Reporter of I-element transposition. Contains an I-element (flanked by P-element ends) with an EGFP cassette inserted in the antisense direction in the non-coding sequence of the I-element. The EGFP sequence contains a disruptive intron that can be spliced during transcription of the retrotransposon, but not during transcription of EGFP. Thus, EGFP protein is only expressed after mobilization of the I-element in the reporter transgene, which generates a new copy of an I-element containing EGFP without the disrupting intron.