Schematic diagram of the UL15 gene. (A) Northern blot hybridization. Total RNA was isolated from DEV-infected CEF cells at 48 h p. i. RNA samples were then separated, blotted and hybridized with the probes and analyzed. The size of the mRNA was calculated according to the RNA size standard shown at the left. (B) The cDNA ends of UL15 and UL15.5. The promoters were predicted on the Berkeley Drosophila Genome Project's neural network promoter search engine (http://www.fruitfly.org/seq_tools/promoter.html). The TATA box and poly (A) signal elements were predicted on the TRANSFAC motif library (http://motif.genome.jp/) and the POLYADQ polyadenylation (polyA) signal search engine (http://rulai.cshl.org/tools/polyadq/polyadq_form.html), respectively. The predicted promoter sequences of UL15 and UL15.5 are shown, the TATA box, polyA signal motifs and polyA sequences are underlined, and the TSSs indicated by 5'-RACE are shown in red. The putative start and stop codons are in bold. (C) The DEV UL15 gene consists of two exons, exon I (Ex I) and exon II (Ex II), which are indicated by red arrows. The putative UL16 (green) and UL17 (blue) are located in the opposite orientation within the intron of UL15. The UL15 transcription start sites (TSS) and poly (A) sequences are indicated by black arrows. The UL15.5 TSS is indicated by the dashed arrow within Ex I of UL15. The ruler above the locus shows the relative position of the genes in kb (K).