The attP-flanked recombination-mediated cassette exchange (RMCE) cassette in the TI{TI}atow.RMCE insertion has been replaced with sequence that adds back ato 5' and 3' regulatory sequence that was missing in TI{TI}atow.RMCE, and also inserts the coding sequence for sc in place of the deleted ato ORF, such that sc is expected to be expressed under the control of the endogenous ato regulatory sequences.