To find cellular protein binding partners of the NLRP1 inflammasome, FLAG-tagged full length NLRP1 (or a GFP-FLAG protein control) was ectopically expressed in HEK 293T cells and affinity purified from cell lysates (Note: the NLRP1-FLAG-containing lysate samples were affinity purified in the presence or absence of excess proline) before proteins were reduced, alkylated, and trypsinized before TMT labelling and pooling of the differentially tested lysates to give three conditions (1. NLRP1-FLAG; 2. GFP-FLAG; 3. NLRP1-FLAG+proline) in duplicate. These data represent the results following sample and data processing.