The J gene of bacteriophage phi X174: in vitro analysis of J protein function.
The J protein of phi X174 is a small, highly basic protein and is a component of the phage capsid. We have investigated the role of J protein during single-stranded viral DNA synthesis and phage morphogenesis by using an in vitro system composed of purified viral and host components (Aoyama et al., Proc. Natl. Acad. Sci. U.S.A. 80:4195-4199, 1983). The characterization of the products made in the presence and absence of J protein shows that J protein is not required for viral DNA synthesis, but is required for the packaging of DNA into infectious phage. The ability of J protein to bind to double-stranded DNA as well as single-stranded DNA and other interactions with DNA suggest a model in which J protein binds to double-stranded, replicative form DNA and enters the phage prohead by remaining bound to viral DNA as it is encapsidated.
Hamatake
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Aoyama
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Hayashi
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D000251:Adenosine Triphosphatases / Q000494:pharmacology; D010584:Bacteriophage phi X 174 / Q000235:genetics*; D004265:DNA Helicases; D004279:DNA, Viral / Q000032:analysis / Q000096:biosynthesis; D004259:DNA-Directed DNA Polymerase / Q000494:pharmacology; D005814:Genes, Viral; D014764:Viral Proteins / Q000502:physiology*
D004279:DNA, Viral; D014764:Viral Proteins; D004259:DNA-Directed DNA Polymerase; D000251:Adenosine Triphosphatases; D004265:DNA Helicases