Limits...
Analysis of a pair of END+ and END- viruses derived from the same bovine viral diarrhea virus stock reveals the amino acid determinants in Npro responsible for inhibition of type I interferon production.

Kozasa T, Abe Y, Mitsuhashi K, Tamura T, Aoki H, Ishimaru M, Nakamura S, Okamatsu M, Kida H, Sakoda Y - J. Vet. Med. Sci. (2014)

Bottom Line: Reportedly, the amino acid residues in the zinc-binding TRASH motif of N(pro) determine the difference in characteristics between END-phenomenon-positive (END(+)) and END-phenomenon-negative (END(-)) classical swine fever viruses (CSFVs).However, the basic mechanism underlying this function in bovine viral diarrhea virus (BVDV) has not been elucidated from the genomic differences between END(+) and END(-) viruses using reverse genetics till date.The END assay, measurements of induced type I interferon and IRF-3 detection in cells infected with these viruses revealed that the aspartic acid at position 136 in the zinc-binding TRASH motif of N(pro) was required to inhibit the production of type I interferon via the degradation of cellular IRF-3, consistently with CSFV.

View Article: PubMed Central - PubMed

Affiliation: Food Safety and Consumer Affairs Bureau, Ministry of Agriculture, Forestry and Fisheries, Chiyoda-ku, Tokyo 100-8950, Japan.

ABSTRACT
The Exaltation of Newcastle disease virus (END) phenomenon is induced by the inhibition of type I interferon in pestivirus-infected cells in vitro, via proteasomal degradation of cellular interferon regulatory factor (IRF)-3 with the property of the viral autoprotease protein N(pro). Reportedly, the amino acid residues in the zinc-binding TRASH motif of N(pro) determine the difference in characteristics between END-phenomenon-positive (END(+)) and END-phenomenon-negative (END(-)) classical swine fever viruses (CSFVs). However, the basic mechanism underlying this function in bovine viral diarrhea virus (BVDV) has not been elucidated from the genomic differences between END(+) and END(-) viruses using reverse genetics till date. In the present study, comparison of complete genome sequences of a pair of END(+) and END(-) viruses isolated from the same virus stock revealed that there were only four amino acid substitutions (D136G, I2623V, D3148G and D3502Y) between two viruses. Based on these differences, viruses with and without mutations at these positions were generated using reverse genetics. The END assay, measurements of induced type I interferon and IRF-3 detection in cells infected with these viruses revealed that the aspartic acid at position 136 in the zinc-binding TRASH motif of N(pro) was required to inhibit the production of type I interferon via the degradation of cellular IRF-3, consistently with CSFV.

No MeSH data available.


Related in: MedlinePlus

Results of END assays. BFM cells infected with GBK_E+, GBK_E−or the in vitro-rescued viruses were superinfected with Newcastledisease virus (NDV). Cells infected with GBK_E+, vGBK_E+ orvGBK_E+/I2623V; D3148G; D3502Y exhibited distinguishable CPE aftersuperinfection with NDV (END+), whereas those infected withGBK_E−, vGBK_E+/D136G or vGBK_E+/D136G; I2623V;D3148G; D3502Y did not exhibit CPE (END−). Scale bar, 5µm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4478729&req=5

fig_002: Results of END assays. BFM cells infected with GBK_E+, GBK_E−or the in vitro-rescued viruses were superinfected with Newcastledisease virus (NDV). Cells infected with GBK_E+, vGBK_E+ orvGBK_E+/I2623V; D3148G; D3502Y exhibited distinguishable CPE aftersuperinfection with NDV (END+), whereas those infected withGBK_E−, vGBK_E+/D136G or vGBK_E+/D136G; I2623V;D3148G; D3502Y did not exhibit CPE (END−). Scale bar, 5µm.

Mentions: To investigate the biological properties of the mutant viruses, BFM cells were inoculatedwith both the parental GBK_E+ and the in vitro-rescuedvGBK_E+ viruses. The results revealed that both GBK_E+ andvGBK_E+ were ncp (data not shown) and exhibited the END phenomenon(END+) (Fig. 2Fig. 2.


Analysis of a pair of END+ and END- viruses derived from the same bovine viral diarrhea virus stock reveals the amino acid determinants in Npro responsible for inhibition of type I interferon production.

Kozasa T, Abe Y, Mitsuhashi K, Tamura T, Aoki H, Ishimaru M, Nakamura S, Okamatsu M, Kida H, Sakoda Y - J. Vet. Med. Sci. (2014)

Results of END assays. BFM cells infected with GBK_E+, GBK_E−or the in vitro-rescued viruses were superinfected with Newcastledisease virus (NDV). Cells infected with GBK_E+, vGBK_E+ orvGBK_E+/I2623V; D3148G; D3502Y exhibited distinguishable CPE aftersuperinfection with NDV (END+), whereas those infected withGBK_E−, vGBK_E+/D136G or vGBK_E+/D136G; I2623V;D3148G; D3502Y did not exhibit CPE (END−). Scale bar, 5µm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4478729&req=5

fig_002: Results of END assays. BFM cells infected with GBK_E+, GBK_E−or the in vitro-rescued viruses were superinfected with Newcastledisease virus (NDV). Cells infected with GBK_E+, vGBK_E+ orvGBK_E+/I2623V; D3148G; D3502Y exhibited distinguishable CPE aftersuperinfection with NDV (END+), whereas those infected withGBK_E−, vGBK_E+/D136G or vGBK_E+/D136G; I2623V;D3148G; D3502Y did not exhibit CPE (END−). Scale bar, 5µm.
Mentions: To investigate the biological properties of the mutant viruses, BFM cells were inoculatedwith both the parental GBK_E+ and the in vitro-rescuedvGBK_E+ viruses. The results revealed that both GBK_E+ andvGBK_E+ were ncp (data not shown) and exhibited the END phenomenon(END+) (Fig. 2Fig. 2.

Bottom Line: Reportedly, the amino acid residues in the zinc-binding TRASH motif of N(pro) determine the difference in characteristics between END-phenomenon-positive (END(+)) and END-phenomenon-negative (END(-)) classical swine fever viruses (CSFVs).However, the basic mechanism underlying this function in bovine viral diarrhea virus (BVDV) has not been elucidated from the genomic differences between END(+) and END(-) viruses using reverse genetics till date.The END assay, measurements of induced type I interferon and IRF-3 detection in cells infected with these viruses revealed that the aspartic acid at position 136 in the zinc-binding TRASH motif of N(pro) was required to inhibit the production of type I interferon via the degradation of cellular IRF-3, consistently with CSFV.

View Article: PubMed Central - PubMed

Affiliation: Food Safety and Consumer Affairs Bureau, Ministry of Agriculture, Forestry and Fisheries, Chiyoda-ku, Tokyo 100-8950, Japan.

ABSTRACT
The Exaltation of Newcastle disease virus (END) phenomenon is induced by the inhibition of type I interferon in pestivirus-infected cells in vitro, via proteasomal degradation of cellular interferon regulatory factor (IRF)-3 with the property of the viral autoprotease protein N(pro). Reportedly, the amino acid residues in the zinc-binding TRASH motif of N(pro) determine the difference in characteristics between END-phenomenon-positive (END(+)) and END-phenomenon-negative (END(-)) classical swine fever viruses (CSFVs). However, the basic mechanism underlying this function in bovine viral diarrhea virus (BVDV) has not been elucidated from the genomic differences between END(+) and END(-) viruses using reverse genetics till date. In the present study, comparison of complete genome sequences of a pair of END(+) and END(-) viruses isolated from the same virus stock revealed that there were only four amino acid substitutions (D136G, I2623V, D3148G and D3502Y) between two viruses. Based on these differences, viruses with and without mutations at these positions were generated using reverse genetics. The END assay, measurements of induced type I interferon and IRF-3 detection in cells infected with these viruses revealed that the aspartic acid at position 136 in the zinc-binding TRASH motif of N(pro) was required to inhibit the production of type I interferon via the degradation of cellular IRF-3, consistently with CSFV.

No MeSH data available.


Related in: MedlinePlus