Fig. 1: IBG1 degrades BRD2 and BRD4 independently of DCAF15.
From: Targeted protein degradation via intramolecular bivalent glues
a, Structure of IBG1. b, BET protein degradation activity of IBG1. HEK293 cells were treated for 6 h with DMSO, E7820 (1 μM) or increasing concentrations of IBG1. BET protein was quantified by immunoblot. Data representative of n = 3 independent experiments. c, Whole-proteome changes after degrader treatment. Quantitative proteomics in KBM7 cells was performed after 6 h of treatment with DMSO, IBG1 (1 nM) or dBET6 (10 nM). log2-transformed fold change and −log10-transformed Benjamini–Hochberg adjusted one-way analysis of variance (ANOVA) P value compared with DMSO treatment. n = 3 biological replicates. d, NanoBRET kinetic degradation assay. BromoTag–HiBiT–BRD4 knock-in HEK293 cells were treated with IBG1 with or without MLN4924 (10 µM) pre-treatment for 1 h. Mean of n = 3 biological replicates. RLU, relative light units. e, NanoBRET kinetic ubiquitination assay. LgBiT-transfected HiBiT–BromoTag–BRD4 knock-in HEK293 cells were treated with IBG1 at indicated concentrations or at 10 nM following pre-treatment with JQ1, E7820 (both 10 µM) or MLN4924 (1 µM) for 1 h. Mean of n = 4 biological replicates. f, DCAF15-independent BET protein degradation. Wild-type (WT) and DCAF15-knockout (KO) HCT-116 cells were treated with increasing concentrations of IBG1 for 6 h and BET protein was quantified by immunoblot. Data representative of n = 3 independent experiments.
