UAS sequences regulate expression of a mutated form of 'λ-Egfr' (a Y1095F amino acid replacement has been introduced into the Egfr intracellular domain). FlyBase curator comment: '.lgr;-Egfr' consists of the dimerization domain of the bacteriophage .lgr; cI repressor (included to induce constitutive dimerization of the encoded protein), transmembrane sequence (from btl) and the intracellular domain of Egfr.