Disease relevance of D4R

• Each mutated D4R gene was transfected into vaccinia virus ts4149-infected cells in order to assess the recombination events that allowed virus survival at 40 degrees C. Genetic analysis and sequencing studies revealed that the only viruses to survive were those in which recombination eliminated the mutant locus [1].
• Thus, the complementing host cells allowed the rescue of a virus defective in the D4R gene, demonstrating that this system may be used for the propagation of defective cytoplasmic DNA viruses [2].
• The SFV BamHI D6R open reading frame and the homologous HindIII D4R open reading frame from the Orthopoxvirus vaccinia virus were cloned under the regulation of a phage T7 promoter and expressed in Escherichia coli as insoluble high-molecular-weight aggregates [3].
• The D4R gene belongs to the group of early transcribed vaccinia genes preventing a virus defective in D4R from entering into the intermediate and late phase of replication under noncomplementing conditions [4].

High impact information on D4R

• Moreover, no viral DNA synthesis was detected when cells were infected with either stringent mutant at 39 degrees C. The previous yeast two-hybrid analysis together with the present characterization of A20R temperature-sensitive mutants suggested that the A20R, D4R, and D5R proteins are components of a multiprotein DNA replication complex [5].
• The temperature-sensitive vaccinia virus mutant ts4149, which maps within D4R, was able to grow under restrictive conditions in both of these transformed cell lines [2].
• Cell clones complemented D4R function to various degrees, demonstrating complementation of an essential vaccinia virus gene by a cell line constitutively expressing the essential function [2].
• Recombinant VV based on a D4R-defective parental strain expressing cDNAs coding for the human blood coagulation factors VII and XI produced significantly more recombinant protein than the corresponding recombinants based on wild-type VV [4].

Chemical compound and disease context of D4R

• We conclude that the uracil cleavage activity of the D4R protein is essential for its function in vaccinia virus DNA replication, suggesting that the removal of uracil residues plays an obligatory role [1].

References