ABSTRACT
Histone deacetylases (HDACs) are enzymes that remove acetyl groups from É-amino of histone, and their involvement in the development and progression of cancer disorders makes them an interesting therapeutic target. This study seeks to discover new inhibitors that selectively inhibit HDAC enzymes which are linked to deadly disorders like T-cell lymphoma, childhood neuroblastoma, and colon cancer. MOE was used to dock libraries of ZINC database molecules within the catalytic active pocket of target HDACs. The top three hits were submitted to MD simulations ranked on binding affinities and well-occupied interaction mechanisms determined from molecular docking studies. Inside the catalytic active site of HDACs, the two stable inhibitors LIG1 and LIG2 affect the protein flexibility, as evidenced by RMSD, RMSF, Rg, and PCA. MD simulations of HDACs complexes revealed an alteration from extended to bent motional changes within loop regions. The structural deviation following superimposition shows flexibility via a visual inspection of movable loops at different timeframes. According to PCA, the activity of HDACs inhibitors induces structural dynamics that might potentially be utilized to define the nature of protein inhibition. The findings suggest that this study offers solid proof to investigate LIG1 and LIG2 as potential HDAC inhibitors.
ABSTRACT
Background: Focal adhesions (FAs) are highly dynamic complex structures that assembled and disassembled on an ongoing basis. The balance between the two processes mediates various aspects of cell behavior, ranging from cell adhesion to cell migration. Assembly and disassembly processes of FAs are regulated by a variety of cellular signaling proteins and adaptors. We previously demonstrated that local levels of Phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) in MDA-MB-231 cells increases during FA assembly and declines during disassembly. In this study we aimed to investigate whether PtdIns(4,5)P2 regulates FA turnover. Methods: MDA-MB-231 cells were co-transfected with a labeling vinculin (or zyxin) and the PLCð 1-PH biosensor to visualize FA localization and PtdIns(4,5)P2 in the cell membrane. We also used pharmacological inhibitors to determine the mechanism underlying the changes of PtdIns(4,5)P2 level during FA turnover and cell migration. Immunostaining, immunoprecipitation, and Western blotting were used to examine the localization and interaction between phospholipase C (PLC)/phosphatidylinositol 3-kinase (PI3K) FA proteins. Results: We showed that inhibition of PLC, PI3K significantly reduced the decline of PtdIns(4,5)P2 levels within FA disassembly and the slowdown rate of FA turnover and cell migration. We also showed that the inhibition of enzymes implicated in the downstream pathway of PtdIns(4,5)P2, such as diacylglycerol kinase (DAGK) and protein kinase C (PKC) significantly reduced FA turnover time and the speed of cell migration. Additionally, we demonstrated that PLC but not PI3K interact with FAs. In conclusion. Discussion: This study suggests that dynamical changes of PtdIns(4,5)P2 might regulate FA turnover and facilitate cell migration.
ABSTRACT
Background: The assembly and disassembly of the focal adhesions (FA) components occurs throughout life cycle of adhesion, with conservation of balance between removal and recruitment rate during temporal stages. Previous studies have demonstrated that phosphotidyilinositols play a role in regulating FA turnover. However, a little attention has been given to quantify the dynamics changes of Phosphatidylinositol 3,4,5-trisphosphate (PtdIns (3,4,5) P3) within and during fast and slow turnover rates of FA. Methods: In this study, we developed a protein purification MDA-MB-231 breast cancer cell line was used as a model in this study due to high metastatic and motile. These cells were co-transfected with GFP- paxillin/vinculin, as FA marker, and the GFP/mCherry-Btk-PH, as a biosensor to visualize PtdIns (3,4,5) P3. Confocal time-lapse images were used to monitor changes or differences in the local generation of PtdIns (3,4,5) P3 within and during assembly and disassembly of FA. Following transfection, immunostaining was used to examine the spatial co-localization between FA and PtdIns (3,4,5) P3. Results: Our data demonstrated that PtdIns (3,4,5) P3 co-localized with FAs and increase during assembly and decline during disassembly of FA which exhibits slow turnover rates and was in a constant level during assembly and disassembly of FA that displays fast turnover rates. Discussion: Our result suggested that the dynamic changes of PtdIns (3,4,5) P3, it may depend on components undergo turnover, such that early, nascent FA displays fast turnover rates and mature FA exhibits slow turnover rates. Thus, the local enrichment of PtdIns (3,4,5) P3 enhances FA assembly and disassembly activation.
ABSTRACT
BACKGROUND: Parvovirus B19 (B19) infection is linked with various diseases. Cytokines play critical roles in cellular response to viral infection. It has also been reported that's susceptibility of the ABO blood type people to several viral infection. In this study, we evaluated interleukin 6 (IL-6), interleukin 8(IL-8), and interferon gamma (IFN-γ) levels in aborted women infected with parvovirus B19 (B19+/Abr+) and uninfected with B19(B19-/Abr+) in comparison with healthy women (B12-/Abr-) and susceptibility of their RhD blood type to contract B19. METHODS: B19+/Abr+ were diagnosed using IgM and IgG antibodies against B19, and the concentrations of IL-6, IL-8, and IFN-γ were determined using enzyme-linked immunosorbent assay (ELISA) test in both B19+/Abr+, B19-/Abr+, and B19-/Abr-. Here, we also collected blood groups, number of abortion, and gestational ages from 200 B19+/Abr+ along with the same number ofB19-/Abr+ and B19-/Abr-. RESULTS: The levels of IFN-γ were higher in serum of B19-/Abr+andB19+/Abr+ group in comparison to B19-/Abr-, while the serum levels of IL-6, IL-8were increased in B19+/Abr+ group in comparisontoB19-/Abr+ and B19-/Abr-. Our analyzed data also showed that aborted women with RhD+ are more susceptible to contract s B19 than people with RhD- blood type. CONCLUSION: B19 infection may differently modulate the amount of cytokines in the plasma of aborted women. So, it can be suggested that IL-6, IL-8, and IFN-γ potentially useful as markers for inflammation intrauterine. The susceptibility/protection of aborted women against B19 might be determined based on RhD blood type.
