Figure 11.

PPIG structures in and out of the spliceosomal context. In (A), the isomerase domain of PPIG is shown in cartoon representation (overlay of PDB IDs: 2GW2, 2WFI, and 2WFJ). Selected residues in the catalytic site, along with regions of protein–protein interactions, are labeled. In (B), the neighborhood around the isomerase domain of PPIG in the catalytic C spliceosome (PDB ID: 5YZG). Potential interactions between PPIG and SNW1, CWC15, and PRPF8 are highlighted. No model exists for the roughly 600 residues outside of the PPIG isomerase domain.