Search results for "Complex protein"
showing 7 items of 57 documents
A Trans-amplifying RNA Vaccine Strategy for Induction of Potent Protective Immunity
2019
Here, we present a potent RNA vaccine approach based on a novel bipartite vector system using trans-amplifying RNA (taRNA). The vector cassette encoding the vaccine antigen originates from an alphaviral self-amplifying RNA (saRNA), from which the replicase was deleted to form a transreplicon. Replicase activity is provided in trans by a second molecule, either by a standard saRNA or an optimized non-replicating mRNA (nrRNA). The latter delivered 10- to 100-fold higher transreplicon expression than the former. Moreover, expression driven by the nrRNA-encoded replicase in the taRNA system was as efficient as in a conventional monopartite saRNA system. We show that the superiority of nrRNA- ov…
dsRNA induces apoptosis through an atypical death complex associating TLR3 to caspase-8
2012
Toll-like receptor 3 (TLR3) is a pattern-recognition receptor known to initiate an innate immune response when stimulated by double-stranded RNA (dsRNA). Components of TLR3 signaling, including TIR domain-containing adapter inducing IFN-α (TRIF), have been demonstrated to contribute to dsRNA-induced cell death through caspase-8 and receptor interacting protein (RIP)1 in various human cancer cells. We provide here a detailed analysis of the caspase-8 activating machinery triggered in response to Poly(I:C) dsRNA. Engagement of TLR3 by dsRNA in both type I and type II lung cancer cells induces the formation of an atypical caspase-8-containing complex that is devoid of classical death receptors…
Casein kinase 2 inhibits HomolD-directed transcription by Rrn7 in Schizosaccharomyces pombe.
2014
In Schizosaccharomyces pombe, ribosomal protein gene (RPG) promoters contain a TATA analogue element called the HomolD box. The HomolD-binding protein Rrn7 forms a complex with the RNA polymerase II machinery. Despite the importance of ribosome biogenesis to cell survival, the mechanisms involved in the regulation of transcription of eukaryotic RPGs are unknown. In this study, we identified Rrn7 as a new substrate of the pleiotropic casein kinase 2 (CK2), which is a regulator of basal transcription. Recombinant Rrn7 from S. pombe, which is often used as a model organism for studying eukaryotic transcription, interacted with CK2 in vitro and in vivo. Furthermore, CK2-mediated phosphorylation…
De-epoxidation of Violaxanthin after Reconstitution into Different Carotenoid Binding Sites of Light-harvesting Complex II
2001
In higher plants, the de-epoxidation of violaxanthin (Vx) to antheraxanthin and zeaxanthin is required for the pH-dependent dissipation of excess light energy as heat and by that process plays an important role in the protection against photo-oxidative damage. The de-epoxidation reaction was investigated in an in vitro system using reconstituted light-harvesting complex II (LHCII) and a thylakoid raw extract enriched in the enzyme Vx de-epoxidase. Reconstitution of LHCII with varying carotenoids was performed to replace lutein and/or neoxanthin, which are bound to the native complex, by Vx. Recombinant LHCII containing either 2 lutein and 1 Vx or 1.6 Vx and 1.1 neoxanthin or 2.8 Vx per mono…
Arsenite-induced aneuploidy following short and long-term exposure in mammalian cells
2009
We studied the long-term progression of chromosomal instability in V79 cells treated acutely with arsenite (10mM, 24 hr) followed by growth in arsenic-free medium for 120 cell generations. Indirect immunostaining using anti-ß-tubulin antibody showed severe alterations in spindle morphology after only 6 h treatment and cytogenetic investigations carried out at the end of treatment revealed that the percentage of cells with 21 chromosomes (modal number of the cell line) decreased, making way for aneuploid cells. The acquired instability remained and propagated within the cell population. Moreover, we treated V79-derived G12 cells with sub-lethal doses (0.1-1.0 μM) of arsenite for 10 days foll…
Truncated recombinant light harvesting complex II proteins are substrates for a protein kinase associated with photosystem II core complexes
1998
AbstractPrevious studies directed towards understanding phosphorylation of the chlorophyll a/b binding proteins comprising light harvesting complex II (LHC II) have concentrated on a single phosphorylation site located close to the N-terminus of the mature proteins. Here we show that a series of recombinant pea Lhcb1 proteins, each missing an N-terminal segment including this site, are nevertheless phosphorylated by a protein kinase associated with a photosystem II core complex preparation. An Lhcb1 protein missing the first 58 amino acid residues is not, however, phosphorylated. The results demonstrate that the LHC II proteins are phosphorylated at one or more sites, the implications of wh…
How to select a biosimilar
2013
In the past few years biosimilars have penetrated the market following the expiry of patents of originator variants. This offers the opportunity to apply high-tech protein products at a lower cost. In contrast to small-molecule generics, clinicians and pharmacists have found it difficult to judge the efficacy and safety profiles of complex protein products. In recent years, the European Medicines Agency (EMA) has gained knowledge on assessing comparability between biosimilars and originator products in scientific and legal areas. This article provides an overview of an extensive set of 31 previously drawn biosimilar selection criteria and describes how several of these criteria are covered …