C-BERST: Defining subnuclear proteomic landscapes at genomic elements with dCas9-APEX2

Mapping proteomic composition at distinct genomic loci and subnuclear landmarks in living cells has been a long-standing challenge. Here we report that dCas9-APEX2 Biotinylation at genomic Elements by Restricted Spatial Tagging (C-BERST) allows the unbiased mapping of proteomes near defined genomic loci, as demonstrated for telomeres and centromeres. C-BERST enables the high-throughput identification of proteins associated with specific sequences, facilitating annotation of these factors and their roles in nuclear and chromosome biology.