TY - JOUR
T1 - African swine fever virus NL gene is not required for virus virulence
AU - Afonso, C. L.
AU - Zsak, L.
AU - Carrillo, C.
AU - Borca, M. V.
AU - Rock, D. L.
PY - 1998/10
Y1 - 1998/10
N2 - Previously, we described a highly conserved nonessential African swine fever virus (ASFV) right variable region gene, NL. Deletion of NL from the European pathogenic isolate E70 resulted in almost complete attenuation of the virus in domestic swine. To study gene function further, NL gene deletion mutants were constructed from two pathogenic African ASFV isolates, Malawi Lil-20/1 (Mal) and Pretoriuskop/96/4 (Pr4). Unexpectedly, both Mal (Mal-ΔNL) and PR4 (Pr4ΔNL) null mutants remained highly virulent when inoculated in swine. Mal-ΔNL exhibited a disease and virulence phenotype indistinguishable from its revertant, Mal-NLR, which caused 100% mortality. Mortality among Pr4ΔNL-infected animals was also high; however, a significant delay in onset of fever and viraemia and in time to death was observed. These data indicate that NL gene function is not required for ASFV virulence and that other yet-to-be identified viral determinants perform significant virulence functions in these African field isolates.
AB - Previously, we described a highly conserved nonessential African swine fever virus (ASFV) right variable region gene, NL. Deletion of NL from the European pathogenic isolate E70 resulted in almost complete attenuation of the virus in domestic swine. To study gene function further, NL gene deletion mutants were constructed from two pathogenic African ASFV isolates, Malawi Lil-20/1 (Mal) and Pretoriuskop/96/4 (Pr4). Unexpectedly, both Mal (Mal-ΔNL) and PR4 (Pr4ΔNL) null mutants remained highly virulent when inoculated in swine. Mal-ΔNL exhibited a disease and virulence phenotype indistinguishable from its revertant, Mal-NLR, which caused 100% mortality. Mortality among Pr4ΔNL-infected animals was also high; however, a significant delay in onset of fever and viraemia and in time to death was observed. These data indicate that NL gene function is not required for ASFV virulence and that other yet-to-be identified viral determinants perform significant virulence functions in these African field isolates.
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U2 - 10.1099/0022-1317-79-10-2543
DO - 10.1099/0022-1317-79-10-2543
M3 - Article
C2 - 9780062
AN - SCOPUS:0031661195
SN - 0022-1317
VL - 79
SP - 2543
EP - 2547
JO - Journal of General Virology
JF - Journal of General Virology
IS - 10
ER -