To analyse the role of PKC-dependent phosphorylation in the C-terminus of rCx46 in regulation of rCx46 connexons, truncated mutants rCx46(45.3) and rCx46(44.2) which end before and after PKC-dependent phosphorylation sites respectively were generated.
View Article and Find Full Text PDFThis report shows that temperature is a latent regulator of the voltage-dependent conductance of hemichannels composed of hCx26. The latter were expressed in Xenopus oocytes by injection of a mixture of hCx26 cRNA and antisense of endogenous Cx38 (anti-Cx38). At 24-25 degrees C, voltage clamp of oocytes at potentials above -40 mV evoked outward currents which were not observed in control oocytes.
View Article and Find Full Text PDFTwo-photon polymerization technique was applied to generate three-dimensional (3D) scaffold-like structures using the photosensitive organic-inorganic hybrid polymer ORMOCER. The structures were studied with respect to potential applications as scaffold for tissue engineering. Cell counting and comet assay, respectively, demonstrated that doubling time and DNA strand breaks of CHO cells, GFSHR-17 granulosa cells, GM-7373 endothelial cells, and SH-SY5Y neuroblastoma cells were not affected by ORMOCER.
View Article and Find Full Text PDFNanostructures of lysozyme molecules adsorbed to mica were generated by the tip of an atomic force microscope in contact, tapping, and force-distance mode in aqueous solution. In contact mode at high ionic strength and adjusted lysozyme concentration a monolayer of defined pattern and orientation could be formed by the scan process of the tip. A lysozyme monolayer with minimal pattern size of about 60 nm was achieved by line scan.
View Article and Find Full Text PDFBiochim Biophys Acta
December 2005
Wild type connexin 46 of rat (wtrCx46), and human connexin 26 (wthCx26) and derivates from rCx46 elongated at the C-terminus by 25 amino acids (rCx46Ct) as well as C-terminal truncated constructs (rCx28.1, rCx45.3) were expressed in frog oocytes of Xenopus laevis.
View Article and Find Full Text PDFIn the present study we examined the trafficking pathways of connexin49 (Cx49) fused to green fluorescent protein (GFP) in polar and non-polar cell lines. The Cx49 gene was isolated from ovine lens by RT-PCR. Cx49 cDNA was fused to GFP and the hybrid cDNA was transfected into several cell lines.
View Article and Find Full Text PDFThe recently described increase in DNA strand breaks of cultured human diploid fibroblasts after intermittent exposure to extremely-low-frequency electromagnetic fields (ELF-EMF) of more than about 70 microT ELF-EMF is difficult to explain by a direct induction of covalent bond disruption. Therefore the hypothesis has been tested that ELF-EMF-induced DNA strand breaks might be mediated by cellular processes that cause alteration of the intracellular concentration of free calcium ([Ca2+]i) and/or the membrane potential (DeltaPsi(m)). [Ca2+]i was determined by the ratiometric fura-2 technique.
View Article and Find Full Text PDFThe effect of calmodulin (CaM) antagonists W7, trifluoperazine (TFP) and a calmodulin inhibitory peptide on gap junction coupling in isolated Hensen cells of the organ of Corti was analysed by the double whole-cell patch-clamp technique. Addition of the conventional antagonists W7 and TFP in the micromolar range caused a rapid decrease of gap junction conductance after a delay of a few minutes in a dose-dependent manner. Fluorescence spectroscopy of cytoplasmic free calcium concentration ([Ca(2+)](i)) by Fura-2 showed no significant change of [Ca(2+)](i) by W7.
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