Superclass numberSuperclass nameQuantity of classesQuantity of familiesExamples of TFs
0Yet undefined DNA-binding domains (Superclass ‘0’)510PSPC1, RFXANK, NRF1
1Basic Domains318c-Jun, c-Fos, Nrf2
2Zinc-coordinating DNA-binding domains825ER, GATA-1, RXR-α
3Helix–turn–helix722HOXA9, Oct-3/4, E2F-1
4Other all-α-helical DNA-binding domains28SOX2, TCF-7, UBF
5α-Helices exposed by β-structures27MEF2, SRF, AIRE
6Immunoglobulin fold716RelA, STAT1, p53
7β-Hairpin exposed by an α/β-scaffold23SMAD4, GCM1, NF-1A
8β-Sheet binding to DNA22TBP, TBPL1, HMGA1
9β-Barrel DNA-binding domains11DbpA, YB-1, YBX2