Related Experiment Videos
Adenoviruses with nonidentical terminal sequences are viable
1Department of Biology, McMaster University, Hamilton, Ontario, Canada.
Journal of Virology
|December 1, 1989
Summary
Adenoviruses with nonidentical terminal sequences are viable, rapidly converting to identical ends. This suggests efficient repair mechanisms utilizing template sequences during replication.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- Adenovirus genomes feature linear DNA with inverted terminal repeat sequences (ITRs).
- The necessity of identical ITRs for adenovirus viability has been a key question in viral genetics.
Purpose of the Study:
- To investigate the importance of identical terminal sequences for adenovirus viability.
- To analyze the behavior of hybrid adenoviruses with distinct ITRs.
Main Methods:
- Utilized wild-type adenovirus type 5 (Ad5) and a variant Ad2 strain.
- Created and analyzed a hybrid virus (sub54) through recombination.
- Employed Southern blotting and plaque purification techniques.
- Cloned the hybrid adenovirus genome as a bacterial plasmid (pFG154) for transfection studies.
Main Results:
- Hybrid viruses (sub54) with nonidentical Ad2 and Ad5 ITRs were viable but rapidly converted to viruses with identical ends.
- Transfection with a plasmid containing mixed ITRs yielded progeny with various terminal combinations, confirming viability of nonidentical termini.
- Pure populations of viruses with nonidentical termini could not be isolated, indicating rapid repair.
Conclusions:
- Adenoviruses can tolerate nonidentical terminal sequences, though they are unstable in vivo.
- Efficient repair mechanisms likely convert nonidentical termini to identical ones, possibly using strand displacement replication and panhandle formation.