The architecture of the spliceosomal U4/U6.U5 tri-snRNP

Thi Hoang Duong Nguyen, Wojciech P. Galej, Xiao Chen Bai, Christos G. Savva, Andrew J. Newman, Sjors H W Scheres, Kiyoshi Nagai

Research output: Contribution to journalArticle

128 Scopus citations

Abstract

U4/U6.U5 tri-snRNP is a 1.5-megadalton pre-assembled spliceosomal complex comprising U5 small nuclear RNA (snRNA), extensively base-paired U4/U6 snRNAs and more than 30 proteins, including the key components Prp8, Brr2 and Snu114. The tri-snRNP combines with a precursor messenger RNA substrate bound to U1 and U2 small nuclear ribonucleoprotein particles (snRNPs), and transforms into a catalytically active spliceosome after extensive compositional and conformational changes triggered by unwinding of the U4 and U6 (U4/U6) snRNAs. Here we use cryo-electron microscopy single-particle reconstruction of Saccharomyces cerevisiae tri-snRNP at 5.9 Å resolution to reveal the essentially complete organization of its RNA and protein components. The single-stranded region of U4 snRNA between its 3′ stem-loop and the U4/U6 snRNA stem I is loaded into the Brr2 helicase active site ready for unwinding. Snu114 and the amino-terminal domain of Prp8 position U5 snRNA to insert its loop I, which aligns the exons for splicing, into the Prp8 active site cavity. The structure provides crucial insights into the activation process and the active site of the spliceosome.

Original languageEnglish (US)
Pages (from-to)47-52
Number of pages6
JournalNature
Volume523
Issue number7558
DOIs
StatePublished - Jul 1 2015

ASJC Scopus subject areas

  • Medicine(all)
  • General

Fingerprint Dive into the research topics of 'The architecture of the spliceosomal U4/U6.U5 tri-snRNP'. Together they form a unique fingerprint.

  • Cite this

    Nguyen, T. H. D., Galej, W. P., Bai, X. C., Savva, C. G., Newman, A. J., Scheres, S. H. W., & Nagai, K. (2015). The architecture of the spliceosomal U4/U6.U5 tri-snRNP. Nature, 523(7558), 47-52. https://doi.org/10.1038/nature14548