scholarly journals Knockdown of Dehydrodolichyl Diphosphate Synthase in the Drosophila Retina Leads to a Unique Pattern of Retinal Degeneration

2021 ◽  
Vol 14 ◽  
Author(s):  
Tal Brandwine ◽  
Reut Ifrah ◽  
Tzofia Bialistoky ◽  
Rachel Zaguri ◽  
Elisheva Rhodes-Mordov ◽  
...  
Keyword(s):  
Western Blot ◽  
Retinal Degeneration ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Molecular Mechanisms ◽  
Retinal Disease ◽  
Chain Elongation ◽  
Missense Mutations ◽  
Unique Pattern ◽  
Abnormal Accumulation

Dehydrodolichyl diphosphate synthase (DHDDS) is a ubiquitously expressed enzyme that catalyzes cis-prenyl chain elongation to produce the poly-prenyl backbone of dolichol. It appears in all tissues including the nervous system and it is a highly conserved enzyme that can be found in all animal species. Individuals who have biallelic missense mutations in the DHDDS gene are presented with non-syndromic retinitis pigmentosa with unknown underlying mechanism. We have used the Drosophila model to compromise DHDDS ortholog gene (CG10778) in order to look for cellular and molecular mechanisms that, when defective, might be responsible for this retinal disease. The Gal4/UAS system was used to suppress the expression of CG10778 via RNAi-mediated-knockdown in various tissues. The resulting phenotypes were assessed using q-RT-PCR, transmission-electron-microscopy (TEM), electroretinogram, antibody staining and Western blot analysis. Targeted knockdown of CG10778-mRNA in the early embryo using the actin promoter or in the developing wings using the nub promoter resulted in lethality, or wings loss, respectively. Targeted expression of CG10778-RNAi using the glass multiple reporter (GMR)-Gal4 driver (GMR-DHDDS-RNAi) in the larva eye disc and pupal retina resulted in a complex phenotype: (a) TEM retinal sections revealed a unique pattern of retinal-degeneration, where photoreceptors R2 and R5 exhibited a nearly normal structure of their signaling-compartment (rhabdomere), but only at the region of the nucleus, while all other photoreceptors showed retinal degeneration at all regions. (b) Western blot analysis revealed a drastic reduction in rhodopsin levels in GMR-DHDDS-RNAi-flies and TEM sections showed an abnormal accumulation of endoplasmic reticulum (ER). To conclude, compromising DHDDS in the developing retina, while allowing formation of the retina, resulted in a unique pattern of retinal degeneration, characterized by a dramatic reduction in rhodopsin protein level and an abnormal accumulation of ER membranes in the photoreceptors cells, thus indicating that DHDDS is essential for normal retinal formation.

scholarly journals DIAPH1 Is Upregulated and Inhibits Cell Apoptosis through ATR/p53/Caspase-3 Signaling Pathway in Laryngeal Squamous Cell Carcinoma

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Jiechao Yang ◽  
Liang Zhou ◽  
Yanping Zhang ◽  
Juan Zheng ◽  
Jian Zhou ◽  
...  
Keyword(s):  
Squamous Cell Carcinoma ◽  
Western Blot ◽  
Cell Carcinoma ◽  
Squamous Cell ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Molecular Mechanisms ◽  
Caspase 3 ◽  
Laryngeal Squamous Cell Carcinoma ◽  
Poor Overall Survival

Cancer bioinformatics has been used to screen possible key cancer genes and pathways. Here, through bioinformatics analysis, we found that high expression of diaphanous related formin 1 (DIAPH1) was associated with poor overall survival in head and neck squamous cell carcinoma and laryngeal squamous cell carcinoma (LSCC). The effect of DIAPH1 in LSCC has not been previously investigated. Therefore, we evaluated the expression, function, and molecular mechanisms of DIAPH1 in LSCC. Immunohistochemistry and western blot analysis confirmed the significant upregulation of DIAPH1 in LSCC. We used DIAPH1 RNA interference to construct two DIAPH1-knockdown LSCC cell lines, AMC-HN-8 and FD-LSC-1, and validated the knockdown efficiency. Flow cytometry data showed that DIAPH1 inhibited apoptosis. Further, western blot analysis revealed that DIAPH1 knockdown increased the protein levels of ATR, p-p53, Bax, and cleaved caspase-3, -8, and -9. Thus, DIAPH1 is upregulated in LSCC and may act as an oncogene by inhibiting apoptosis through the ATR/p53/caspase-3 pathway in LSCC cells.

scholarly journals Identification of Tisp40 as an Essential Regulator of Renal Tubulointerstitial Fibrosis via TGF-β/Smads Pathway

2017 ◽  
Vol 42 (2) ◽  
pp. 697-712 ◽  
Author(s):  
Cheng-cheng Xiao ◽  
Jie Zhang ◽  
Peng-cheng Luo ◽  
Cong Qin ◽  
Yang Du ◽  
...  
Keyword(s):  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Renal Fibrosis ◽  
Molecular Mechanisms ◽  
Ischemia Reperfusion ◽  
Critical Role ◽  
Tubulointerstitial Fibrosis ◽  
Mesenchymal Transition ◽  
Renal Tubulointerstitial Fibrosis

Background: Tisp40, a transcription factor of the CREB/CREM family, is involved in cell proliferation, differentiation and other biological functions, but its role in renal tubulointerstitial fibrosis is unknown. Methods: In our study, we investigated the effects of Tisp40 on extracellular matrix (ECM) accumulation, epithelial-mesenchymal transition (EMT) and the underlying molecular mechanisms in transforming growth factor-β (TGF-β)-stimulated TCMK-1 cells by quantitative real-time polymerase chain reaction (qPCR), Western blot analysis and immunofluorescence in vitro, and further explored the role of Tisp40 on renal fibrosis induced by ischemia-reperfusion (I/R) by qPCR, Western blot analysis, hydroxyproline analysis, Masson trichrome staining and immunohistochemistry staining in vivo. Results: The data showed that Tisp40 was upregulated in a model of renal fibrosis induced by I/R injury (IRI). Upon IRI, Tisp40-deficient mice showed attenuated renal fibrosis compared with wild-type mice. Furthermore, the expression of α-smooth muscle actin, E-cadherin, fibronectin, and collagen I was suppressed. Tisp40 overexpression aggravated ECM accumulation and EMT in the TGF-β-stimulated TCMK-1 cell line, whereas the opposite occurred in cells treated with small interfering RNA (siRNA) targeting Tisp40. Importantly, it is changes in the Smad pathway that attenuate renal fibrosis. Conclusion: These findings suggest that Tisp40 plays a critical role in the TGF-β/ Smads pathway involved in this process. Hence, Tisp40 could be a useful therapeutic target in the fight against renal tubulointerstitial fibrosis.

Abstract 65: Desmin Preamyloid Oligomers in Experimental Heart Failure and Cultured Cardiac Myocytes

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Peter Rainer ◽  
Dong I Lee ◽  
Matteo Sorge ◽  
Carlo Guarnieri ◽  
Charles G Glabe ◽  
...  
Keyword(s):  
Heart Failure ◽  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Molecular Mechanisms ◽  
Ventricular Myocytes ◽  
Preliminary Evidence ◽  
Cardiac Cells ◽  
Neonatal Rat ◽  
Genetic Mutations

Background: Heart Failure (HF) is one of the main causes of morbidity and mortality in westernized countries but the molecular mechanisms underlying its development are still unclear. A paradigm-shifting view focuses on the accumulation of preamyloid oligomers (PAOs), similar to those observed in Alzheimer disease, as a potential mechanism of cardiac toxicity. We reported that differential desmin phosphorylation at serines (S) 27 and 31 could drive the formation of PAOs in the heart, in the absence of genetic mutations. We sought to establish the identity of the molecular seed triggering the nucleation of cardiac PAOs in an experimental model of HF and in cultured cardiac cells. Methods: Mice were subjected to transverse aortic constriction (TAC) for 4 weeks (FS% = 29.3±2.6, P=0.0001). Alternatively, neonatal rat ventricular myocytes were transduced with lentiviral vectors carrying alanine (A) or phospho-mimetic aspartate (D) desmin double mutants at S27 and S31, fused with GFP. Protein homogenates were subjected to western blot analysis with fluorescent co-staining using the A11 anti-PAOs and anti-desmin antibodies. Transduced cells were also subjected to live imaging to assess phenotype. Results: Co-western blot analysis of both TAC mice and phospho-mimetic mutant cells revealed the colocalization of PAOs with desmin modified (potentially cleaved) forms. Preamyloid oligomers and a desmin fragment were both increased in TAC mice vs. controls (2.8-fold, P=0.023 and 1.8-fold, P=0.038, respectively). The DD mutant, mimicking the doubly phosphorylated desmin that we hypothesized is the physiological form, showed a healthier phenotype in terms of number of spontaneously contracting cells (P=0.041) and incorporation of GFP-desmin at the Z-discs (P=0.0027), whereas the mono-phosphomimetic mutant (AD) resulted in the increase of desmin positive aggregates (P=0.0014). Conclusions: This preliminary evidence suggests that desmin modified forms represent the seed triggering the formation of cardiac PAOs, in the absence of genetic mutations. The accumulation of desmin PAOs could therefore represent an overarching mechanism underlying the deterioration of cardiac function in HF.

scholarly journals Effects of Betaine on LPS-Stimulated Activation of Microglial M1/M2 Phenotypes by Suppressing TLR4/NF-κB Pathways in N9 Cells

Molecules ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 367 ◽  
Author(s):  
Hui Shi ◽  
Xiao-Long Wang ◽  
Hong-Feng Quan ◽  
Lin Yan ◽  
Xiu-Ying Pei ◽  
...  
Keyword(s):  
Western Blot ◽  
Inflammatory Cytokines ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Molecular Mechanisms ◽  
Morphological Changes ◽  
Arginase 1 ◽  
Iκb Kinase ◽  
Anti Inflammatory

Microglia mediate multiple facets of neuroinflammation. They can be phenotypically divided into a classical phenotype (pro-inflammatory, M1) or an alternative phenotype (anti-inflammatory, M2) with different physiological characteristics and biological functions in the inflammatory process. Betaine has been shown to exert anti-inflammatory effects. In this study, we aimed to verify the anti-inflammatory effects of betaine and elucidate its possible molecular mechanisms of action in vitro. Lipopolysaccharide (LPS)-activated microglial cells were used as an inflammatory model to study the anti-inflammatory efficacy of betaine and explore its mechanism of regulating microglial polarisation by investigating the morphological changes and associated inflammatory changes. Cytokine and inflammatory mediator expression was also measured by ELISA, flow cytometry, immunofluorescence, and western blot analysis. Toll-like receptor (TLR)-myeloid differentiation factor 88 (Myd88)-nuclear factor-kappa B (NF-κB) p65, p-NF-κB p65, IκB, p-IκB, IκB kinase (IKK), and p-IKK expression was determined by western blot analysis. Betaine significantly mitigated the production of pro-inflammatory cytokines and increased the release of anti-inflammatory cytokines. It promoted the conversion of the microglia from M1 to M2 phenotype by decreasing the expression of inducible nitric oxide synthase and CD16/32 and by increasing that of CD206 and arginase-1. Betaine treatment inhibited the TLR4/NF-κB pathways by attenuating the expression of TLR4-Myd88 and blocking the phosphorylation of IκB and IKK. In conclusion, betaine could significantly alleviate LPS-induced inflammation by regulating the polarisation of microglial phenotype; thus, it might be an effective therapeutic agent for neurological disorders.

scholarly journals Tissue-specific Tropomyosin Isoform Composition

2005 ◽  
Vol 53 (5) ◽  
pp. 557-570 ◽  
Author(s):  
Galina Schevzov ◽  
Bernadette Vrhovski ◽  
Nicole S. Bryce ◽  
Sarah Elmir ◽  
Min Ru Qiu ◽  
...  
Keyword(s):  
Alternative Splicing ◽  
Western Blot ◽  
Blot Analysis ◽  
Actin Filaments ◽  
Western Blot Analysis ◽  
Molecular Mechanisms ◽  
Experimental Systems ◽  
Mouse Tissues ◽  
Intracellular Compartments ◽  
Microfilament System

Four distinct genes encode tropomyosin (Tm) proteins, integral components of the actin microfilament system. In non-muscle cells, over 40 Tm isoforms are derived using alternative splicing. Distinct populations of actin filaments characterized by the composition of these Tm isoforms are found differentially sorted within cells ( Gunning et al. 1998b ). We hypothesized that these distinct intracellular compartments defined by the association of Tm isoforms may allow for independent regulation of microfilament function. Consequently, to understand the molecular mechanisms that give rise to these different microfilaments and their regulation, a cohort of fully characterized isoform-specific Tm antibodies was required. The characterization protocol initially involved testing the specificity of the antibodies on bacterially produced Tm proteins. We then confirmed that these Tm antibodies can be used to probe the expression and subcellular localization of different Tm isoforms by Western blot analysis, immunofluorescence staining of cells in culture, and immunohistochemistry of paraffin wax-embedded mouse tissues. These Tm antibodies, therefore, have the capacity to monitor specific actin filament populations in a range of experimental systems.

scholarly journals Identification of potential key genes associated with termination phase of rat liver regeneration through microarray analysis

2021 ◽  
Keyword(s):  
Western Blot ◽  
Liver Regeneration ◽  
Microarray Analysis ◽  
Rat Liver ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Molecular Mechanisms ◽  
Enrichment Analysis ◽  
Hub Genes ◽  
Termination Phase

Background and objective: Liver regeneration (LR) is a complex process influenced by various genes and pathways, the majority of the of research on LR focus on the initiation and proliferation phase while studies on termination phase is lacking. We aimed to identify potential genes and reveal the underlying the molecular mechanisms involved in the precise regulation of liver size during the termination phase of LR. Materials and methods: We obtained the rat liver tissue gene datasets (GSE63742) collected following partial hepatectomy (PH) from the Gene Expression Omnibus (GEO) of the National Center for Biotechnology Information (NCBI), from which, this study screened the late stage LR samples (7 days post-PH) using the R/Bioconductor packages for the identification of differentially expressed genes (DEGs). Afterwards, we performed enrichment analysis using the database for annotation visualization and integrated discovery (DAVID) online tool. Moreover, the Search Tool for the Retrieval of Interacting proteins (STRING) database was employed to construct protein-protein interaction (PPI) networks based on those identified DEGs; the PPI network was then used by Cytoscape software to predict hub genes and nodes. Animal experimentation (Rat PH model) was performed to acquire liver tissues which were then used for western blot analysis to verify our results. Results: The present study identified together 74 significant DEGs, among which, 51 showed up-regulation while 23 presented as down-regulated. As revealed by KEGG pathway enrichment analysis, DEGs were mostly related to pathways such as retinol metabolism, steroid hormone synthesis, transforming growth factor-β (TGF-β) and mitogen-activated protein kinase (MAPK) signaling. In addition, as suggested by GO enrichment analysis, DEGs were mostly related to the cyclooxygenase P450 pathway, negative regulation of Notch signaling pathway, aromatase activity, steroid hydroxylase activity, exosomes, and extracellular domain. Analyses based on STRING database and Cytoscape software identified genes like Ste2 and Btg2 as the hub genes in the termination stage LR. The obtained results were confirmed by Western blot analysis. Conclusions: Taken together, the microarray analysis in this study suggests that DEGs such as Ste2 and Btg2 are the hub genes, which are associated with the regulation of termination stage LR, while the molecular mechanisms are possibly related to the MAPK and TGF-β signal transduction pathways.

scholarly journals IFN-CSP Inhibiting Hepatitis B Virus in HepG2.2.15 Cells Involves JAK-STAT Signal Pathway

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xuemei Lu ◽  
Jie Wang ◽  
Xiaobao Jin ◽  
Yanting Huang ◽  
Wenting Zeng ◽  
...  
Keyword(s):  
Hepatitis B ◽  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Molecular Mechanisms ◽  
Core Protein ◽  
Hbv Dna ◽  
Enzyme Linked Immunosorbent Assay ◽  
High Dose ◽  
Oligoadenylate Synthetase

Frequent and high-dose administration of interferon to patients with viral hepatitis results in various side effects. In our previous study, a novel liver-targeting interferon (IFN-CSP) combiningPlasmodiumregion I peptide with IFNα2b was successfully designed and expressed in theEscherichia coliexpression systems. This targeting would target the IFNα2b specifically to the liver, thus reducing the adverse events. In the present study, we further investigated the anti-HBV effects and molecular mechanisms of recombinant IFN-CSP in HepG2.2.15 cell line. Hepatitis B surface antigen (HBsAg) and HBe antigen (HBeAg) in the culture supernatants were analyzed by enzyme-linked immunosorbent assay (ELISA). HBV-DNA was measured by real-time quantitative PCR. HBV core protein was assayed by immunofluorescent and western blot analysis. The expressions of signal transducers and transactivator 1 (STAT1), STAT2, IFN regulatory factor 9 (IRF-9), and 2′-5′-oligoadenylate synthetase 1 (OAS1) were investigated by the reverse transcription PCR and western blot analysis. Results indicate IFN-CSP efficiently inhibited HBsAg and HBeAg secretion, HBV-DNA replication, and HBV core protein expression in HepG2.2.15 cells. The anti-HBV mechanisms involve activation of JAK-STAT signaling and increase of the anti-HBV protein OAS expression. IFN-CSP could be a good substitute for IFNα2b for anti-HBV treatment.

Radiosensitivity of glioma to Gamma Knife treatment enhanced in vitro and in vivo by RNA interfering Ku70 that is mediated by a recombinant adenovirus

2010 ◽  
Vol 113 (Special_Supplement) ◽  
pp. 228-235 ◽  
Author(s):  
Qiang Jia ◽  
Yanhe Li ◽  
Desheng Xu ◽  
Zhenjiang Li ◽  
Zhiyuan Zhang ◽  
...  
Keyword(s):  
Western Blot ◽  
Gamma Knife ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Glioma Cells ◽  
C6 Glioma ◽  
C6 Glioma Cells ◽  
C6 Cells

Object The authors sought to evaluate modification of the radiation response of C6 glioma cells in vitro and in vivo by inhibiting the expression of Ku70. To do so they investigated the effect of gene transfer involving a recombinant replication-defective adenovirus containing Ku70 short hairpin RNA (Ad-Ku70shRNA) combined with Gamma Knife treatment (GKT). Methods First, Ad-Ku70shRNA was transfected into C6 glioma cells and the expression of Ku70 was measured using Western blot analysis. In vitro, phenotypical changes in C6 cells, including proliferation, cell cycle modification, invasion ability, and apoptosis were evaluated using the MTT (3′(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide) assay, Western blot analysis, and cell flow cytometry. In vivo, parental C6 cells transfected with Ad-Ku70shRNA were implanted stereotactically into the right caudate nucleus in Sprague-Dawley rats. After GKS, apoptosis was analyzed using the TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling) method. The inhibitory effects on growth and invasion that were induced by expression of proliferating cell nuclear antigen and matrix metalloproteinase–9 were determined using immunohistochemical analyses. Results The expression of Ku70 was clearly inhibited in C6 cells after transfection with Ad-Ku70shRNA. In vitro following transfection, the C6 cells showed improved responses to GKT, including suppression of proliferation and invasion as well as an increased apoptosis index. In vivo following transfection of Ad-Ku70shRNA, the therapeutic efficacy of GKT in rats with C6 gliomas was greatly enhanced and survival times in these animals were prolonged. Conclusions Our data support the potential for downregulation of Ku70 expression in enhancing the radiosensitivity of gliomas. The findings of our study indicate that targeted gene therapy–mediated inactivation of Ku70 may represent a promising strategy in improving the radioresponsiveness of gliomas to GKT.

Synthesis and Characterization of Quinoline-3-Carboxamide Derivatives as Inhibitors of the ATM Kinase

2020 ◽  
Vol 20 (23) ◽  
pp. 2070-2079
Author(s):  
Srimadhavi Ravi ◽  
Sugata Barui ◽  
Sivapriya Kirubakaran ◽  
Parul Duhan ◽  
Kaushik Bhowmik
Keyword(s):  
Western Blot ◽  
Cancer Cells ◽  
Cell Line ◽  
Cell Lines ◽  
Cancer Cell ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Cancer Cell Lines ◽  
Atm Kinase ◽  
Cytotoxicity Studies

Background: The importance of inhibiting the kinases of the DDR pathway for radiosensitizing cancer cells is well established. Cancer cells exploit these kinases for their survival, which leads to the development of resistance towards DNA damaging therapeutics. Objective: In this article, the focus is on targeting the key mediator of the DDR pathway, the ATM kinase. A new set of quinoline-3-carboxamides, as potential inhibitors of ATM, is reported. Methods: Quinoline-3-carboxamide derivatives were synthesized and cytotoxicity assay was performed to analyze the effect of molecules on different cancer cell lines like HCT116, MDA-MB-468, and MDA-MB-231. Results: Three of the synthesized compounds showed promising cytotoxicity towards a selected set of cancer cell lines. Western Blot analysis was also performed by pre-treating the cells with quercetin, a known ATM upregulator, by causing DNA double-strand breaks. SAR studies suggested the importance of the electron-donating nature of the R group for the molecule to be toxic. Finally, Western-Blot analysis confirmed the down-regulation of ATM in the cells. Additionally, the PTEN negative cell line, MDA-MB-468, was more sensitive towards the compounds in comparison with the PTEN positive cell line, MDA-MB-231. Cytotoxicity studies against 293T cells showed that the compounds were at least three times less toxic when compared with HCT116. Conclusion: In conclusion, these experiments will lay the groundwork for the evolution of potent and selective ATM inhibitors for the radio- and chemo-sensitization of cancer cells.

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