DT-A corresponds to the catalytic A subunit encoded by the Corynephage beta Diphtheria toxin (DT) gene (UniProtKB:P00588). DT-A can be used as a cell ablation tool; it inhibits protein synthesis via ADP-ribosylation of elongation factor 2 (reviewed in PMID:164179). By expressing the DT-A subunit without the B subunit that is also normally encoded by the Corynephage beta DT gene, the cell ablation is rendered cell autonomous (FBrf0055894).