The Mason-Pfizer monkey virus is a type D retrovirus, which assembles its immature particles in the cytoplasm prior to their transport to the host cell membrane. The association with the membrane is mediated by the N-terminally myristoylated matrix protein. To reveal the role of particular residues which are involved in the capsid-membrane interaction, covalent labelling of arginine, lysine and tyrosine residues of the Mason-Pfizer monkey virus matrix protein bound to artificial liposomes containing 95% of phosphatidylcholine and 5% phosphatidylinositol-(4,5)-bisphosphate (PI(4,5)P2 ) was performed. The experimental results were interpreted by multiscale molecular dynamics simulations. The application of these two complementary approaches helped us to reveal that matrix protein specifically recognizes the PI(4,5)P2 molecule by the residues K20, K25, K27, K74, and Y28, while the residues K92 and K93 stabilizes the matrix protein orientation on the membrane by the interaction with another PI(4,5)P2 molecule. Residues K33, K39, K54, Y66, Y67, and K87 appear to be involved in the matrix protein oligomerization. All arginine residues remained accessible during the interaction with liposomes which indicates that they neither contribute to the interaction with membrane nor are involved in protein oligomerization. Proteins 2016; 84:1717-1727. © 2016 Wiley Periodicals, Inc.
- MeSH
- arginin chemie MeSH
- barvení a značení MeSH
- fosfatidylcholiny chemie MeSH
- fosfatidylinositol-4,5-difosfát chemie MeSH
- liposomy chemie MeSH
- lysin chemie MeSH
- Masonův-Pfizerův opičí virus chemie MeSH
- peptidy chemie MeSH
- proteiny virové matrix chemie MeSH
- sekvence aminokyselin MeSH
- simulace molekulární dynamiky MeSH
- tyrosin chemie MeSH
- vazba proteinů MeSH
- Publikační typ
- časopisecké články MeSH
Zn-(0-1.6)Mg (in wt.%) alloys were prepared by hot extrusion at 300 °C. The structure, mechanical properties and in vitro biocompatibility of the alloys were investigated. The hot-extruded magnesium-based WE43 alloy was used as a control. Mechanical properties were evaluated by hardness, compressive and tensile testing. The cytotoxicity, genotoxicity (comet assay) and mutagenicity (Ames test) of the alloy extracts and ZnCl2 solutions were evaluated with the use of murine fibroblasts L929 and human osteosarcoma cell line U-2 OS. The microstructure of the Zn alloys consisted of recrystallized Zn grains of 12 μm in size and fine Mg2Zn11 particles arranged parallel to the hot extrusion direction. Mechanical tests revealed that the hardness and strength increased with increasing Mg concentration. The Zn-0.8 Mg alloys showed the best combination of tensile mechanical properties (tensile yield strength of 203 MPa, ultimate tensile strength of 301 MPa and elongation of 15%). At higher Mg concentrations the plasticity of Zn-Mg alloys was deteriorated. Cytotoxicity tests with alloy extracts and ZnCl2 solutions proved the maximum safe Zn(2+) concentrations of 120 μM and 80 μM for the U-2 OS and L929 cell lines, respectively. Ames test with extracts of alloys indicated that the extracts were not mutagenic. The comet assay demonstrated that 1-day extracts of alloys were not genotoxic for U-2 OS and L929 cell lines after 1-day incubation.
- MeSH
- biokompatibilní materiály chemie toxicita MeSH
- hořčík chemie toxicita MeSH
- kultivované buňky MeSH
- lidé MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- poškození DNA účinky léků MeSH
- slitiny chemie toxicita MeSH
- viabilita buněk účinky léků MeSH
- zinek chemie toxicita MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Phosphatase and tensin homolog (PTEN) is a protein that acts as a tumor suppressor by dephosphorylating the lipid second messenger phosphatidylinositol 3,4,5-trisphosphate. Loss of PTEN function has been implicated in the pathogenesis of a number of different tumors, particularly endometrial carcinoma (ECa). ECa is the most common neoplasia of the female genital tract. Our study evaluates an association between the morphological appearance of endometrial hyperplasia and endometrial carcinoma and the degree of PTEN alterations. A total of 45 endometrial biopsies from Slovak women were included in present study. Formalin-fixed and paraffin-embedded tissue samples with simple hyperplasia (3), complex hyperplasia (5), atypical complex hyperplasia (7), endometrioid carcinomas G1 (20) and G3 (5), and serous carcinoma (5) were evaluated for the presence of mutations in coding regions of PTEN gene, the most frequently mutated tumor suppressor gene in endometrial carcinoma. 75% of the detected mutations were clustered in exons 5 and 8. Out of the 39 mutations detected in 24 cases, 20 were frameshifts and 19 were nonsense, missense, or silent mutations. Some specimens harboured more than one mutation. The results of current study on Slovak women were compared to a previous study performed on Polish population. The two sets of results were similar.
- MeSH
- fosfohydroláza PTEN genetika MeSH
- hyperplazie endometria genetika MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- mutace genetika MeSH
- mutační analýza DNA MeSH
- mutační rychlost MeSH
- nádory endometria genetika MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA * MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Slovenská republika MeSH
A novel pentamethinium salt was synthesized with an unforeseen expanded conjugated quinoxaline unit directly incorporated into a pentamethinium chain. The compound exhibited high fluorescence intensity, selective mitochondrial localization, high cytotoxicity, and selectivity toward malignant cell lines, and resulted in remarkable in vivo suppression of tumor growth in mice.
- MeSH
- antitumorózní látky chemie terapeutické užití MeSH
- chinoxaliny chemie terapeutické užití MeSH
- cyklizace MeSH
- hexamethonium chemie terapeutické užití MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádory farmakoterapie patologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
As-cast Mg-Sn, Mg-Ga and Mg-In alloys containing 1-7 wt.% of alloying elements were studied in this work. Structural and chemical analysis of the alloys was performed by using light and scanning electron microscopy, energy dispersive spectrometry, x-ray diffraction, x-ray photoelectron spectroscopy and glow discharge spectrometry. Mechanical properties were determined by Vickers hardness measurements and tensile testing. Corrosion behavior in a simulated physiological solution (9 g/l NaCl) was studied by immersion tests and potentiodynamic measurements. The cytotoxicity effect of the alloys on human osteosarcoma cells (U-2 OS) was determined by an indirect contact assay. Structural investigation revealed the dendritic morphology of the as-cast alloys with the presence of secondary eutectic phases in the Mg-Sn and Mg-Ga alloys. All the alloying elements showed hardening and strengthening effects on magnesium. This effect was the most pronounced in the case of Ga. All the alloying elements at low concentrations of approximately 1 wt.% were also shown to positively affect the corrosion resistance of Mg. But at higher concentrations of Ga and Sn the corrosion resistance worsened due to galvanic effects of secondary phases. Cytotoxicity tests indicated that Ga had the lowest toxicity, followed by Sn. The most severe toxicity was observed in the case of In.
- MeSH
- biokompatibilní materiály chemie farmakologie MeSH
- buněčná smrt účinky léků MeSH
- fotoelektronová spektroskopie MeSH
- koroze MeSH
- kovy farmakologie MeSH
- lidé MeSH
- mechanické jevy účinky léků MeSH
- mikroskopie elektronová rastrovací MeSH
- nádorové buněčné linie MeSH
- pevnost v tahu účinky léků MeSH
- potenciometrie MeSH
- slitiny chemie farmakologie MeSH
- testování materiálů * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Assembly of immature retroviral particles is a complex process involving interactions of several specific domains of the Gag polyprotein localized mainly within capsid protein (CA), spacer peptide (SP), and nucleocapsid protein (NC). In the present work we focus on the contribution of NC to the oligomerization of CA leading to assembly of Mason-Pfizer monkey virus (M-PMV) and HIV-1. Analyzing in vitro assembly of substitution and deletion mutants of DeltaProCANC, we identified a "spacer-like" sequence (NC(15)) at the M-PMV NC N terminus. This NC(15) domain is indispensable for the assembly and cannot be replaced with oligomerization domains of GCN4 or CREB proteins. Although the M-PMV NC(15) occupies a position analogous to that of the HIV-1 spacer peptide, it could not be replaced by the latter one. To induce the assembly, both M-PMV NC(15) and HIV-1 SP1 must be followed by a short peptide that is rich in basic residues. This region either can be specific, i.e., derived from the downstream NC sequence, or can be a nonspecific positively charged peptide. However, it cannot be replaced by heterologous interaction domains either from GCN4 or from CREB. In summary, we report here a novel M-PMV spacer-like domain that is functionally similar to other retroviral spacer peptides and contributes to the assembly of immature-virus-like particles.
- MeSH
- buněčné linie MeSH
- DNA primery genetika MeSH
- DNA virů genetika MeSH
- Escherichia coli genetika ultrastruktura virologie MeSH
- HIV-1 fyziologie genetika MeSH
- lidé MeSH
- Masonův-Pfizerův opičí virus fyziologie genetika ultrastruktura MeSH
- molekulární sekvence - údaje MeSH
- multimerizace proteinu MeSH
- mutageneze MeSH
- nukleokapsida - proteiny fyziologie genetika chemie MeSH
- rekombinantní proteiny genetika chemie metabolismus MeSH
- sekvence aminokyselin MeSH
- sekvence nukleotidů MeSH
- sekvenční homologie aminokyselin MeSH
- sestavení viru fyziologie genetika MeSH
- terciární struktura proteinů MeSH
- transmisní elektronová mikroskopie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
