We previously identified a murine primary response gene family containing three members; TIS11, TIS11B and TIS11D. Using degenerate oligonucleotides derived from conserved regions of the mouse TIS11 family cDNAs as primers and Drosophila genomic DNA as template for polymerase chain reaction amplification, we have identified a fly TIS11 homologue called DTIS11. The DTIS11 protein shares 90% sequence identity with the murine TIS11B and TIS11D proteins, over a 74 amino acid region that contains two CX8CX5CX3H repeated motifs separated by 18 amino acids. DTIS11 maps to region 11B(14-16) on the X-chromosome. Northern blot and in situ hybridization show that a maternal 3 kb message is present in embryos of early developmental stages. A 6 kb DTIS11 mRNA subsequently appears. In KC embryonal cells, both a strong 3 kb message and a less intense 6 kb message are present. The larger (6 kb) message is modestly induced in KC cells by both forskolin and tetradecanoyl phorbol acetate, and is stabilized by cycloheximide.