A Pan-Cancer Catalogue of Cancer Driver Protein Interaction Interfaces
a) The PDB coordinate set 3HMM contains 2 chains, A (a region of PIK3CA, shown in gray) and B (a region of PIK3R1, shown in brown). Residues from PIK3R1 colored in red make the interaction interface with PIK3CA. b) Using BLAST we then map these residues to the corresponding ENSEMBL protein, define a PPI interface (shown in red). Note that the interface is not continuous in sequence. c) Distribution of mutations in PIK3R1 across all cancer types. d) Using e-Driver we can identify the interface between PIK3R1 and PIK3CA as strongly enriched in missense somatic mutations (p < 2e-6).