Expression of Tcas\ftzScer\UAS.T:Hsap\MYC, under the control of Scer\GAL4arm.PS, causes transformation of the T1 segment into T2, as evidenced by a reduction of the T1 beard, and head involution defects. Expression of Tcas\ftzScer\UAS.T:Hsap\MYC, under the control of Scer\GAL4Dll-md23, causes the complete transformation of the arista and antennal 3 segment into tarsal segments 1-5 and claw.