In eukaryotes, the nuclear ribosomal DNA (rDNA) is the source of the structural 18S, 5.8S and 25S rRNAs. In hemiascomycetous yeasts, the 25S rDNA sequence was described to lodge an antisense open reading frame (ORF) named TAR1 for Transcript Antisense to Ribosomal RNA. Here, we present the first immuno-detection and sub-cellular localization of the authentic product of this atypical yeast gene....

F-like plasmid transfer is mediated by the FinOP fertility inhibition system. Expression of the F positive regulatory protein, TraJ, is controlled by the action of the antisense RNA, FinP, and the RNA-binding protein FinO. FinO binds to and protects FinP from degradation and promotes duplex formation between FinP and traJ mRNA, leading to repression of both traJ expression and conjugative F tra...

We have devised and constructed a biological containment system designed to cause programmed bacterial cell lysis with no survivors. We have validated this system, using Salmonella enterica serovar Typhimurium vaccines for antigen delivery after colonization of host lymphoid tissues. The system is composed of two parts. The first component is Salmonella typhimurium strain chi8937, with deletion...

Although matrix metalloproteinases (MMPs) are thought to be involved in the invasion and metastasis of a variety of malignant tumors, including human hepatocellular carcinoma (HCC), the mechanisms for the expression of MMPs in HCC are not known. To understand the mechanism(s) of MMP expression, the expression of matrilysin (MMP-7) and several genes of the Ets transcription factor family was inv...

Programmed cell death by the hok/sok locus of plasmid R1 relies on a complex translational control mechanism. The highly stable hok mRNA is activated by 3'-end exonucleolytical processing. Removal of the mRNA 3' end releases a 5'-end sequence that triggers refolding of the mRNA. The refolded hok mRNA is translatable but can also bind the inhibitory Sok antisense RNA. Binding of Sok RNA leads to...

Antisense RNA transcription attenuators are a key component of the synthetic biology toolbox, with their ability to serve as building blocks for both signal integration logic circuits and transcriptional cascades. However, a central challenge to building more sophisticated RNA genetic circuitry is creating larger families of orthogonal attenuators that function independently of each other. Here...

The accumulation of PrP(Sc) in scrapie-infected neuronal cells has been prevented by three approaches: (i) transfection of ScMNB cells with an antisense laminin receptor precursor (LRP) RNA-expression plasmid, (ii) transfection of ScN2a cells and ScGT1 cells with small interfering RNAs (siRNAs) specific for the LRP mRNA, and (iii) incubation of ScN2a cells with an anti-LRP/LR antibody. LRP anti...

BALB/c3T3 cells are exquisitely growth regulated and require both platelet-derived growth factor and insulin-like growth factor-1 (IGF-1) for optimal proliferation. BALB/c3T3 cells that constitutively express IGF-1 and elevated levels of IGF-1 receptor (IGF-1R) are capable of growth in serum-free medium without the addition of any exogenous growth factors. BALB/c3T3 cells overexpressing only th...

Cell specific gene silencing effects of antisense oligodeoxynucleotide (AS-ODN), synthetic small interfering RNA (siRNA-S), and siRNA expressing plasmid (siRNA-P) were comparatively evaluated. Poly(ethylenimine) (PEI) and PEI-graft-poly(ethylene glycol)-folate (PEI-PEG-FOL) conjugate were used to form nanosized polyelectrolyte complexes with the above three nucleic acids coding for inhibition o...

Down-regulation of Myc expression is the earliest documented change in gene expression in retinoic acid-induced differentiation of murine F9 teratocarcinoma cells. F9 cells transfected with plasmids expressing antisense Myc sequences under control of the simian virus 40 (SV40) early promoter exhibit a decrease in Myc protein. The result of this decrease is the spontaneous differentiation into c...