The human cell surface transmembrane protein CD36 has important roles in cell adhesion and signal transduction. There is a related rat protein, LIMP II (also known as rLGP85), which is a well-characterized lysosomal membrane protein. The two proteins define a distinct family of receptor molecules with two membrane-spanning domains. We have identified a new member of this family, encoded by a Drosophila gene called emp (epithelial membrane protein). The emp protein, as predicted from the nucleotide sequence, is 519 amino acid residues long. It shows striking similarity throughout most of its sequence to both CD36 and LIMP II. Drosophila emp transcripts are expressed during embryogenesis in various epithelial cell types derived from the ectoderm. During larval development, we detect emp transcripts in the epithelial cells of wing imaginal discs, in the precursor cells for adult epidermal structures. These expression patterns suggest a role of emp protein in the development or cellular function of epithelial cells.