Related Experiment Videos
Integration of IS3 into IS2 generates a short sequence duplication.
Molecular & General Genetics : MGG
|January 1, 1979
Summary
The IS3 mobile genetic element can integrate into the IS2-43 allele, causing a Gal- phenotype. Precise excision of IS3 occurred at a low frequency, forming novel flanking duplications.
Area of Science:
- Genetics
- Molecular Biology
- Microbiology
Background:
- The Gal+ allele IS2-43 is known to segregate Gal- clones.
- Mobile genetic elements play a significant role in genome evolution and gene regulation.
Purpose of the Study:
- To investigate the mechanism behind the segregation of Gal- clones from the Gal+ allele IS2-43.
- To characterize the integration and excision of the IS3 element and its impact on the IS2-43 allele.
- To analyze the DNA sequence features of the IS3 element and its flanking regions.
Main Methods:
- Analysis of Gal- segregants from the Gal+ IS2-43 allele.
- DNA sequencing to identify integrated elements and flanking sequences.
- Quantification of precise excision events.
Main Results:
- One out of 11 Gal- segregants resulted from the integration of the IS3 element into IS2-43.
- Precise excision of the integrated IS3 element was observed at a low frequency (5 x 10^-9/cell/generation).
- DNA sequence analysis revealed that the IS3 element termini are imperfect inverted repeats and it is flanked by a novel 3bp or 4bp duplication.
Conclusions:
- The integration of IS3 into IS2-43 is a mechanism generating Gal- clones.
- The IS3 element exhibits precise excision, albeit at a low rate.
- The flanking duplications generated by IS3 integration are of a size not previously observed for other mobile elements, suggesting unique integration or excision mechanisms.