Genomic sequence has been re-integrated into the attP site in TI{TI}stanΔ.attP, reconstituting a stan locus in which sequence encoding amino acids 3087 to the end of the open reading frame has been replaced with SGGGGSGSSYSLESIGTSSGGGGS (this encodes an FRT site flanked by a linker on each side). In addition, the stan coding sequence is tagged with EGFP downstream of codon 355.