Related Experiment Video
Updated: Aug 12, 2026

Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites
Published on: March 22, 2016
A nucleoprotein complex mediates the integration of retroviral DNA
B Bowerman1, P O Brown, J M Bishop
1Department of Biochemistry and Biophysics; University of California, San Francisco 94143.
Abstract:
The integration of viral DNA into the host genome is an essential step in the retrovirus life cycle. To understand this process better, we have examined the native state of viral DNA in cells acutely infected by murine leukemia virus (MLV), using both a physical assay for viral DNA and a functional assay for integration activity (Brown et al. 1987). The viral DNA and integration activity copurify during velocity sedimentation, gel filtration, and density equilibrium centrifugation, indicating that viral DNA is in a large (approximately 160S) nucleoprotein complex that includes all functions required for integration activity in vitro. Analysis by immunoprecipitation shows that the viral capsid protein is part of the active nucleoprotein complex, but recognition of the complex by only a subset of anti-capsid sera implies that the protein is constrained conformationally. The viral DNA within this structure is accessible to nucleases; the effects of nucleases on the integrity of the complex suggest that the integration-competent particle is derived from and similar to the core of extracellular virions.
Related Concept Videos
Retrovirus Life Cycles
Retroviruses
LTR Retrotransposons
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
Mechanisms of Retrovirus-induced Cancers
Mechanisms of Retrovirus-induced Cancers
Size and Structure of Viral Genomes

