FLP

The 2micron plasmid in Yeast Sacharomyces cerevisiae

General

• 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

• 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

FRT site

• 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-------