PXD074618-1

PXD074618 is an original dataset announced via ProteomeXchange.

Title	Cryo-EM structure, enzymatic activity and genome targeting of canonical PRC1
Description	Canonical Polycomb Repressive Complex 1 (cPRC1) preserves cell fate decisions by repressing inappropriate transcription of developmental regulator genes. We report the cryo–electron microscopy structure of tetrameric human cPRC1 bound to a nucleosome, in complex with native ubiquitin-conjugating enzyme UBCH5C. cPRC1 adopts a compact architecture, orchestrated by the PHC2HD domain which is sandwiched between BMI1 and a structural lobe formed by the CBX7C-box and RING1BRAWUL domains. In this compact conformation, RING1B, BMI1 and PHC2 form an extended interface that stably positions UBCH5C on the nucleosome to enable efficient monoubiquitination of histone H2A at lysine 119 (H2Aub1). This tightly organized architecture is conserved in Drosophila cPRC1, where mutational analyses establish the Polyhomeotic (Ph) subunit as the key scaffolding and targeting factor. While the PhHD domain is critical for complex assembly, the PhSAM domain is dispensable for assembly but essential for recruiting cPRC1 to target genes, a prerequisite for cPRC1-mediated H2A monoubiquitination
HostingRepository	PRIDE
AnnounceDate	2026-08-14
AnnouncementXML	Submission_2026-08-14_04:49:24.382.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Barbara Steigenberger
SpeciesList	scientific name: Drosophila melanogaster (Fruit fly); NCBI TaxID: NEWT:7227;
ModificationList	No PTMs are included in the dataset
Instrument	Orbitrap Eclipse; timsTOF HT

Revision	Datetime	Status	ChangeLog Entry
0	2026-02-18 22:13:38	ID requested
⏵ 1	2026-08-14 04:49:24	announced

Dataset with its publication pending

submitter keyword: Polycomb Repressive Complex 1/ PRC1/ histone H2A monoubiquitination/gene regulation/transcription repression/targeting/PREs

Jürg Müller
contact affiliation	Max-Planck Institute of Biochemistry, Laboratory of Chromatin Biology, Am Klopferspitz 18, 82152 Martinsried, Germany
contact email	muellerj@biochem.mpg.de
lab head
Barbara Steigenberger
contact affiliation	MPI of Biochemistry
contact email	steigenberger@biochem.mpg.de
dataset submitter

Dataset FTP location NOTE: Most web browsers have now discontinued native support for FTP access within the browser window. But you can usually install another FTP app (we recommend FileZilla) and configure your browser to launch the external application when you click on this FTP link. Or otherwise, launch an app that supports FTP (like FileZilla) and use this address: ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2026/08/PXD074618

PRIDE project URI

• PRIDE
  1. PXD074618
     1. Label: PRIDE project
     2. Name: Cryo-EM structure, enzymatic activity and genome targeting of canonical PRC1