Ye. Chang et al., THE NULL MUTANT OF THE U(L)31 GENE OF HERPES-SIMPLEX VIRUS-1 - CONSTRUCTION AND PHENOTYPE IN INFECTED-CELLS, Journal of virology, 71(11), 1997, pp. 8307-8315
Earlier studies have shown that the U(L)31 protein is homogeneously di
stributed throughout the nucleus and cofractionates with nuclear matri
x, We report the construction from an appropriate cosmid library a del
etion mutant which replicates in rabbit skin cells carrying the U(L)31
gene under a late (gamma(1)) viral promoter, The mutant virus exhibit
s cytopathic effects and yields 0.01 to 0.1% of the yield of wild-type
parent virus in noncomplementing cells but amounts of virus 10- to 1,
000-fold higher than those recovered from the same cells 3 h after inf
ection, Electron microscopic studies indicate the presence of small nu
mbers of full capsids but a lack of enveloped virions, Viral DNA extra
cted from the cytoplasm of infected cells exhibits free termini indica
ting cleavage/packaging of viral DNA from concatemers for packaging in
to virions, but analyses of viral DNAs by pulsed-field electrophoresis
indicate that at 16 h after infection, both the yields of viral DNA a
nd cleavage of viral DNA for packaging are decreased, The repaired vir
us cannot be differentiated from the wild-type parent. These results s
uggest the possibility that U(L)31 protein forms a network to enable t
he anchorage of viral products for the synthesis and/or packaging of v
iral DNA into virions.