ACBI1

ACBI1 is a highly potent, cooperative proteolysis-targeting chimera (PROTAC) that induces selective degradation of the BAF (SWI/SNF) chromatin remodeling complex subunits SMARCA2 (BRM), SMARCA4 (BRG1), and PBRM1 by recruiting them to the von Hippel–Lindau (VHL) E3 ubiquitin ligase.[1][3][8] Developed as a chemical probe by Boehringer Ingelheim and distributed via the opnMe platform, ACBI1 links a ligand for SMARCA2/4–PBRM1 to a VHL-binding moiety, promoting ubiquitination and proteasomal degradation of these ATP-dependent chromatin remodelers, with reported DC50 values in the low nanomolar range (approximately 6 nM for SMARCA2, 11 nM for SMARCA4, and 32 nM for PBRM1 in cellular assays).[1][2][6] By depleting these key epigenetic regulators, ACBI1 serves as a research tool to study BAF complex biology and synthetic lethal vulnerabilities in cancer and other diseases where SWI/SNF function is aberrant, but it is not a clinically developed pharmaceutical agent.[1][4][7]