Induction of Cytoplasmic Rods and Rings Structures by Inhibition of the CTP and GTP Synthetic Pathway in Mammalian Cells

Background: Cytoplasmic filamentous rods and rings (RR) structures were identified using human autoantibodies as probes. In the present study, the formation of these conserved structures in mammalian cells and functions linked to these structures were examined. Methodology/Principal Findings: Distinct cytoplasmic rods (,3–10 mm in length) and rings (,2–5 mm in diameter) in HEp-2 cells were initially observed in immunofluorescence using human autoantibodies. Co-localization studies revealed that, although RR had filament-like features, they were not enriched in actin, tubulin, or vimentin, and not associated with centrosomes or other known cytoplasmic structures. Further independent studies revealed that two key enzymes in the nucleotide synthetic pathway cytidine triphosphate synthase 1 (CTPS1) and inosine monophosphate dehydrogenase 2 (IMPDH2) were highly enriched in RR. CTPS1 enzyme inhibitors 6-diazo-5-oxo-L-norleucine and Acivicin as well as the IMPDH2 inhibitor Ribavirin exhibited dose-dependent induction of RR in.95 % of cells in all cancer cell lines tested as well as mouse primary cells. RR formation by lower concentration of Ribavirin was enhanced in IMPDH2-knockdown HeLa cells whereas it was inhibited in GFP-IMPDH2 overexpressed HeLa cells. Interestingly, RR were detected readily in untreated mouse embryonic stem cells (.95%); upon retinoic acid differentiation, RR disassembled in these cells but reformed when treated with Acivicin

Large area PECVD process using dual rotatable magnetrons

Magnetron PECVD is an emerging technology targeting the possibility to perform a chemical vapor deposition process at fairly high rates over large areas. The paper presents a new setup based on rotatable magnetrons. The precursor hexamethydisiloxane was used to deposit SiOxCy layers on polymer substrates. It could be shown that the formation of redeposition zones on the target can be avoided completely. The discharge voltage drift as it is typical for planar configuration is damped. These advantages could be optained on expense of deposition rate. The maximum achieved value was 180 nm*m/min which is higher than sputtering but lower compared to planar magnetron based PECVD. It could be demonstrated that the technology is stable over several hours deposition time. The optical properties of the layers are well suited for the usage as low refractive index materials in optical layer stacks. All experiments have been carried out on a pilot coater of 600 mm deposition width. Scale-up experiments to 2100 mm targets in a production coater have been done