Transgenic tobacco plants that overproduce luciferase (Luc) frequently exhibit post-transcriptional gene silencing (PTGS) of luc. The silencing was observed over five generations and found not to be inherited but acquired by the next generation at a certain frequency. Luc imaging analysis of silenced plants revealed Luc activity only in proliferating tissues such as shoot meristem and developin...

Despite research efforts, cell uptake processes determining siRNA silencing efficiency remain unclear. Here, we examine the relationship between in vitro cell culture models, cellular trafficking and siRNA silencing efficiency to provide a mechanistic insight on siRNA delivery system design. Model siRNApolyplexes, based on chitosan as a ‘classical’ condensing agent, were applied to a panel of l...

In budding yeast, the telomeric DNA is flanked by a combination of two subtelomeric repetitive sequences, the X and Y' elements. We have investigated the influence of these sequences on telomeric silencing. The telomere-proximal portion of either X or Y' dampened silencing when located between the telomere and the reporter gene. These elements were named STARs, for subtelomeric anti-silencing r...

The RNA silencing pathway mediated by small interfering RNAs (siRNAs) plays an important antiviral role in eukaryotes. To counteract this defense barrier, a large number of plant viruses express proteins with RNA silencing suppression activity. Recently, it was reported that the ipomovirus Cucumber vein yellowing virus (CVYV), which lacks the typical silencing suppressor of members of the famil...

A silencing vector for cotton (Gossypium hirsutum) was developed from the geminivirus Cotton leaf crumple virus (CLCrV). The CLCrV coat protein gene was replaced by up to 500 bp of DNA homologous to one of two endogenous genes, the magnesium chelatase subunit I gene (ChlI) or the phytoene desaturase gene (PDS). Cotyledons of cotton cultivar ‘Deltapine 5415’ bombarded with the modified viral vec...

The PI3K/AKT/mTOR pathway is commonly over activated in glioblastoma (GBM), and Rictor was shown to be an important regulator downstream of this pathway. EGFR overexpression is also frequently found in GBM tumors, and both EGFR and Rictor are associated with increased proliferation, invasion, metastasis and poor prognosis. This research evaluated in vitro and in vivo whether the combined silenc...

In plants, small interfering RNAs (siRNAs) and microRNAs (miRNAs) are effectors of RNA silencing, a process involved in defense through RNA interference (RNAi) and in development. Plant viruses are natural targets of RNA silencing, and as a counterdefensive strategy, they have evolved highly diverse silencing suppressor proteins. Although viral suppressors are usually thought to act at distinct...

Purpose: Src is an attractive target because it is overexpressed in a number of malignancies, including ovarian cancer. However, the effect of Src silencing on other Src family kinases (SFKs) is not known. We hypothesized that other SFK members could compensate for the lack of Src activity. Experimental Design: Cell viability after either Src or Fgr silencing was examined in ovarian cancer cell...

ABSTRACT Virus-induced gene silencing (VIGS) is a powerful gene-silencing tool that has been intensively applied in plants. To data, the application of VIGS rubber tree not yet reported. In this study, we described efficient by VIGS. The encoding Hevea brasiliensis phytoene desaturase (HbPDS) was identified genome. Small interfering RNAs from HbPDS and fragment were predicted length 399 bp sele...