The 2micron plasmid in Yeast Sacharomyces cerevisiae
- each yeast cell contain about 100 copies of the 2micron plasmid
- 2micron plasmid replicate autonomously
- exist in 2 isomers inside each cell, each about 50% .
- FLP invert a sequence between 2
- FLP mediated recombination plays an important role in plasmid amplification
- Excessive amplification is toxic for the cell, so FLP is tighly controlled
- 3 repeat of 13 bp (a, b, c)
- 8bp (AT)-rich core region, with assymetric sequence, dictate directionnality.
- assymetric distribution and orientation of abc sites arround the core sequence:
-----c-----→ -----b-----→ ≤core≥ ←------a-------