Lineage for Family a.4.12.1: Trp repressor, TrpR

1. Root: SCOPe 2.02

2. Class a: All alpha proteins [46456] (284 folds)

3. Fold a.4: DNA/RNA-binding 3-helical bundle [46688] (14 superfamilies) core: 3-helices; bundle, closed or partly opened, right-handed twist; up-and down

4. Superfamily a.4.12: TrpR-like [48295] (3 families) contains an extra shared helix after the HTH motif

5. Family a.4.12.1: Trp repressor, TrpR [48296] (1 protein) intertwined dimer of identical 6-helical subunits