Construct: Amino acid replacement: T?Q. Amino acid replacement: Q?T. Amino acid replacement: T?S.
Expression of Tcas\ftzNTS.Scer\UAS, under the control of Scer\GAL4arm.PS, causes the homeotic transformation of segments T2 and T3 into T1, as shown by the appearance of ectopic T1 beard bristles on these segments. Scer\GAL4arm.PS>Tcas\ftzNTS.Scer\UAS expression also causes head involution to fail.