Related Experiment Video
Updated: Aug 20, 2026

Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites
Published on: March 22, 2016
Differential induction of structural changes in the simian virus 40 origin of replication by T antigen
J A Borowiec1, F B Dean, J Hurwitz
1Program in Molecular Biology and Virology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
Abstract:
The ATP-dependent binding of the simian virus 40 (SV40) large tumor antigen (T antigen) to the SV40 origin of replication (ori) results in the structural distortion of two critical elements within flanking regions of ori and the untwisting of the DNA helix. We examined the effect of changes in temperature, ATP concentration, and other reaction parameters on the generation of these DNA structural changes. We found that induction of the two localized structural transitions were highly and differentially sensitive to reaction conditions. Significant distortion of the early palindrome element, shown previously to result from DNA melting, required low levels of ATP (10 to 30 microM) but temperatures above 25 degrees C. Distortion of the AT tract occurred at low temperatures (5 degrees C) but required relatively high concentrations of ATP (greater than 300 microM). Thus, T antigen can induce structural changes within one critical element of ori without generating significant structural distortion within the second element. The response of ori untwisting to reaction conditions generally increased in parallel with or fell intermediate between the inductions of localized structural transitions. We suggest that ori untwisting and localized structural distortions are interdependent consequences of T-antigen binding to ori. These results suggest a model for the structural events occurring during the initial steps of SV40 DNA replication.
More Related Videos
13:13Single-cell Quantitation of mRNA and Surface Protein Expression in Simian Immunodeficiency Virus-infected CD4+ T Cells Isolated from Rhesus macaques
Published on: September 25, 2018
05:22Electrophoretic Analysis of Replication Through Structure-Prone DNA Repeats Within the SV40-Based Human Episome
Published on: September 13, 2024
Related Concept Videos
Retrovirus Life Cycles
Viral Mutations
Mechanisms of Retrovirus-induced Cancers
Size and Structure of Viral Genomes