• The replicase of Cucumber necrosis virus (CNV), a tombusvirus, contains the viral p33 and p92 replication proteins and possible host factors. (uky.edu)
  • To define cis-acting viral RNA sequences that stimulate replicase assembly, we performed a systematic deletion approach with a model tombusvirus replicon RNA in Saccharomyces cerevisiae, which also coexpressed p33 and p92 replication proteins. (uky.edu)
  • The co-opted host proteins likely affect several steps in viral RNA replication, including the assembly of the replicase complex and/or viral RNA synthesis. (prolekarniky.cz)
  • Tomato bushy stunt virus (TBSV), a tombusvirus with a non-segmented, plus-stranded RNA genome, codes for p33 and p92 replicase proteins. (uky.edu)
  • The replicase proteins p33 and p92 of Cymbidium ringspot virus (CymRSV) were found to support the replication of defective interfering (DI) RNA in Saccharomyces cerevisiae cells. (microbiologyresearch.org)
  • Double-labelled immunofluorescence showed that both p33 and p92 replicase proteins localized to peroxisomes, independently of one another and of the presence of the replication template. (microbiologyresearch.org)
  • We have therefore tested the DCL4 functionality in processing exogenous dsRNA-like substrates, such as a replicase-assisted viral replicon defective-interfering RNA and RNA hairpin substrates, or endogenous antisense transcripts. (biomedcentral.com)
  • Conversely, DCL4 did not efficiently process a replicase-assisted viral replicon in vivo, providing evidence that viral RNAs are not accessible to DCL4 in membranes associated in active replication. (biomedcentral.com)
  • Plus-strand RNA virus replication requires the assembly of the viral replicase complexes on intracellular membranes in the host cells. (uky.edu)
  • In vitro replicase assays performed with purified CNV replicase preparations from yeast revealed critical roles for three RNA elements in CNV replicase assembly: the internal p33 recognition element (p33RE), the replication silencer element (RSE), and the 3′-terminal minus-strand initiation promoter (gPR). (uky.edu)
  • Altogether, the role of multiple RNA elements in tombusvirus replicase assembly could be an important factor to ensure fidelity of template selection during replication. (uky.edu)
  • In virology, the tombusvirus internal replication element (IRE) is a segment of RNA located within the region coding for p92 polymerase. (wikipedia.org)
  • specifically, it is thought to be required at an early stage of replication, such as template recruitment and/or replicase complex assembly. (wikipedia.org)
  • Mutations in either p33 or p92 within the short regions involved in p33:p33 and p33:p92 interactions decreased the replication of a TBSV defective interfering RNA in yeast, a model host, supporting the significance of these protein interactions in tombusvirus replication. (uky.edu)
  • The replication of cymbidium ringspot tombusvirus defective interfering-satellite RNA hybrid molecules. (microbiologyresearch.org)
  • The in vitro data show that Ded1p plays a role in enhancing plus-strand synthesis by the viral replicase. (prolekarniky.cz)
  • In addition, we have developed an in vitro assay for Flock house virus (FHV), a small RNA virus of insects, that also demonstrated positive effect on FHV replicase activity by the added Ded1p helicase. (prolekarniky.cz)
  • In addition, the assembly of CNV replicase is stimulated in the presence of plus-stranded viral RNA (Z. Panaviene et al. (uky.edu)
  • We also find that Ded1p is a component of the tombusvirus replicase complex and Ded1p binds to the 3′-end of the viral minus-stranded RNA. (prolekarniky.cz)
  • After the assembly of the membrane-bound viral replicase complexes (VRC), the viral replicase uses the viral RNA as a template to produce complementary (−)RNA. (prolekarniky.cz)
  • In addition to the primary sequences of gPR, RSE, and p33RE, formation of two alternative structures among these elements may also play a role in replicase assembly. (uky.edu)
  • Deletion or mutagenesis of these elements reduced the activity of the CNV replicase to a minimal level. (uky.edu)
  • 5. The proteasomal Rpn11 metalloprotease suppresses tombusvirus RNA recombination and promotes viral replication via facilitating assembly of the viral replicase complex. (nih.gov)
  • 19. The Glycolytic Pyruvate Kinase Is Recruited Directly into the Viral Replicase Complex to Generate ATP for RNA Synthesis. (nih.gov)
  • The bi-partite genome comprises RNA1 and RNA2, encoding the viral replicase protein A and the viral capsid proteins, respectively ( Venter and Schneemann, 2008 ). (elifesciences.org)
  • 11. Reconstitution of an RNA Virus Replicase in Artificial Giant Unilamellar Vesicles Supports Full Replication and Provides Protection for the Double-Stranded RNA Replication Intermediate. (nih.gov)