English: 3D Structure of the CRISPR-Cas9 Interference Complex. 3D models are based on crystallization data using PDB sequence 4OO8. 1A: Structure of Cas9 protein. REC lobe (recognition) and NUC lobe (nuclease) are indicated as well as functional domains PI (PAM interacting), HNH, and RuvC. 1B: Abstract depiction of Cas9. 2A: Conformation of crRNA, tracrRNA, and DNA. 2B: Abstract depiction of molecules is shown in 2A. 3A: 3D structure of the complete interference complex. The NUC lobe is shown semi-transparent for clarity. 3B: Abstract depiction of the interference complex.