Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.1.21 (thymidine kinase)
 7,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The spread of herpes simplex virus type 1 (HSV-1) strain KOS, and two less neurovirulent mutants of the strain was studied in female DBA/2 mice during the 1- to 5-day postinoculation period after intracerebral inoculation. Immunohistopathology showed that wild-type KOS virus first infected the meninges and ependymal cells but did not infect cells at the inoculation sites. The virus continued to spread to some cells directly adjacent to ventricles; however, the most extensive and severe lesions were found in the pyriform lobes and other structures associated with the limbic system. The pattern of spread suggested that direct cell to cell viral spread is important but that retrograde axonal transport to distant sites probably accounts for the more severe lesions associated with the limbic system. Both less neurovirulent mutant viruses multiplied to a much lesser degree in the brain and spread less extensively than the wild type virus when equivalent doses were given; however, when a large dose of the least neurovirulent mar C10.1 mutant virus was inoculated, infection spread rapidly to the same regions of the brain affected by KOS. Studies of mar C10.1 showed that thymidine kinase deficiency, rather than a mutation in the gene coding for glycoprotein C, probably accounted for the decreased neurovirulence of this mutant. This mouse model of HSV-1 virus-induced encephalitis, in combination with appropriate studies of the molecular biology of the HSV-1 KOS strain, should be useful for the study of neurovirulence factors contributing to the pathogenesis of HSV-1.
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PMID:Characterization of encephalitis in adult mice induced by intracerebral inoculation of herpes simplex virus type 1 (KOS) and comparison with mutants showing decreased virulence. 254 66

To study the expression of SV40 tsA genomes that had been non-selectively introduced into mouse cells, SV40 tsA207 DNA was cleaved with BamH I and ligated to BamH I-cleaved plasmid pAGO DNA, which contains a functional HSV-1 thymidine kinase (TK) gene in the form of 2 kbp Pvu II fragment inserted at the Pvu II site of pBR322. Recombinant plasmids (11-12 kbp) were isolated and amplified in E. coli K12 strain RRI. Restriction nuclease analyses demonstrated that recombinant plasmids pSB15 and pSB10 contained intact SV40 genomes with the polarity of transcription oriented in the same direction (clockwise) or the opposite direction (counterclockwise), respectively, in relation to that of the HSV-1 TK gene. Cla I-cleaved pSB10 and pSB15 DNAs were used to transform LM(TK-) cells to TK+. Serological and disc PAGE analyses showed that clonal lines transformed by these plasmids all expressed the selected marker, HSV-1 TK. Molecular hybridization experiments showed that transformed clonal lines TF pSB10 C7 and TF pSB15 C10 had integrated intact SV40 genomes at one integration site, TF pSB10 C3 had integrated an SV40 genome with a small deletion near the BamH I site, but TF pSB15 Cl had integrated a plasmid from which most of the SV40 nucleotide sequences had been deleted. IF assays with hamster anti-SV40 tumor sera showed that TF pSB10 C7 and TF pSB15 C10 strongly expressed SV40 T antigens in over 90% of the cells, TF pSB10 C3 expressed SV40 T antigens in a minority of the cells, and TF pSB15 C1 did not express SV40 T antigens at all. [35S]-methionine labelling and immunoprecipitation experiments showed that, at 36.5 degrees C: (1) TF pSB10 C7 and TF pSB15 C10 expressed 92K and 20K mol. wt. species of SV40 T antigens and 50-55K cellular protein; (2) expression of all three was reduced in TF pSB10 C3 cells; and (3) TF pSB15 C1 expressed none of the SV40 T antigens, nor did parental LM(TK-) or TF 8-2 transformed cells (which contained the HSV-1 TK gene but not SV40 DNA). At 40 degrees C, labelling of the 50-55K cellular protein was markedly reduced in TF pSB10 C7 and pSB15 C10 cells. The results suggest that SV40 large T antigen (92K) induces and/or stabilizes the 50-55K cellular protein in these mouse cells.
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PMID:Expression of SV40 T antigen polypeptides in cells biochemically transformed by plasmids containing the herpes simplex virus thymidine kinase gene and the genome of an SV40tsA mutant. 627 34