from the ENIGMA Consortium were used to assess the causal relationship between morningness and variates like cortical thickness (TH) or surficial area (SA) on the brain cortex. The inverse-variance weighted (IVW) and weighted median (WM) were used as the major estimates whereas MR-Egger, MR Pleiotropy RESidual Sum and Outlier, leave-one-out analysis, and funnel-plot were used for heterogeneity and pleiotropy detecting.ResultsRegionally, morningness decreased SA of the rostral middle frontal gyrus with genomic control (IVW: β = −24.916 mm, 95% CI: −47.342 mm to −2.490 mm, p = 0.029. WM: β = −33.208 mm, 95% CI: −61.933 mm to −4.483 mm, p = 0.023. MR Egger: β &lt; 0) and without genomic control (IVW: β = −24.581 mm, 95% CI: −47.552 mm to −1.609 mm, p = 0.036. WM: β = −32.310 mm, 95% CI: −60.717 mm to −3.902 mm, p = 0.026. MR Egger: β &lt; 0) on a nominal significance, with no heterogeneity or no outliers.Conclusions and implicationsCircadian rhythm causally affects the rostral middle frontal gyrus; this sheds new light on the potential use of MRI in disease diagnosis, revealing the significance of circadian rhythm on the progression of disease, and might also suggest a fresh therapeutic approach for disorders related to the rostral middle frontal gyrus-related

    The complete chloroplast genome sequence of leibnitzia anandria (linnaeus) turczaninow

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    Leibnitzia anandria is a perennial herbaceous plant with medicinal properties, and the entire plant can be used in traditional medicine. Leibnitzia anandria was once classified under the genus Gerbera Cass., but was reclassified under Leibnitzia Cass. recently. In this study, using the GeneLab M sequencing technology of the Genemind platform, we have sequenced, assembled, and analyzed the complete chloroplast genome of Leibnitzia anandria for the first time. The genome is 154168 bp in length, consisting of a large single-copy region(LSC, 80166 bp), a small single-copy region(SSC, 18202 bp), and a pair of inverted repeat sequences(IR, 27900 bp). We have predicted and annotated a total of 133 genes, including 88 protein-coding genes, 37 tRNA-coding genes, and 8 rRNA-coding genes. The results of the phylogenetic analysis indicate that Leibnitzia anandria and Leibnitzia nepalensis, as well as the closely related Gerbera plant, clustered into a separate clade, rather than grouping together with the other plants belonging to the tribe Mutisieae. This study provides new information for the phylogeny research of Leibnitzia anandria, contributing to a better understanding of its taxonomy and evolution

    Digital gene expression tag profiling of bat digits provides robust candidates contributing to wing formation

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    Abstract Background As the only truly flying mammals, bats use their unique wing - consisting of four elongated digits (digits II-V) connected by membranes - to power their flight. In addition to the elongated digits II-V, the forelimb contains one shorter digit (digit I) that is morphologically similar to the hindlimb digits. Here, we capitalized on the morphological variation among the bat forelimb digits to investigate the molecular mechanisms underlying digit elongation and wing formation. Using next generation sequencing technology, we performed digital gene expression tag profiling (DGE-tag profiling) of developing digits in a pooled sample of two Myotis ricketti and validated our sequencing results using real-time quantitative PCR (RT-qPCR) of gene expression in the developing digits of two Hipposideros armiger. Results Among hundreds of genes exhibiting significant differences in expression between the short and long digits, we highlight 14 genes most related to digit elongation. These genes include two Tbx genes (Tbx3 and Tbx15), five BMP pathway genes (Bmp3, RGMB, Smad1, Smad4 and Nog), four Homeobox genes (Hoxd8, Hoxd9, Hoxa1 and Satb1), and three other genes (Twist1, Tmeff2 and Enpp2) related to digit malformations or cell proliferation. In addition, our results suggest that Tbx4 and Pitx2 contribute to the morphological similarity and five genes (Acta1, Tnnc2, Atp2a1, Hrc and Myoz1) contribute to the functional similarity between the thumb and hindlimb digits. Conclusions Results of this study not only implicate many developmental genes as robust candidates underlying digit elongation and wing formation in bats, but also provide a better understanding of the genes involved in autopodial development in general

    The complete chloroplast genome sequence of leibnitzia anandria (linnaeus) turczaninow

    No full text
    Leibnitzia anandria is a perennial herbaceous plant with medicinal properties, and the entire plant can be used in traditional medicine. Leibnitzia anandria was once classified under the genus Gerbera Cass., but was reclassified under Leibnitzia Cass. recently. In this study, using the GeneLab M sequencing technology of the Genemind platform, we have sequenced, assembled, and analyzed the complete chloroplast genome of Leibnitzia anandria for the first time. The genome is 154168 bp in length, consisting of a large single-copy region(LSC, 80166 bp), a small single-copy region(SSC, 18202 bp), and a pair of inverted repeat sequences(IR, 27900 bp). We have predicted and annotated a total of 133 genes, including 88 protein-coding genes, 37 tRNA-coding genes, and 8 rRNA-coding genes. The results of the phylogenetic analysis indicate that Leibnitzia anandria and Leibnitzia nepalensis, as well as the closely related Gerbera plant, clustered into a separate clade, rather than grouping together with the other plants belonging to the tribe Mutisieae. This study provides new information for the phylogeny research of Leibnitzia anandria, contributing to a better understanding of its taxonomy and evolution.</p

    Table_1_Being a morning man has causal effects on the cerebral cortex: a Mendelian randomization study.XLSX

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    IntroductionNumerous studies have suggested a connection between circadian rhythm and neurological disorders with cognitive and consciousness impairments in humans, yet little evidence stands for a causal relationship between circadian rhythm and the brain cortex.MethodsThe top 10,000 morningness-related single-nucleotide polymorphisms of the Genome-wide association study (GWAS) summary statistics were used to filter the instrumental variables. GWAS summary statistics from the ENIGMA Consortium were used to assess the causal relationship between morningness and variates like cortical thickness (TH) or surficial area (SA) on the brain cortex. The inverse-variance weighted (IVW) and weighted median (WM) were used as the major estimates whereas MR-Egger, MR Pleiotropy RESidual Sum and Outlier, leave-one-out analysis, and funnel-plot were used for heterogeneity and pleiotropy detecting.ResultsRegionally, morningness decreased SA of the rostral middle frontal gyrus with genomic control (IVW: β = −24.916 mm, 95% CI: −47.342 mm to −2.490 mm, p = 0.029. WM: β = −33.208 mm, 95% CI: −61.933 mm to −4.483 mm, p = 0.023. MR Egger: β Conclusions and implicationsCircadian rhythm causally affects the rostral middle frontal gyrus; this sheds new light on the potential use of MRI in disease diagnosis, revealing the significance of circadian rhythm on the progression of disease, and might also suggest a fresh therapeutic approach for disorders related to the rostral middle frontal gyrus-related.</p
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