DOT1L-mediated repression of non-canonical PRC1 target genes maintains the pro-proliferative identity of Diffuse Large B Cell Lymphoma

ABSTRACT: To determine whether the inhibition of DOT1L (EPZ-5675) affects the enrichment of components within specific non-canonical PRC1 (ncPRC1) complexes, we performed rapid immunoprecipitation mass spectrometry of endogenous protein (RIME) of BCOR (ncPRC1.1) and PCGF6 (ncPRC1.6) for human GCB-DLBCL cell lines Oci-Ly7 and SUDHL4 cell lines. For each replicate, 100x10^6 cells were treated with DMSO (< 0.01% [v/v]) or EPZ-5675 (DOT1Li) before fixing with 1% formaldehyde (Electron Microscopy Sciences) for 10 minutes. Samples were processed as previously described (PMID: 26797456). Briefly, nuclei were isolated and chromatin was sheared using a pico-Biorupter (Diagenode) 30 seconds on/off until obtaining DNA fragment sizes between 250-500 bp. 9 µg of anti-BCOR (Bethyl Laboratories, cat. No. A301-673A), anti-PCGF6 (Proteintech, cat. No. 24103-1-AP), and rabbit IgG (Millipore, cat. No. 12-370) antibodies were coupled to 50 µL protein A dynabeads (Invitrogen, cat. No. 10008D) for immunoprecipitation. After overnight immunoprecipitation, beads were washed using RIPA and 100mM ammonium bicarbonate. Dry-bead pellets were stored at -80°C until on-bead trypsin digestion was performed and protein content was quantified.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Line Cell

DISEASE(S): Diffuse Large B-cell Lymphoma

SUBMITTER: Onno Bleijerveld  

LAB HEAD: Onno Bleijerveld

PROVIDER: PXD061504 | Pride | 2026-10-19

REPOSITORIES: Pride