Cytomegalovirus (CMV) is a nearly ubiquitous but usually asymptomatic human pathogen in adults. However, primary infections neonatally, or of a fetus during pregnancy, often produces serious CNS sequelae. Reactivated infections are also a major cause of morbidity in AIDS patients and bone marrow, renal and heart transplant patients. The nucleotide analogue ganciclovir (DHPG) is the only effective therapeutic agent available at present to combat severe CMV infections, although its usefulness is limited. DNA viruses provide useful and important model systems for basic research into mechanisms of gene regulation and DNA synthesis in mammalian cells. CKV is the largest and most complex of human viruses. However, a comprehensive picture of the genetic structure of human CMV has recently become available as a result of the complete determination of the DNA sequence of its 229-kb genome. Consequently, many new insights into the molecular biology and pathogenicity of the virus are expected within the next few years. In situ hybridization procedures are also beginning to yield new information about the sites of persistent and latent infection and the extent of viral gene expression in vivo. We have recently identified a lytic cycle DNA replication origin (ori-U) in the unique L-segment of human and simian CMV genomes by a novel procedure using DHPG-induced chain termination. Using this information and a transient DNA-transfection system developed for identifying the essential replication genes in HSV and EBV, we propose to (1) Examine the structure and directionality of replicating HCMV DNA growth forks in the presence and absence of DHPG; (2) Further define and characterize essential cis-acting elements and cellular factor DNA-binding sites within ori-U; (3) Identify all of the HCMV genes required to replicate ori-U by transient cotransfection assays; (4) Ask whether HCMV encodes a unique origin-specific DNA-binding protein and define its consensus sequence recognition properties.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
1R01AI031454-01A1
Application #
3146462
Study Section
Experimental Virology Study Section (EVR)
Project Start
1992-03-01
Project End
1997-02-28
Budget Start
1992-03-01
Budget End
1993-02-28
Support Year
1
Fiscal Year
1992
Total Cost
Indirect Cost
Name
Johns Hopkins University
Department
Type
Schools of Medicine
DUNS #
045911138
City
Baltimore
State
MD
Country
United States
Zip Code
21218
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