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91.
Płaczkiewicz Jagoda Chmiel Paulina Malinowska Ewelina Bącal Pawel Kwiatek Agnieszka 《Journal of microbiology (Seoul, Korea)》2020,58(5):405-414
Journal of Microbiology - Neisseria gonorrhoeae, an obligatory human pathogen causes the sexually transmitted disease gonorrhea, which remains a global health problem. N. gonorrhoeae primarily... 相似文献
92.
Wetlands Ecology and Management - Currently, due to prolonged soil drought, dehydrated peat soils are particularly exposed to subsidence and, as a consequence, even to disappearance from the... 相似文献
93.
Chiasmata resulting from interhomolog recombination are critical for proper chromosome segregation at meiotic metaphase I, thus preventing aneuploidy and consequent deleterious effects. Recombination in meiosis is driven by programmed induction of double strand breaks (DSBs), and the repair of these breaks occurs primarily by recombination between homologous chromosomes, not sister chromatids. Almost nothing is known about the basis for recombination partner choice in mammals. We addressed this problem using a genetic approach. Since meiotic recombination is coupled with synaptonemal complex (SC) morphogenesis, we explored the role of axial elements--precursors to the lateral element in the mature SC--in recombination partner choice, DSB repair pathways, and checkpoint control. Female mice lacking the SC axial element protein SYCP3 produce viable, but often aneuploid, oocytes. We describe genetic studies indicating that while DSB-containing Sycp3-/- oocytes can be eliminated efficiently, those that survive have completed repair before the execution of an intact DNA damage checkpoint. We find that the requirement for DMC1 and TRIP13, proteins normally essential for recombination repair of meiotic DSBs, is substantially bypassed in Sycp3 and Sycp2 mutants. This bypass requires RAD54, a functionally conserved protein that promotes intersister recombination in yeast meiosis and mammalian mitotic cells. Immunocytological and genetic studies indicated that the bypass in Sycp3-/- Dmc1-/- oocytes was linked to increased DSB repair. These experiments lead us to hypothesize that axial elements mediate the activities of recombination proteins to favor interhomolog, rather than intersister recombinational repair of genetically programmed DSBs in mice. The elimination of this activity in SYCP3- or SYCP2-deficient oocytes may underlie the aneuploidy in derivative mouse embryos and spontaneous abortions in women. 相似文献
94.
Polysomaty was studied using flow cytometry in different organs of diploid, triploid and tetraploid sugar-beet (Beta vulgaris L.) plants, in the first (at harvest) and the second (at the height of the blooming period) year of development. Of the organs/parts
of organs of the vegetative plant that developed during the first year, only the leaf lamina did not contain endopolyploid
cells; in all others, one to three endocycles had occurred. The second-year seed-crop plant was also highly polysomatic; even
in reproductive organs such as the flower and pericarp the endopolyploid cells were present (up to 8C and 32C, respectively).
At this stage of development no endocycles occurred in the leaf lamina, flower bract, and inflorescence bract. The parts of
the plant with no endopolyploid cells are recommended for ploidy estimation, and as a material suitable for micropropagation
and genetic manipulations. Endoreduplication, up to 32C (64Cx), was organ-specific and correlated negatively with plant ploidy.
The highest mean C-value, over 7, was in the diploid, in the basal part of the oldest leaf petiole in the first-year plant,
and in the storage parenchyma of the root in the second-year seed-crop plant. The results confirm that higher endopolyploidy
occurs in plants with a smaller 2C DNA amount than in those with a larger one. The significance of endopolyploidization in
development of sugar-beet plant organs is discussed. 相似文献
95.
Lackmann Alec R. Bielak-Lackmann Ewelina S. Jacobson Reed I. Butler Malcolm G. Clark Mark E. 《Environmental Biology of Fishes》2022,105(8):1051-1064
Environmental Biology of Fishes - The carpsuckers, which include Quillback Carpiodes cyprinus, river carpsucker Carpiodes carpio, and highfin carpsucker Carpiodes velifer, are ictiobine catostomids... 相似文献
96.
Eckert Ewelina Zambrowicz Aleksandra Bobak Łukasz Zabłocka Agnieszka Chrzanowska Józefa Trziszka Tadeusz 《International journal of peptide research and therapeutics》2019,25(2):669-680
International Journal of Peptide Research and Therapeutics - Biologically active peptides derived from food proteins have been increasingly popular due to their therapeutic properties. This paper... 相似文献
97.
Ewelina Szafraniec Edyta Kus Adrianna Wislocka Bozena Kukla Ewa Sierka Valrie Untereiner Ganesh D. Sockalingum Stefan Chlopicki Malgorzata Baranska 《Journal of biophotonics》2019,12(4)
Liver sinusoidal endothelial cells (LSECs), a type of endothelial cells with unique morphology and function, play an important role in the liver hemostasis, and LSECs dysfunction is involved in the development of nonalcoholic fatty liver disease (NAFLD). Here, we employed Raman imaging and chemometric data analysis in order to characterize the presence of lipid droplets (LDs) and their lipid content in primary murine LSECs, in comparison with hepatocytes, isolated from mice on high‐fat diet. On NAFLD development, LDs content in LSECs changed toward more unsaturated lipids, and this response was associated with an increased expression of stearylo‐CoA desaturase‐1. To the best of our knowledge, this is a first report characterizing LDs in LSECs, where their chemical composition is analyzed along the progression of NAFLD at the level of single LD using Raman imaging. 相似文献
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CRISPR/Cas9 system of RNA-guided genome editing is revolutionizing genetics research in a wide spectrum of organisms. Even for the laboratory mouse, a model that has thrived under the benefits of embryonic stem (ES) cell knockout capabilities for nearly three decades, CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 technology enables one to manipulate the genome with unprecedented simplicity and speed. It allows generation of null, conditional, precisely mutated, reporter, or tagged alleles in mice. Moreover, it holds promise for other applications beyond genome editing. The crux of this system is the efficient and targeted introduction of DNA breaks that are repaired by any of several pathways in a predictable but not entirely controllable manner. Thus, further optimizations and improvements are being developed. Here, we summarize current applications and provide a practical guide to use the CRISPR/Cas9 system for mouse mutagenesis, based on published reports and our own experiences. We discuss critical points and suggest technical improvements to increase efficiency of RNA-guided genome editing in mouse embryos and address practical problems such as mosaicism in founders, which complicates genotyping and phenotyping. We describe a next-generation sequencing strategy for simultaneous characterization of on- and off-target editing in mice derived from multiple CRISPR experiments. Additionally, we report evidence that elevated frequency of precise, homology-directed editing can be achieved by transient inhibition of the Ligase IV-dependent nonhomologous end-joining pathway in one-celled mouse embryos. 相似文献
100.