lexAop regulatory sequences and a minimal Hsp70 promoter (derived from the pUASTLOTattB vector) are fused upstream of a fusion protein that encodes an antibody-based Tag:HA trap that localizes to the extracellular matrix of the basal lamina. The fusion protein comprises the vkg coding sequence, with a sequence cassette that encodes mCherry and the scFv(antiHA-X15F11) single-chain antibody inserted between the first and second exon. (Generated by P1cre-mediated excision of the UAS regulatory sequences present in P{lexAop-UAS-GrabHA.ECM.mCh}).