The capsid protein of feline calicivirus (FCV) was expressed by using plasmids containing cytomegalovirus, simian virus 40, or T7 promoters. The strongest expression was achieved with the T7 promoter and coinfection with vaccinia virus expressing the T7 RNA polymerase (MVA/T7pol). The FCV precursor capsid protein was processed to the mature-size protein, and these proteins were assembled in to ...

Bacteriophage T7 bearing amber mutations in both gene 1.3 (T7 DNA ligase) and gene 3 (T7 endonuclease I) are viable when grown in suppressor-negative, ligase-negative hosts. This is evidenced by a high plating efficiency and a large burst size compared to the single mutants. These findings may be explained by a limited destruction of cellular DNA by the double mutant.

S ynthetic gene circuits have become an invaluable tool for studying the design principles of native gene networks and facilitating new biotechnologies (Way et al, 2014). Synthetic biologists often strive to build circuits within a framework that enables their consistent and robust operation across a range of hosts and conditions. Currently, however, each circuit must be fastidiously tuned and ...

A mouse cell line that constitutively synthesizes the bacteriophage T7 RNA polymerase was constructed. Fluorescence microscopy indicated that the T7 RNA polymerase was present in the cytoplasmic compartment. The system provided, therefore, a unique opportunity to study structural elements of mRNA that affect stability and translation. The in vivo activity of the bacteriophage polymerase was dem...

The helicase and primase activities of bacteriophage T7 are distributed between the 56- and 63-kDa gene 4 proteins. The 56-kDa gene 4 protein lacks 63 amino acids found at the N terminus of the colinear 63-kDa protein and catalyzes helicase activity. The 63-kDa gene 4 protein catalyzes both primase and helicase activities. A bacteriophage deleted for gene 4, T7 delta 4-1, has been tested for gr...

Experiments in a number of different systems have suggested that the initiation of DNA replication is often dependent upon transcription at the origin of replication. During infection with bacteriophage T7, the T7 genome is transcribed first by the bacterial RNA polymerase and then by a phage-coded enzyme, the product of gene 1. The bacterial enzyme does not appear to be directly involved in th...

During nonpermissive infection by a T7 amber mutant in gene 1 (phage RNA polymerase-deficient), synthesis of the products of the phage genes 3 (endonuclease), 3, 5 (lysozyme), 5 (DNA polymerase), and 17 (serum blocking power) was shown to occur at about half the rate as during wild-type infection. This relatively high rate of expression of "late" genes (transcribed normally by the phage RNA pol...

Non-viral vectors are promising vehicles for gene therapy but delivery of plasmid DNA to post-mitotic cells is challenging as nuclear entry is particularly inefficient. We have developed and evaluated a hybrid mRNA/DNA system designed to bypass the nuclear barrier to transfection and facilitate cytoplasmic gene expression. This system, based on co-delivery of mRNA(A64) encoding for T7 RNA polym...