|  | Class c: Alpha and beta proteins (a/b) [51349] (148 folds) | 
|  | Fold c.55: Ribonuclease H-like motif [53066] (7 superfamilies) 3 layers: a/b/a; mixed beta-sheet of 5 strands, order 32145; strand 2 is antiparallel to the rest | 
|  | Superfamily c.55.1: Actin-like ATPase domain [53067] (16 families)  duplication contains two domains of this fold | 
|  | Family c.55.1.1: Actin/HSP70 [53068] (8 proteins) | 
|  | Protein Actin [53073] (7 species) | 
|  | Species Nematode (Caenorhabditis elegans) [TaxId:6239] [64086] (1 PDB entry) | 
|  | Domain d1d4xa1: 1d4x A:4-146 [59107] Other proteins in same PDB: d1d4xg_ complexed with atp, ca, mg, so2, so4 | 
|  | Domain d1d4xa2: 1d4x A:147-375 [59108] Other proteins in same PDB: d1d4xg_ complexed with atp, ca, mg, so2, so4 | 
Timeline for Species Nematode (Caenorhabditis elegans) [TaxId:6239] from c.55.1.1 Actin: