Sticky digestive liquid from a carnivorous plant Drosera adelae contains a novel S-like ribonuclease (RNase). In normal plants, S-like RNases corresponding to the D. adelae RNase, which we named DA-I, are induced by phosphate starvation and/or wounding. In this study, the genomic organization of the DA-I gene (da-I) and its 5'-and 3'-flanking sequences were analyzed. The da-I was found to be a gene of single copy in D. adelae. The gene comprises four exons and three introns, with a similarity to the structure of the Class C S-like RNase genes. A nucleotide sequence analysis of the 5'-flanking region revealed that a canonical TATA box sequence (TATAAAT) lies between positions -33 to -27 and a CCAAT box is located between positions -84 to -80 relative to the transcription start site (+1). Although the gene is constitutively transcribed in glandular cells, three wound responsive and two phosphate starvation responsive DNA elements were found within the region between -160 to +2, presenting a riddle regarding the mechanism for the transcriptional regulation of the da-I.