5 research outputs found
A new species of Carpenter Moths (Lepidoptera, Cossidae) from Tarbagatai (NE Kazakhstan) and Altai (SW Siberia, Russia) Mountains
Yakovlev, Roman V., Shapoval, Nazar A., Ivonin, Vadim V., Knyazev, Svyatoslav A., Kuftina, Galina N., Masharskiy, Alexey E. (2020): A new species of Carpenter Moths (Lepidoptera, Cossidae) from Tarbagatai (NE Kazakhstan) and Altai (SW Siberia, Russia) Mountains. Zootaxa 4896 (1): 85-95, DOI: https://doi.org/10.11646/zootaxa.4896.1.
Data on RNA-seq analysis of the oviducts of five closely related species genus <i>Littorina</i> (Mollusca, Caenogastropoda): <i>L. saxatilis, L. arcana, L. compressa, L. obtusata, L. fabalis</i>.
In the evolution of invertebrates, the transition from egg-layers to brooders occurred many times. However, the molecular mechanisms underlying this transition are still not well understood. Recently diverged species genus Littorina (Mollusca, Gastropoda, Caenogastropoda, Littorinimorpha): Littorina saxatilis, L. arcana, L. compressa, L. obtusata and L. fabalis might be a fruitful model for elucidation of these mechanisms. All five species sympatrically inhabit an intertidal zone. Only L. saxatilis is ovoviviparous while the other four species form clutches. Although in L. saxatilis jelly gland of the pallial oviduct function as a brood pouch, it is not deeply modified at the morphological level in comparison to egg-laying relatives. Comparative analysis of transcriptomic profiles of the pallial oviducts of these closely related species might help to uncover the molecular mechanisms of the egg-laying to brooding transition. Unraveling of the mechanisms underlying this transition in L. saxatilis is important not only in aspects of reproduction biology and strategy, but also in a broader view as an example of relatively fast evolutionary transformations. We generated an RNA-seq dataset (224Â 104Â 446 clean reads) for oviducts of five species genus Littorina. Libraries of all five species were sequenced using Illumina HiSeq 2500; additional reads for L. arcana were obtained using Illumina NovaSeq 6000. Transcriptomic profiles were analyzed in pooled samples (of three individuals) with two biological replicates for each species (each biological replicate was prepared and sequenced as a separate library). The transcriptome was assembled de novo and annotated with five assembles corresponding to each species. The raw data were uploaded to the SRA database, the BioProject IDs are PRJNA662103 ("obtusata" group) and PRJNA707549 ("saxatilis" group)
Species-Specific Proteins in the Oviducts of Snail Sibling Species: Proteotranscriptomic Study of Littorina fabalis and L. obtusata
SIMPLE SUMMARY: Genitalia and reproduction-associated proteins are often species-specific and might evolve rapidly. The situation in which the morphology of the reproductive system is the only difference between two or several closely related species has been reported on multiple occasions. Nevertheless, the reasons for such rapid divergence of the reproductive system is still poorly investigated. To shed some light on the issue, we performed a transcriptomic and proteomic comparison of pallial oviducts from the two sibling species of gastropods Littorina obtusata and L. fabalis. The main identified differences were associated with three functional groups of genes: transposable elements, which enhance genome variation and promote the evolution of new genes, receptor proteins potentially involved in friend or foe recognition, and various enzymes. We hypothesize that these functional groups reflect both the mechanism (transposable elements) and the directions (friend or foe recognition and reproductive physiology) of the rapid evolution of the reproductive system. ABSTRACT: Genus Littorina subgenus Neritrema (Mollusca, Caenogastropoda) includes the “obtusata” group of closely related species (Littorina obtusata and L. fabalis). The anatomy of the adult reproductive system (pallial oviduct) is the only reliable feature used for species identification in females of these species. Reproductive system anatomy and reproduction-associated proteins often diverge between sibling species. Despite being of high evolutionary interest, the molecular basis of this divergence remains poorly understood. We performed proteotranscriptomic comparison of oviducts of L. obtusata and L. fabalis by RNA-seq on Illumina HiSeq 2500 and two-dimensional protein electrophoresis (2D DIGE) with MS/MS identification of the species-specific proteins. The interspecies differences in the oviduct were associated with (1) metabolic proteins reflecting overall physiological differences between L. obtusata and L. fabalis, (2) receptor proteins, and (3) transcripts related to transposable elements (TEs). Various receptors identified may recognize a wide variety of ligands from pathogen-associated molecular patterns to specific carbohydrates on the sperm surface. Therefore, these may participate in immune defense as well as in sperm storage and regulation. Species-specificity of multiple TE sequences (coding for reverse transcriptase and ribonuclease H) may indicate the important role of these genomic elements in the Littorina species divergence, which has not been reported previously
Modulation of Notch Signaling at Early Stages of Differentiation of Human Induced Pluripotent Stem Cells to Dopaminergic Neurons
Elaboration of protocols for differentiation of human pluripotent stem cells to dopamine neurons is an important issue for development of cell replacement therapy for Parkinson’s disease. A number of protocols have been already developed; however, their efficiency and specificity still can be improved. Investigating the role of signaling cascades, important for neurogenesis, can help to solve this problem and to provide a deeper understanding of their role in neuronal development. Notch signaling plays an essential role in development and maintenance of the central nervous system after birth. In our study, we analyzed the effect of Notch activation and inhibition at the early stages of differentiation of human induced pluripotent stem cells to dopaminergic neurons. We found that, during the first seven days of differentiation, the cells were not sensitive to the Notch inhibition. On the contrary, activation of Notch signaling during the same time period led to significant changes and was associated with an increase in expression of genes, specific for caudal parts of the brain, a decrease of expression of genes, specific for forebrain, as well as a decrease of expression of genes, important for the formation of axons and dendrites and microtubule stabilizing proteins
A woolly mammoth (Mammuthus primigenius) carcass from Maly Lyakhovsky Island (New Siberian Islands, Russian Federation)
A partial carcass of an adult woolly mammoth (Mammuthus primigenius) found in 2012 on Maly Lyakhovsky Island presents a new opportunity to retrieve associated anatomical, morphological, and life history data on this important component of Pleistocene biotas. In addition, we address hematological, histological, and microbiological issues that relate directly to quality of preservation. Recovered by staff from North-Eastern Federal University in Yakutsk, this individual is a relatively old female preserving soft tissue of the anteroventral portion of the head, most of both fore-quarters, and the ventral aspect of much of the rest of the body. Both tusks were recovered and subjected to computed tomographic analysis in which annual dentin increments were revealed as cycles of variation in X-ray attenuation. Measurements of annual increment areas (in longitudinal section) display a pulsed pattern of tusk growth showing cycles of growth rate variation over periods of 3-5 years. These intervals are interpreted as calving cycles reflecting regular shifts in calcium and phosphate demand for tusk growth vs. fetal ossification and lactation. Brown liquid associated with the frozen carcass turned out to include remains of hemolyzed blood, and blood samples examined microscopically included white blood cells with preserved nuclei. Muscle tissue from the trunk was unusually well preserved, even at the histological level. Intestinal contents and tissue samples were investigated microbiologically, and several strains of lacticacid bacteria (e.g., Enterococcus faecium, Enterococcus hirae) that are widely distributed as commensal organisms in the intestines of herbivores were isolated. (C) 2017 Elsevier Ltd and INQUA. All rights reserved