Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.31.1 (micrococcal nuclease)
 2,818 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The properties of latent herpesvirus of turkey (HVT) and Marek's disease virus (MDV) genomes have been studied in virus-non-producer MDCC-BO1(T) cells, a T-lymphoblastoid cell line derived from spleen cells of an HVT-vaccinated chicken. The numbers of the two virus genomes in BO1(T) cells remained stable at 1.6 to 1.8 HVT genome equivalents/cell and 3.4 to 3.8 MDV genome equivalents/cell throughout a number of passages and were not decreased by the presence of phosphonoacetic acid in the culture. When the culture temperature of the MDV-producer MDCC-MSB1 cell line was shifted from 41 to 37 degrees C, the cells cultured at 37 degrees C contained about five times as many virus genomes as those cultured at 41 degrees C. In contrast, the numbers of the two virus genomes in BO1(T) cells were not increased by culture at 37 degrees C. RNA extracted from BO1(T) whole cells and from the polyribosomal fraction hybridized to both MDV and HVT DNAs, indicating the expression of both latent virus genomes. Digestion of cell nuclei with micrococcal nuclease revealed that both latent HVT and MDV genomes possess a nucleosomal structure. Closed circular MDV DNA was demonstrated in BO1(T) by isopycnic centrifugation of DNA in ethidium-bromide-CsCl gradients.
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PMID:Latency of herpesvirus of turkey and Marek's disease virus genomes in a chicken T-lymphoblastoid cell line. 626 38

Methods for the isolation of DNA from cell-associated herpesviruses have often yielded samples contaminated with host cellular DNA. Because 2nd and 3rd generation nucleotide sequencers do not rely on molecular cloning of viral DNA, there is a need to develop methods for isolating highly pure DNA from these viruses. The cell-associated alphaherpesvirus Marek's disease virus (MDV-1) was chosen as a test virus for the development of such methodologies. The genomes of six MDV-1 strains have previously been sequenced using both Sanger dideoxy sequencing and 454 Life Sciences pyrosequencing. These genomes largely represent cell culture adapted strains due to the difficulty in obtaining large quantities of DNA from true low passage isolates. There are clear advantages in analyzing MDV-1 virus taken directly from infected tissues or low passage isolates since serial passage attenuates the virus. Procedures using an ATP-dependent exonuclease and Phi29 DNA polymerase to degrade host DNA selectively and amplify MDV-1 DNA enzymatically from total DNA preps were attempted without much success. Ultimately, however, a protocol was developed for purification of low passage MDV-1 DNA from infected avian fibroblasts. The method builds upon and extends available protocols based on hypotonic lysis to release virus particles followed by micrococcal nuclease treatment to degrade cellular DNA. Intact high-molecular weight viral DNA is purified away from an excess of degraded cellular DNA using polyethylene glycol precipitation. 454-based pyrosequencing of viral DNA purified in this manner has generated data containing as little as 2.3% host sequence. On average, DNA preparations were 70% (+/-20%) pure yielding a genome coverage range of 25-74-fold.
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PMID:Purification of DNA from the cell-associated herpesvirus Marek's disease virus for 454 pyrosequencing using micrococcal nuclease digestion and polyethylene glycol precipitation. 1910 24