Two inhibitors of glycosylation, glucosamine and tunicamycin, were utilized to examine the effect of glycosylation inhibition in mouse neuroblastoma N18 cells on the degradation of membrane glycoproteins synthesized before addition of the inhibitor. Treatment with 10 mM-glucosamine resulted in inhibition of glycosylation after 2h, as measured by [3H]fucose incorporation into acid-insoluble macr...

Tetanus toxin is known to bind neuronal tissue selectively. To study the interactions of this potent neurotoxin in an intact cell system, the binding of 125I-tetanus toxin was characterized in a neuroblastoma retina hybrid cell line, N18-RE-105. The binding of 125I-tetanus toxin to membranes prepared from N18-RE-105 cells showed many similarities to the interactions of 125I-toxin with rat synap...

Deoxyribonuclease I (DNase I) is known to be a glycoprotein, and two potential N-linked glycosylation sites (N18 and N106) are known for mammalian enzymes. In the present study, N18 and N106 were mutated in order to investigate the biological role of N-linked glycosylation in three mammalian (human, bovine, and equine) DNases I. The enzyme activities of N18Q and N106Q were lower than that of th...

The microstructure and fatigue performance of three sub-solvus heat treated nickel based disc superalloys for turbine disc applications are reported. The alloy variants studied are RR1000, N18 and Udimet 720 Low Interstitial (U720Li), with the latter tested both in a standard and large grain variant (LG). Their microstructures are examined in terms of grain and gamma prime size (γ'). Fatigue cr...

Sindbis virus (SV) is an alphavirus that causes encephalitis in mice and results in age-dependent mortality. The outcome is dependent on the virus strain. Residues at 55 and 172 in the E2 glycoprotein determine the neurovirulence for mice of different ages and the efficiency of replication in the nervous system and neuronal cells. To determine the effects of these two residues on the initial st...

At the initial phase of cell differentiation in mouse neuroblastoma (N18) induced by dibutyrylcyclic AMP (dbcAMP), an additional site of histone H1 was extensively phosphorylated. Forskolin and various phosphodiesterase inhibitors also induced both cell differentiation and H1 phosphorylation at the identical site. The phosphorylation preferentially occurred in a single H1 subtype (H1c) among th...

Japanese encephalitis virus (JEV), a mosquito-borne flavivirus, replicates primarily at the endoplasmic reticulum and thereby triggers apoptosis of infected cells. This study investigated the hierarchical activation of the caspase network induced by JEV infection. It was found that JEV activated the initiators caspase-8 and -9, as well as effector caspase-3, in infected baby hamster kidney and ...

Aspartylglucosaminuria (AGU) is a neurodegenerative lysosomal storage disease that is caused by mutations in the gene encoding for a soluble hydrolase, aspartylglucosaminidase (AGA). In this study, we have used our recently developed mouse model for AGU and analyzed processing, intracellular localization, and endocytosis of recombinant AGA in telencephalic AGU mouse neurons in vitro. The proces...

Clonal cells (N18) of the mouse neuroblastoma C-1300 can be induced to undergo a morphological differentiation characterized by the outgrowth of very long neurites (> 150 microns) that contain many microtubules. Because the marked increase in the number and length of microtubules is apparently not due to an increase in the concentration of tubulin subunits, the possible role of additional macro...

Oxidative stress has been proposed as a common mediator of apoptotic death. To investigate further the role of oxidants in this process we have studied the effects of antioxidants on Sindbis virus (SV)-induced apoptosis in two cell lines, AT-3 (a prostate carcinoma line) and N18 (a neuroblastoma line). The thiol antioxidant, N-acetylcysteine (NAC), at concentrations above 30 mM, completely abro...