Search results for "Reporter"
showing 10 items of 166 documents
Relative contribution of different l-arginine sources to the substrate supply of endothelial nitric oxide synthase
2011
In certain cases of endothelial dysfunction l-arginine becomes rate-limiting for NO synthesis in spite of sufficiently high plasma concentrations of the amino acid. To better understand this phenomenon, we investigated routes of substrate supply to endothelial nitric oxide synthase (eNOS). Our previous data with human umbilical vein (HUVEC) and EA.hy.926 endothelial cells demonstrated that eNOS can obtain its substrate from the conversion of l-citrulline to l-arginine and from protein breakdown. In the present study, we determined the quantitative contribution of proteasomal and lysosomal protein degradation and investigated to what extent extracellular peptides and l-citrulline can provide…
Studies of the physicochemical and structural properties of self-assembling cationic pyridine derivatives as gene delivery agents.
2015
New amphiphilic pyridine derivatives containing dodecyloxycarbonyl substituents at positions 3 and 5 and cationic moieties at positions 2 and 6 have been designed and synthesised. Compounds of this type can be considered as synthetic lipids. The corresponding 1,4-dihydropyridine (1,4-DHP) derivatives have earlier been proposed as a promising tool for plasmid DNA (pDNA) delivery in vitro. In this work studies of the self-assembling properties of amphiphilic pyridine derivatives leading to the formation of liposomes, determination of particle size, zeta-potential and critical micelle concentration (CMC) with dynamic light scattering (DLS) measurements are described. Furthermore, thermal analy…
Pulsed Electric Fields Alter Expression of NF-κB Promoter-Controlled Gene
2021
The possibility to artificially adjust and fine‐tune gene expression is one of the key mile-stones in bioengineering, synthetic biology, and advanced medicine. Since the effects of proteins or other transgene products depend on the dosage, controlled gene expression is required for any ap-plications, where even slight fluctuations of the transgene product impact its function or other critical cell parameters. In this context, physical techniques demonstrate optimistic perspectives, and pulsed electric field technology is a potential candidate for a noninvasive, biophysical gene regulator, exploiting an easily adjustable pulse generating device. We exposed mammalian cells, transfected with a…
Alkoxy-styryl DCDHF fluorophores
2010
A photostable dicyanomethylenedihydrofuran fluorophore which contains electron-donating alkoxy groups is described. This chromophore is highly environmentally-sensitive, which is a remarkable property for a fluorescent reporter. Its light excitation also enables, in low viscous solvents, the formation of dark states whose radical or triplet nature is ruled out.
Phosphorothioate cap analogs increase stability and translational efficiency of RNA vaccines in immature dendritic cells and induce superior immune r…
2010
Vaccination with in vitro transcribed RNA coding for tumor antigens is considered a promising approach for cancer immunotherapy and has already entered human clinical testing. One of the basic objectives for development of RNA as a drug is the optimization of immunobioavailability of the encoded antigen in vivo. By analyzing the effect of different synthetic 5' mRNA cap analogs on the kinetics of the encoded protein, we found that m(2)(7,2'-O)Gpp(S)pG (beta-S-ARCA) phosphorothioate caps, in particular the D1 diastereoisomer, profoundly enhance RNA stability and translational efficiency in immature but not mature dendritic cells. Moreover, in vivo delivery of the antigen as beta-S-ARCA(D1)-c…
Requirement of Retinoic Acid Receptor Isotypes α, β, and γ during the Initial Steps of Neural Differentiation of PCC7 Cells
2005
Retinoic acid (RA) is indispensable for morphogenesis and differentiation of several tissues, including the nervous system. The requirement of the RA receptor (RAR) isotypes alpha, beta, and gamma and the putative role of retinoid X receptor-(RXR) signaling in RA-induced neural differentiation, was analyzed. For this compound-selective retinoids and the murine embryonal carcinoma cell line PCC7, a model system for RA-dependent neural differentiation was used. The present paper shows that proliferating PCC7 cells primarily express RXRalpha and RARalpha, lower levels of RXRbeta, and barely detectable amounts of RARbeta, RARgamma, and RXRgamma. At receptor-selective concentrations, only a RARa…
The induction of cytochrome P450 3A5 (CYP3A5) in the human liver and intestine is mediated by the xenobiotic sensors pregnane X receptor (PXR) and co…
2004
Induction of cytochrome P450 3A (CYP3A) by xenobiotics may lead to clinically relevant drug interactions. In contrast with other CYP3A family members, studies on the inducibility of CYP3A5 indicate conflicting results. We report the induction of CYP3A5 mRNA in 13 of 16 hepatocyte preparations exposed to rifampin. Furthermore, induction of CYP3A5 mRNA was observed in intestinal biopsies in three of eight probands following exposure to the antibiotic. The highest absolute levels of CYP3A5 transcripts were found following rifampin treatment in hepatocytes and intestines from carriers of CYP3A5*1 alleles. Elucidation of the mechanism involved in CYP3A5 induction revealed that constitutively act…
Specific Binding of Baculoviruses Displaying gp64 Fusion Proteins to Mammalian Cells
2001
Viral vectors displaying specific ligand binding moieties have raised an increasing interest in the area of targeted gene therapy. In this report, we describe baculovirus vectors displaying either a functional single chain antibody fragment (scFv) specific for the carcinoembryonic antigen (CEA) or the synthetic IgG binding domains (ZZ) derived from protein A of Staphylococcus aureus. In addition, the vectors were engineered to incorporate a reporter gene encoding the enhanced green fluorescent protein (EGFP) under the transcriptional regulation of the cytomegalovirus (CMV) IE promoter. Display of the targeting moieties on the viral surface was achieved through fusion to the N-terminus of gp…
The Tobacco mosaic virus movement protein associates with but does not integrate into biological membranes
2014
Plant positive-strand RNA viruses require association with plant cell endomembranes for viral translation and replication, as well as for intra- and intercellular movement of the viral progeny. The membrane association and RNA binding of the Tobacco mosaic virus (TMV) movement protein (MP) are vital for orchestrating the macromolecular network required for virus movement. A previously proposed topological model suggests that TMV MP is an integral membrane protein with two putative -helical transmembrane (TM) segments. Here we tested this model using an experimental system that measured the efficiency with which natural polypeptide segments were inserted into the ER membrane under conditions…
Nitrate/oxygen co-sensing by an NreA/NreB sensor complex ofStaphylococcus carnosus
2013
In Staphylococci maximal induction of nitrate reductase (narGHJI genes) requires anaerobic conditions, the presence of nitrate, and the NreABC regulatory system. Aerobic regulation is effected by the NreB/NreC two-component system. The role of the nitrate receptor NreA in nitrate induction and its relation to aerobic regulation was analysed in Staphylococcus carnosus. Nitrate induction of a narG-lip reporter gene required presence of NreB/NreC. When nreA was deleted, nitrate was no longer required for maximal induction, suggesting that NreA is a nitrate regulated inhibitor of NreB/NreC. In vitro, NreA and mutant NreA(Y95A) decreased NreB phosphorylation in part or completely, which was due …