Location: Endemic Poultry Viral Diseases Research
Title: Effects of insertion sites in a Newcastle disease virus vector on foreign gene expression through an internal ribosomal entry siteAuthor
Yu, Qingzhong | |
ZHANG, ZHENYU - Northeast Agricultural University | |
ZHAO, WEI - Beijing Centers For Disease And Prevention, Department Of Pest Inspection | |
LI, DESHAN - Northeast Agricultural University | |
YANG, JINLONG - Chongqing Academy Of Animal Sciences | |
Zsak, Laszlo |
Submitted to: International Congress of Virology
Publication Type: Abstract Only Publication Acceptance Date: 5/18/2017 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Newcastle disease virus (NDV), avian paramyxovirus type 1, has been developed as a vector to express foreign genes for vaccine and gene therapy purposes. The foreign genes are usually inserted into a non-coding region of the NDV genome as an independent transcription unit (ITU), which potentially attenuates its downstream gene transcription, and subsequently interfere with virus replication and the level of foreign gene expression. In the present study, we developed a novel approach for foreign gene expression by NDV from a second open reading frame (ORF) through an internal ribosomal entry site (IRES). We generated six NDV LaSota strain-based recombinant viruses vectoring the IRES and a red fluorescence protein (RFP) gene as a 2nd ORF after the coding sequences of the NP, P, M, F, HN, or L gene of NDV using reverse genetics technology. The insertion of the 2nd ORF slightly attenuated the virus pathogenicity, but did not affect virus growth ability. Quantitative measurements of the RFP expression from recombinant virus infected DF-1 cells revealed that the abundance of viral mRNAs containing RFP and the red fluorescence intensity were positively correlated with the gene order of NDV, 3’ NP-P-M-F-HN-L, proving the sequential transcription mechanism on NDV. The results suggested that the level of foreign gene expression could be regulated by selecting the 2nd ORF insertion site relative to the 3’ end of the NDV vector to maximize the efficacy of vaccine and gene therapy. |