It has been demonstrated that the V protein of @entity7467 virus (NDV) functions as an alpha/beta interferon (IFN-alpha/beta) antagonist (M. S. Park, M. L. Shaw, J. Mu  oz-Jordan, J. F. Cros, T. Nakaya, N. Bouvier, P. Palese, A. Garc  a-Sastre, and C. F. Basler, J. Virol. 77:1501-1511, 2003). We now show that the NDV V protein plays an important role in host range restriction. In order to study V functions in vivo, recombinant NDV (rNDV) mutants, defective in the expression of the V protein, were generated. These rNDV mutants grow poorly in both embryonated @entity1573 eggs and @entity1573 embryo fibroblasts (CEFs) compared to the wild-type (wt) rNDV. However, insertion of the @entity8768 gene of influenza virus A/PR8/34 into the NDV V(-) genome [rNDV V(-)/ @entity8768 ] restores impaired growth to wt levels in embryonated @entity1573 eggs and CEFs. These data indicate that for viruses infecting avian cells, the NDV V protein and the influenza @entity8768 protein are functionally interchangeable, even though there are no sequence similarities between the two proteins. Interestingly, in @entity1 cells, the titer of wt rNDV is 10 times lower than that of rNDV V(-)/ @entity8768 . Correspondingly, the level of IFN secreted by @entity1 cells infected with wt rNDV is much higher than that secreted by cells infected with the @entity8768 -expressing rNDV. This suggests that the IFN antagonist activity of the NDV V protein is species specific. Finally, the NDV V protein plays an important role in preventing apoptosis in a species-specific manner. The rNDV defective in V induces apoptotic cell death more rapidly in CEFs than does wt rNDV. Taken together, these data suggest that the host range of NDV is limited by the ability of its V protein to efficiently prevent innate host defenses, such as the IFN response and apoptosis.

XXXX virus V protein is a determinant of host range restriction.

@entity7467 :: ('MESH:D009521', 'Disease') :: ['Newcastle disease'] @entity1573 :: ('9031', 'Species') :: ['chicken'] @entity1 :: ('9606', 'Species') :: ['human'] @entity8768 :: ('10625', 'Gene') :: ['NS1']
@entity7467 :: (MESH:D009521,Disease) :: ['Newcastle disease']
