The distribution of hth protein and transcripts in wild type imaginal discs is the same as that of lacZ in the enhancer trap line. Enhancer trap expression is observed in the wing disc in the notum, winge hinge, and ventral pleura. In the leg discs, expression is in the periphery region corresponding to the proximal segments of the legs. In the antennal disc, the expression is in all but the arista region. In the eye disc, hth expression is strong in the anterior region surrounding the eye field, including the regions corresponding to the ptilinum, ocellus, and head capsules, and weak in the posterior and lateral margins of the disc. hth is also expressed in all cells of the peripodial membrane in the eye disc. Weak expression is observed in the posterior region composed of mature photoreceptors. This expression pattern generally coincides with that of exd.

hth enhancer trap expression is an excellent reporter of hth gene expression.