Fig. 4.

ncPRC1.6 can be formed in the absence of MAX. (A) Schematic representation of the main components of ncPRC1.6. (B, Left) Density plots, from the immunoprecipitation–mass spectrometry (IP-MS) results, showing the proteins that form stable complexes with MGA in the Lu134 and Lu165 cells without MAX (Mock) or in cells that express ectopic and endogenous-like levels of MAX ((lo)MAX) (see also Dataset S3 for detailed information). The proteins from ncPRC1.6 are indicated. The IP-MS results were analyzed based on the enrichments of peptides precipitated by anti-MGA antibodies relative to IgG controls (transforming 0 to .1) for each indicated cell line and condition. (C) Confirmation of the MGA-containing complexes in each cell line and condition. MGA was immunoprecipitated from whole extracts followed by immunoblot of the indicated proteins. HDAC4 was included as a negative control.