In the third instar larva, ScerGAL4for.pr3 is expressed in perineurial surface glial cells in the central and peripheral nervous systems; in circular and longitudinal midgut muscles; in the fat body; in primary cells of the anterior Malpighian tubule; extensively in the body wall muscles; in the larval salivary gland; and in a number of midggt cell types, including copper cells, a subset of enteroendocrine cells of the anterior midgut, and midgut large flat cells. Expression is not observed in neurons.