Histone deacetylase 3, not histone deacetylase 2, interacts with the major immediate early locus of human cytomegalovirus.
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ABSTRACT:
SUBMITTER: Huang Y
PROVIDER: S-EPMC3077330 | biostudies-other | 2011 Mar
REPOSITORIES: biostudies-other
Publications
Histone deacetylase 3, not histone deacetylase 2, interacts with the major immediate early locus of human cytomegalovirus.
Huang Ying Y Tang Qiyi Q Nguyen Michael M Dulal Kalpana K Wang Weijia W Zhu Hua H
Virology journal 20110331
Evidence suggests that genome chromatinization and the posttranslational modification of histones are involved in the regulation of viral gene expression, including the human cytomegalovirus (HCMV). We performed a ChIP-on-Chip assay to determine whether histone deacetylases (HDACs) interact with HCMV genomic DNA on a global level. Surprisingly, we found that HDAC3, but not HDAC2, interacts not only with the major immediate early (MIE) promoter but also with the entire MIE locus, suggesting a het ...[more]
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Project description:Human cytomegalovirus (HCMV) has been shown to have the potential to alter cellular gene expression early after infection. However, one-gene approaches and the use of closed system gene expression technologies have identified only few cellular genes whose activity changed immediate-early. We therefore used serial analysis of gene expression (SAGE) to investigate the transcriptional program of human fibroblasts in response to HCMV in the immediate-early phase of infection. Differential expression of various cellular genes was monitored. Transcriptional expression changes of genes coding for ribosomal proteins reflected a general cellular response to starvation and stress. But differential regulation of genes coding for transcription factors and proteins associated with cellular metabolism, homeostasis and cell structure may represent transcriptional alterations in response to HCMV infection. Expression kinetics by 5' nuclease fluorigenic real-time PCR of selected genes revealed partial protection of infected cells against initial stress-associated alterations of gene expression and indicated fluctuations of transcriptional levels over time. Additionally, agreement with the quantitative results obtained by SAGE was observed only for genes up-regulated in HCMV-infected cells. This finding pointed to various technical and statistical parameters that all may be critical for quantitative transcriptome studies using global approaches, especially when exploring biological systems in a critical phase of cellular physiology. Keywords: other
2003-07-16 | GSE506 | GEO
Project description:Human cytomegalovirus (HCMV) has been shown to have the potential to alter cellular gene expression early after infection. However, one-gene approaches and the use of closed system gene expression technologies have identified only few cellular genes whose activity changed immediate-early. We therefore used serial analysis of gene expression (SAGE) to investigate the transcriptional program of human fibroblasts in response to HCMV in the immediate-early phase of infection. Differential expression of various cellular genes was monitored. Transcriptional expression changes of genes coding for ribosomal proteins reflected a general cellular response to starvation and stress. But differential regulation of genes coding for transcription factors and proteins associated with cellular metabolism, homeostasis and cell structure may represent transcriptional alterations in response to HCMV infection. Expression kinetics by 5' nuclease fluorigenic real-time PCR of selected genes revealed partial protection of infected cells against initial stress-associated alterations of gene expression and indicated fluctuations of transcriptional levels over time. Additionally, agreement with the quantitative results obtained by SAGE was observed only for genes up-regulated in HCMV-infected cells. This finding pointed to various technical and statistical parameters that all may be critical for quantitative transcriptome studies using global approaches, especially when exploring biological systems in a critical phase of cellular physiology. Keywords: other
2003-07-16 | E-GEOD-506 | biostudies-arrayexpress
Project description:The region of the human cytomegalovirus (CMV) genome between the UL127 open reading frame and the major immediate-early (MIE) enhancer is referred to as the unique region. DNase I protection analysis with human cell nuclear extracts demonstrated multiple protein binding sites in this region of the viral genome (P. Ghazal, H. Lubon, C. Reynolds-Kohler, L. Hennighausen, and J. A. Nelson, Virology 174:18-25, 1990). However, the function of this region in the context of the viral genome is not known. In wild-type human CMV-infected human fibroblasts, cells permissive for viral replication, there is little to no transcription from UL127. We determined that the unique region prevented transcription from the UL127 promoter but had no effect on the divergent MIE promoter. In transient-transfection assays, the basal level of expression from the UL127 promoter increased significantly when the wild-type unique sequences were mutated. In recombinant viruses with similar mutations in the unique region, expression from the UL127 promoter occurred only after de novo viral protein synthesis, typical of an early viral promoter. A 111-bp deletion-substitution of the unique sequence caused approximately a 20-fold increase in the steady-state level of RNA from the UL127 promoter and a 245-fold increase in the expression of a downstream indicator gene. This viral negative regulatory region was also mutated at approximately 50-bp regions proximal and distal to the UL127 promoter. Although some repressive effects were detected in the distal region, mutations of the region proximal to the UL127 promoter had the most significant effects on transcription. Within the proximal and distal regions, there are potential cis sites for known eucaryotic transcriptional repressor proteins. This region may also bind unknown viral proteins. We propose that the unique region upstream of the UL127 promoter and the MIE enhancer negatively regulates the expression from the UL127 promoter in permissive human fibroblast cells. This region may be a regulatory boundary preventing the effects of the very strong MIE enhancer on this promoter.
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