Determination of local chromatin composition by CasID

作者:Schmidtmann Elisabeth; Anton Tobias; Rombaut Pascaline; Herzog Franz; Leonhardt Heinrich*
来源:Nucleus, 2016, 7(5): 476-484.
DOI:10.1080/19491034.2016.1239000

摘要

Chromatin structure and function are determined by a plethora of proteins whose genome-wide distribution is typically assessed by immunoprecipitation (ChIP). Here, we developed a novel tool to investigate the local chromatin environment at specific DNA sequences. We combined the programmable DNA binding of dCas9 with the promiscuous biotin ligase BirA* (CasID) to biotinylate proteins in the direct vicinity of specific loci. Subsequent streptavidin-mediated precipitation and mass spectrometry identified both known and previously unknown chromatin factors associated with repetitive telomeric, major satellite and minor satellite DNA. With super-resolution microscopy, we confirmed the localization of the putative transcription factor ZNF512 at chromocenters. The versatility of CasID facilitates the systematic elucidation of functional protein complexes and locus-specific chromatin composition.

  • 出版日期2016