In our attempts to use this transgene as a reporter of Flip activity in the ovary we have found significant expression of GFP in the female germline and follicle cells prior to exposure to Flipase.
This construct contains a "Flipout STOP" cassette with approx. 2kb of sequence immediately downstream of the Hsp70Ab gene intended to prevent expression from the ubiquitin promoter. We note however that this cassette extends into the next two adjacent genes CG3281 and aur and would place the aur promoter immediately adjacent and in the same orientation to the GFP reporter. These sequences may be responsible for this expression.
We have not searched further for expression in other tissues.
Note: This same fragment is present in other constructs carrying FBal0052292 (Hsp70AbpolyA).