@article{d92d1dc2b2a54ecb8d84658173c3a807,
title = "The architecture of the spliceosomal U4/U6.U5 tri-snRNP",
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 {\AA} 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.",
author = "Nguyen, {Thi Hoang Duong} and Galej, {Wojciech P.} and Bai, {Xiao Chen} and Savva, {Christos G.} and Newman, {Andrew J.} and Scheres, {Sjors H W} and Kiyoshi Nagai",
note = "Funding Information: Acknowledgements We thank S. Chen, G. McMullan, J. Grimmett and T. Darling for smooth running of the EM and computing facilities; P. da Fonseca, N. Unwin, I. Sanchez Fernandez, A. Amunts, P. Emsley, G. Murshudov and A. Brown for advice; A. Easter and L. Passmore for reagents; M. Skehel for mass spectrometry; and J. Li, Y. Kondo and the members of the spliceosome group for help and advice throughout the project. We are grateful to R. Henderson, D. Barford, S. Fica, P.-C. Lin and L. Strittmatter for critical reading of the manuscript. We thank V. Ramakrishnan, J. L{\"o}we and R. Henderson for their continuing support and encouragements. T.H.D.N. was supported in part by a Herchel Smith Research Studentship. X.-c.B. was supported by a European Union Marie Curie Fellowship. The project was supported by the Medical Research Council (MC_U105184330 to K.N. and MC_UP_A025_1013 to S.H.W.S.). Publisher Copyright: {\textcopyright} 2015 Macmillan Publishers Limited. All rights reserved.",
year = "2015",
month = jul,
day = "1",
doi = "10.1038/nature14548",
language = "English (US)",
volume = "523",
pages = "47--52",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "7558",
}