Structural insights into distinct mechanisms of RNA polymerase II and III recruitment to snRNA promoters

Syed Zawar Shah, Thomas N. Perry, Andrea Graziadei, Valentina Cecatiello, Thangavelu Kaliyappan, Agata D. Misiaszek, Christoph W. Müller, Ewan P. Ramsay () and Alessandro Vannini ()
Additional contact information
Syed Zawar Shah: Human Technopole
Thomas N. Perry: Human Technopole
Andrea Graziadei: Human Technopole
Valentina Cecatiello: Human Technopole
Thangavelu Kaliyappan: Institute of Cancer Research
Agata D. Misiaszek: European Molecular Biology Laboratory (EMBL)
Christoph W. Müller: European Molecular Biology Laboratory (EMBL)
Ewan P. Ramsay: Human Technopole
Alessandro Vannini: Human Technopole

Nature Communications, 2025, vol. 16, issue 1, 1-19

Abstract: Abstract RNA polymerase III (Pol III) transcribes short, essential RNAs, including the U6 small nuclear RNA (snRNA). At U6 snRNA genes, Pol III is recruited by the snRNA Activating Protein Complex (SNAPc) and a Brf2-containing TFIIIB complex, forming a pre-initiation complex (PIC). Uniquely, SNAPc also recruits Pol II at the remaining splicesosomal snRNA genes (U1, 2, 4 and 5). The mechanism of SNAPc cross-polymerase engagement and the role of the SNAPC2 and SNAPC5 subunits remain poorly defined. Here, we present cryo-EM structures of the full-length SNAPc-containing Pol III PIC assembled on the U6 snRNA promoter in the open and melting states at 3.2–4.2 Å resolution. The structural comparison revealed differences with the Saccharomyces cerevisiae Pol III PIC and the basis of selective SNAPc engagement within Pol III and Pol II PICs. Additionally, crosslinking mass spectrometry localizes SNAPC2 and SNAPC5 near the promoter DNA, expanding upon existing descriptions of snRNA Pol III PIC structure.

Date: 2025
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/s41467-024-55553-8 Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:16:y:2025:i:1:d:10.1038_s41467-024-55553-8

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-024-55553-8

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().