Disease relevance of virG

• virG, an Agrobacterium tumefaciens transcriptional activator, initiates translation at a UUG codon and is a sequence-specific DNA-binding protein [1].
• The two forms of RNAP were equally efficient in transcription from a sigma(70)-dependent E. coli galP1 promoter; however, only the hybrid RNAP was able to transcribe virBp in a virG-dependent manner [2].

High impact information on virG

• However, virA and virG are insufficient to activate transcription from virulence gene promoters within Escherichia coli cells, indicating a requirement for additional A. tumefaciens genes [2].
• In order to increase the efficiency of transfer of unusually large BIBAC T-DNAs, helper plasmids that carry additional copies of A. tumefaciens virulence genes virG and virE were constructed [3].
• Insertional and deoxyoligonucleotide-directed mutagenesis studies showed that both octopine and nopaline Ti plasmid virG genes initiate translation at a UUG codon [1].
• The TTG codon preceded by an SD sequence and a T signal is also conserved in the virG sequences from other three tumor-inducing plasmids previously reported [4].
• The nucleotide sequence of the virG gene for a transcriptional activator on the agropine-type hairy-root-inducing plasmid pRiA4 was determined [4].

Chemical compound and disease context of virG

• Agrobacterium cells containing this gene fusion showed a large increase in virG activity in the presence of virA and acetosyringone [1].

Biological context of virG

• The processes of transgene integration and transgene expression were suppressed when Agrobacteria contained mutated virA, virB or virG genes, suggesting that Agrobacterium transforms sea urchin cells by a mechanism similar to that which mediates T-DNA transfer to plants [5].

Associations of virG with chemical compounds

• Since the trp promoter is not under virA-virG control, this result indicates that modification of VirG is necessary for its full activity [1].
• As on nopaline pTiC58, fragments bearing the homologies with virC and virG are closer together on both pRi than on octopine pTiAch5 [6].

Other interactions of virG

• Several variables affecting transformation efficiency were examined including insert size, Agrobacterium genetic background, and the presence of additional copies of the virG, virE1 and virE2 genes [7].

References