Search for Chelyabinsk Meteorite Fragments in Chebarkul Lake Bottom (GPR and Magnetic Data), Journal of Telecommunications and Information Technology, 2017, nr 3

The paper summarizes experimental efforts of the Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (IZMIRAN) undertaken in search of the biggest part of Chelyabinsk meteorite in the bottom of lake Chebarkul, South Ural, Russia, and to estimate the ecological effects of its subsequent excavation

Additional file 1: Figure S1. of The exon junction complex factor Y14 is dynamic in the nucleus of the beetle Tribolium castaneum during late oogenesis

Protein alignment of Tribolium castaneum Y14 (XP_967777), Drosophila melanogaster Y14 (NP_610454) and Homo sapiens Y14 (NP_005096). Y14 RNA binding/recognition domain (RRM/RBM8) indicated with grey. Identical amino acids highlighted in black, similar in grey. Alignment and visualization performed with Geneious 6 Software (TIFF 181 kb

The exon junction complex factor Y14 is dynamic in the nucleus of the beetle Tribolium castaneum during late oogenesis

Abstract Background The oocyte chromosomes of the red flour beetle, Tribolium castaneum, are gathered into a knot, forming a karyosphere at the diplotene stage of meiotic prophase. Chromatin rearrangement, which is a characteristic feature of oocyte maturation, is well documented. The T. castaneum karyosphere is surrounded by a complex extrachromosomal structure termed the karyosphere capsule. The capsule contains the vast majority of oocyte RNA. We have previously shown using a BrUTP assay that oocyte chromosomes in T. castaneum maintain residual transcription up to the very end of oocyte maturation. Karyosphere transcription requires evidently not only transcription factors but also mRNA processing factors, including the components of the exon junction complex with its core component, the splicing factor Y14. We employed a gene engineering approach with injection of mRNA derived from the Myc-tagged Y14 plasmid-based construct in order to monitor the newly synthesized fusion protein in the oocyte nuclei. Results Our preliminary data have been presented as a brief correspondence elsewhere. Here, we provide a full-length article including immunoelectron-microscopy localization data on Y14–Myc distribution in the nucleus of previtellogenic and vitellogenic oocytes. The injections of the fusion protein Y14–Myc mRNA into the oocytes showed a dynamic pattern of the protein distribution. At the previtellogenic stage, there are two main locations for the protein: SC35 domains (the analogues of interchromatin granule clusters or nuclear speckles) and the karyosphere capsule. At the vitellogenic stage, SC35 domains were devoid of labels, and Y14–Myc was found in the perichromatin region of the karyosphere, presumably at the places of residual transcription. We show that karyosphere formation is accompanied by the movement of a nuclear protein while the residual transcription occurs during genome inactivation. Conclusions Our data indicate that the karyosphere capsule, being a destination site for a protein involved in mRNA splicing and export, is not only a specializes part of nuclear matrix separating the karyosphere from the products of chromosome activity, as believed previously, but represents a special nuclear compartment involved in the processes of gene expression in the case the karyosphere retains residual transcription activity

Additional file 2: Figure S2. of The exon junction complex factor Y14 is dynamic in the nucleus of the beetle Tribolium castaneum during late oogenesis

Differences between Y14 splicing systems in human and T. castaneum cells. A, The genome sequence of T. castaneum Y14. B, Normally spliced Y14 mRNA of T. castaneum. C, Abnormal splicing of T. castaneum Y14 mRNA in human HEK293 cells (TIFF 204 kb) Green, exons; blue, introns