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Showing papers by "Richard J. Colonno published in 1994"


Journal ArticleDOI
TL;DR: The herpes simplex virus type 1 protease and related proteins are involved in the assembly of viral capsids and the function of Na, at least in part, is to direct the catalytic domain N(o) to the nucleus.
Abstract: The herpes simplex virus type 1 protease and related proteins are involved in the assembly of viral capsids. The protease encoded by the UL26 gene can process itself and its substrate ICP35, encoded by the UL26.5 gene. To better understand the functions of the protease in infected cells, we have isolated a complementing cell line (BMS-MG22) and constructed and characterized a null UL26 mutant virus, m100. The mutant virus failed to grow on Vero cells and required a complementing cell line for its propagation, confirming that the UL26 gene product is essential for viral growth. Phenotypic analysis of m100 shows that (i) normal amounts of the c and d forms of ICP35 were produced, but they failed to be processed to the cleaved forms, e and f; (ii) viral DNA replication of the mutant proceeded at near wild-type levels, but DNA was not processed to unit length or encapsidated; (iii) capsid structures were observed in thin sections of m100-infected Vero cells by electron microscopy, but assembly of VP5 into hexons of the capsid structure was conformationally altered; and (iv) nuclear localizations of the protease and ICP35 are independent of each other, and the function(s) of Na, at least in part, is to direct the catalytic domain N(o) to the nucleus.

205 citations


Journal ArticleDOI
TL;DR: Mass spectrometric studies and sequencing analysis by Edman degradation identified Ser-129 as the residue modified by DFP and this residue and the region in which it is found is highly conserved among the herpes viral proteases.

63 citations


Journal ArticleDOI
TL;DR: It is shown that a pool of capped oligonucleotides too short to prime transcription, but long enough to bind with high affinity to the viral polymerase, are potent inhibitors of cap-dependent transcription in vitro.
Abstract: A synthetic 67-nt RNA substrate, containing a 32P-labeled cap-1 structure (m7G32pppGm) was specifically cleaved by the influenza virus RNA polymerase (EC 2.7.7.48) to yield a single capped 11-nt fragment capable of directly priming transcription. An analysis of systematic truncations of this RNA substrate demonstrated that an additional nucleotide beyond this cleavage site was required for cleavage. The minimal RNA chain length required for priming activity was found to be 9 nt, while in contrast an RNA chain length of at least 4 nt was required for efficient binding to the viral polymerase. On the basis of these chain length requirements we show that a pool of capped oligonucleotides too short to prime transcription, but long enough to bind with high affinity to the viral polymerase, are potent inhibitors of cap-dependent transcription in vitro.

61 citations