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991.
Agnieszka Gornicka Piotr Bragoszewski Piotr Chroscicki Lena-Sophie Wenz Christian Schulz Peter Rehling Agnieszka Chacinska 《Molecular biology of the cell》2014,25(25):3999-4009
Mitochondrial proteins are synthesized on cytosolic ribosomes and imported into mitochondria with the help of protein translocases. For the majority of precursor proteins, the role of the translocase of the outer membrane (TOM) and mechanisms of their transport across the outer mitochondrial membrane are well recognized. However, little is known about the mode of membrane translocation for proteins that are targeted to the intermembrane space via the redox-driven mitochondrial intermembrane space import and assembly (MIA) pathway. On the basis of the results obtained from an in organello competition import assay, we hypothesized that MIA-dependent precursor proteins use an alternative pathway to cross the outer mitochondrial membrane. Here we demonstrate that this alternative pathway involves the protein channel formed by Tom40. We sought a translocation intermediate by expressing tagged versions of MIA-dependent proteins in vivo. We identified a transient interaction between our model substrates and Tom40. Of interest, outer membrane translocation did not directly involve other core components of the TOM complex, including Tom22. Thus MIA-dependent proteins take another route across the outer mitochondrial membrane that involves Tom40 in a form that is different from the canonical TOM complex. 相似文献
992.
Monika Marędziak Krzysztof Marycz Agnieszka Śmieszek Daniel Lewandowski Nezir Yaşar Toker 《In vitro cellular & developmental biology. Animal》2014,50(6):562-571
The aim of this study was to evaluate the proliferation rate and morphological changes of adipose-derived mesenchymal stem cells of canine and equine origin (Eq- and CaAdMSC). Investigated cells were exposed to a static magnetic field (MF) with the intensity of 0.5 T. Proliferation activity of cells was determined with the Alamar Blue assay. Obtained results, normalized in respect to the control culture, showed that EqAdMSC exposed to MF maintained a high proliferation status, whereas proliferation activity of CaAdMSC cultured in the presence of MF was decreased. Estimations of population doubling time (PDT) also revealed that EqAdMSCs exposed to static MF achieved a twofold increase in the total number of cells in a shorter amount of time than the control culture. The PDT value obtained for investigated CaAdMSCs indicated that MF exposure resulted in the prolongation of population doubling time. Morphology of cells and cellular composition was investigated using a light inverted microscope and a fluorescent microscope. A scanning electron microscope was used for microvesicles (MVs) imaging. Obtained results showed that both cell types maintained fibroblastic morphology and did not reveal signs of apoptosis or necrosis. However, the MF had an influence on the MVs secretion. While EqAdMSCs propagated in the presence of MF were characterized by the abundant MVs presence, CaAdMSCs revealed poor secretory activity. The approach presented provides complex analysis, which enables one to determine changes in equine and canine cytophysiology. 相似文献
993.
Agnieszka Braszewska-Zalewska Marta Tylikowska Jolanta Kwasniewska Joanna Szymanowska-Pulka 《Journal of applied genetics》2014,55(4):449-456
In addition to their normal developmental processes, plants have evolved complex genetic and epigenetic regulatory mechanisms to cope with various environmental stresses. It has been shown that both DNA methylation and histone modifications are involved in DNA damage response to various types of stresses. In this study, we focused on the involvement of two mutagenic agents, chemical (maleic acid hydrazide; MH) and physical (gamma rays), on the global epigenetic modifications of chromatin in barley. Our results indicate that both mutagens strongly influence the level of histone methylation and acetylation. Moreover, we found that gamma irradiation, in contrast to MH, has a more robust influence on the DNA methylation level. This is the first study that brings together mutagenic treatment along with its impact at the level of epigenetic modifications examined using the immunohistochemical method. 相似文献
994.
Maciej Walczak Agnieszka Richert Aleksandra Burkowska-But 《Journal of industrial microbiology & biotechnology》2014,41(11):1719-1724
The present study was aimed at investigating bactericidal properties of polylactide (PLA) films containing three different polyhexamethylene guanidine hydrochloride (PHMG) derivatives and effect of the derivatives on extracellular hydrolytic enzymes and intracellular dehydrogenases. All PHMG derivatives had a slightly stronger bactericidal effect on Staphylococcus aureus than on E. coli but only PHMG granular polyethylene wax (at the concentration of at least 0.6 %) has a bactericidal effect. PHMG derivatives introduced into PLA affected the activity of microbial hydrolases to a small extent. This means that the introduction of PHMG derivatives into PLA will not reduce its enzymatic biodegradation significantly. On the other hand, PHMG derivatives introduced into PLA strongly affected dehydrogenases activity in S. aureus than in E. coli. 相似文献
995.
Sarah Voisin Pawel Cieszczyk Vladimir P Pushkarev Dmitry A Dyatlov Boris F Vashlyayev Vladimir A Shumaylov Agnieszka Maciejewska-Karlowska Marek Sawczuk Lidia Skuza Zbigniew Jastrzebski David J Bishop Nir Eynon 《BMC genomics》2014,15(1)
Background
The endothelial PAS domain protein 1 (EPAS1) activates genes that are involved in erythropoiesis and angiogenesis, thus favoring a better delivery of oxygen to the tissues and is a plausible candidate to influence athletic performance. Using innovative statistical methods we compared genotype distributions and interactions of EPAS1 SNPs rs1867785, rs11689011, rs895436, rs4035887 and rs1867782 between sprint/power athletes (n = 338), endurance athletes (n = 254), and controls (603) in Polish and Russian samples. We also examined the association between these SNPs and the athletes’ competition level (‘elite’ and ‘sub-elite’ level). Genotyping was performed by either Real-Time PCR or by Single-Base Extension (SBE) method.Results
In the pooled cohort of Polish and Russian athletes, 1) rs1867785 was associated with sprint/power athletic status; the AA genotype in rs1867785 was underrepresented in the sprint/power athletes, 2) rs11689011 was also associated with sprint/power athletic status; the TT genotype in rs11689011 was underrepresented sprint/power athletes, and 3) the interaction between rs1867785, rs11689011, and rs4035887 was associated with sprint/power athletic performance; the combinations of the AA genotype in rs4035887 with either the AG or GG genotypes in rs1867785, or with the CT or CC genotypes in rs11689011, were underrepresented in two cohorts of sprint/power athletes.Conclusions
Based on the unique statistical model rs1867785/rs11689011 are strong predictors of sprint/power athletic status, and the interaction between rs1867785, rs11689011, and rs4035887 might contribute to success in sprint/power athletic performance.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-382) contains supplementary material, which is available to authorized users. 相似文献996.
Aleksandra Simiczyjew Antonina Joanna Mazur Agnieszka Popow-Woźniak Maria Malicka-Błaszkiewicz Dorota Nowak 《Histochemistry and cell biology》2014,142(3):307-322
Actins are eukaryotic proteins, which are involved in diverse cellular functions including muscle contraction, cell motility, adhesion and maintenance of cell shape. Cytoplasmic actin isoforms β and γ are ubiquitously expressed and essential for cell functioning. However, their unique contributions are not very well understood. The aim of this study was to determine the effect of β- and γ-actin overexpression on the migration capacity and actin cytoskeleton organization of human colon adenocarcinoma BE cells. In cells overexpressing β- or γ-actin, distinct cytoskeletal actin rearrangements were observed under the laser scanning confocal microscope. Overexpressed actins localized at the submembranous region of the cell body, especially near to the leading edge and on the tips of pseudopodia. The cells transfected with plasmids containing cDNA for β- or γ-actin were characterized by increased migration and invasion capacities. However, the migration velocity was statistically significantly higher only in the case of γ-actin overexpressing cells. In conclusion, the increased level of β- or γ-actin leads to actin cytoskeletal remodeling followed by an increase in migration and invasion capacities of human colon BE cells. These data suggest that expression of both actin isoforms has an impact on cancer cell motility, with the subtle predominance of γ-actin, and may influence invasiveness of human colon cancer. 相似文献
997.
Marta Pilarczyk Lukasz Mateuszuk Anna Rygula Mariusz Kepczynski Stefan Chlopicki Malgorzata Baranska Agnieszka Kaczor 《PloS one》2014,9(8)
Lipid rafts (LRs) are dynamic, sterol- and sphingolipid-enriched nanodomains involved in the regulation of cellular functions and signal transduction, that upon stimuli, via (e.g. association of raft proteins and lipids), may cluster into domains of submicron or micron scale. Up to date, however, lipid raft clusters were observed only under artificially promoted conditions and their formation in vivo has not been confirmed. Using non-destructive approach involving Raman and Atomic Force Microscopy imaging we demonstrated the presence of clustered lipid rafts in endothelium of the aorta of the db/db mice that represent a reliable murine model of type 2 diabetes. The raft clusters in the aorta of diabetic mice were shown to occupy a considerably larger (about 10-fold) area of endothelial cells surface as compared to the control. Observation of pathology-promoted LRs confirms that the cellular increase of lipid content results in clustering of LRs. Clustering of LRs leads to the formation of assemblies with diameters up to 3 micrometers and increased lipid character. This massive clustering of lipid rafts in diabetes may trigger a signaling cascade leading to vascular inflammation. 相似文献
998.
Magdalena Winiarska Kamil Bojarczuk Beata Pyrzynska Jacek Bil Marta Siernicka Michal Dwojak Malgorzata Bobrowicz Nina Miazek Piotr Zapala Agnieszka Zagozdzon Magdalena Krol Aleksandra Syta Paulina Podszywalow-Bartnicka Zofia Pilch Anna Dabrowska-Iwanicka Przemyslaw Juszczynski Dimitar G Efremov Mikolaj Slabicki Thorsten Zenz Aude Le Roy Daniel Olive Tomasz P Rygiel Jeanette HW Leusen Jakub Golab 《MABS-AUSTIN》2014,6(5):1300-1313
999.
Lionel Moulin Agnieszka Klonowska Bournaud Caroline Kristina Booth Jan A.C. Vriezen Rémy Melkonian Euan K. James J. Peter W. Young Gilles Bena Loren Hauser Miriam Land Nikos Kyrpides David Bruce Patrick Chain Alex Copeland Sam Pitluck Tanja Woyke Michelle Lizotte-Waniewski Jim Bristow Margaret Riley 《Standards in genomic sciences》2014,9(3):763-774
Burkholderia phymatum is a soil bacterium able to develop a nitrogen-fixing symbiosis with species of the legume genus Mimosa, and is frequently found associated specifically with Mimosa pudica. The type strain of the species, STM 815T, was isolated from a root nodule in French Guiana in 2000. The strain is an aerobic, motile, non-spore forming, Gram-negative rod, and is a highly competitive strain for nodulation compared to other Mimosa symbionts, as it also nodulates a broad range of other legume genera and species. The 8,676,562 bp genome is composed of two chromosomes (3,479,187 and 2,697,374 bp), a megaplasmid (1,904,893 bp) and a plasmid hosting the symbiotic functions (595,108 bp). 相似文献
1000.
Agnieszka M. Szemiel Anna-Bella Failloux Richard M. Elliott 《PLoS neglected tropical diseases》2012,6(9)