We have isolated and characterized two new protein kinase C (PKC) genes from D. melanogaster. One, dPKC98F, maps to chromosome region 98F and displays over 60% amino acid sequence identity with members of a recently described "PKC-related" subfamily in mammals. The other, dPKC53E(ey), maps to region 53E4-7 on the second chromosome and lies within 50 kb of PKC gene previously characterized (dPKC). While dPKC98F transcripts are expressed throughout development, expression of the two genes mapping at cytogenetic location 53E is primarily in adults. dPKC98F and the previously reported 53E gene are transcribed predominantly in brain tissue. In contrast, dPKC53E(ey) is transcribed only in photoreceptor cells. We will discuss the significance of this tissue-specific localization with regard to phototransduction.