Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.48 (transcriptase)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study, Dicentrarchus labrax encephalitis virus (DlEV), which causes sea bass encephalitis, was propagated in cell culture, thus allowing study of its lytic cycle. DlEV infection of mammalian and fish cells induced different patterns of expression of capsid proteins, which were assembled as virus-like particles, accumulating in the cytoplasm either as diffuse masses or in vesicles, as shown by electron microscopy. These particles correspond to virions, as shown by their ability to induce secondary infection. Fish cells proved to be more permissive for DlEV than mammalian cells, although virus yield remained low. RNA analysis of infected sea bass cells revealed DlEV RNA3, in addition to genomic RNA1 and RNA2, and the presence of the RNA2 minus strand, thus demonstrating the replication of the DlEV genome. In addition, DlEV RNA-dependent RNA polymerase was associated with mature virions even after purification by a CsCl gradient, but it was dissociated when capsids were destabilized. In addition to providing more information about the relatedness of DlEV to the members of the family Nodaviridae, this study shows that fish nodaviruses may not be able to infect as wide a variety of cells as insect nodaviruses can.
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PMID:Fish nodavirus lytic cycle and semipermissive expression in mammalian and fish cell cultures. 918 47

Grafting experiments have revealed that transgenic plants that undergo co-suppression of homologous transgenes and endogenous genes or PTGS of exogenous transgenes produce a sequence-specific systemic silencing signal that is able to propagate from cell to cell and at long distance. Similarly, infection of transgenic plants by viruses that carry (part of) a transgene sequence results in global silencing (VIGS) of the integrated transgenes although viral infection is localized. Systemic PTGS and VIGS strongly resemble recovery from virus infection in non-transgenic plants, leading to protection against secondary infection in newly emerging leaves and PTGS of transiently expressed homologous transgenes. The sequence-specific PTGS signal is probably a transgene product (for example, aberrant RNA) or a secondary product (for example, RNA molecules produced by an RNA-dependent RNA polymerase with transgene RNA as a matrix) that mimics the type of viral RNA that is targeted for degradation by cellular defence. Whether some particular cases of transgene TGS could also rely on the production of such a mobile molecule is discussed.
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PMID:Systemic silencing signal(s). 1099 11