Authors: Wei Zhao Haixia Hu Laszlo Zsak Qingzhong Yu Zengqi Yang
Publish Date: 2013/04/03
Volume: 47, Issue: 1, Pages: 27-33
Abstract
The hemagglutininneuraminidase HN protein of Newcastle disease virus NDV plays an important role in virus pathogenicity and tissue tropism Sequence analysis revealed that the HN gene of many asymptomatic enteric NDV strains encodes a larger open reading frame 616 amino acids aa with additional 39 aa at its Cterminus when compared with that 577 aa of respirotropic NDV strains Therefore it has been suspected that the HN Cterminal extension may contribute to the enteric tropism In the present study we generated a NDV respirotropic strain LaSotabased recombinant virus with a HN Cterminal extension of 39 aa derived from an enterotropic NDV strain using reverse genetics technology The biological characterization of the recombinant virus rLSHNex showed that the HN Cterminal extension slightly attenuated the virus pathogenicity in embryonated eggs and in dayold chicks when compared to the parental LaSota virus However the HN Cterminal extension did not alter virus tissue tropism In infected chickens the recombinant virus was detected and reisolated from the tracheal tissue but not from the intestinal tissue exhibiting a similar respirotropic tissue preference as its parental LaSota strain These results demonstrated that the HN protein Cterminal extension of NDV is not the determinant of the virus enteric tropismThe authors wish to thank Xiuqin Xia and Fenglan Li for excellent technical assistance Patti Miller for critical review and the SEPRL sequencing facility personnel for nucleotide sequencing W Zhao and H Hu were sponsored by a scholarship from China Scholarship Council This research was supported by USDA ARS CRIS Project 66123200006700D
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