In this study, the complementary DNA (cDNA) of Japanese pufferfish Takifugu rubripes tumour necrosis factor‐related apoptosis‐inducing ligand (TRAIL) was cloned by reverse‐transcription PCR. The open reading frame of the TRAIL consisted of 870 bases. The
deduced amino‐acid sequence of the TRAIL showed a high homology with the sequences of other teleosts. Recombinant soluble TRAIL was fused with a small ubiquitin‐related modifier gene to enhance the soluble expression level in Escherichia coli BL21 (DE3). In vitro,
the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrasodium bromide (MTT) assay indicated that the purified soluble TRAIL was able to induce apoptosis of Jurkat and HeLa cells in a dose‐dependent manner.