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Structure of the human 20S U5 snRNP.

ABSTRACT: The 20S U5 small nuclear ribonucleoprotein particle (snRNP) is a 17-subunit RNA-protein complex and a precursor of the U4/U6.U5 tri-snRNP, the major building block of the precatalytic spliceosome. CD2BP2 is a hallmark protein of the 20S U5 snRNP, absent from the mature tri-snRNP. Here we report a high-resolution cryogenic electron microscopy structure of the 20S U5 snRNP, shedding light on the mutually exclusive interfaces utilized during tri-snRNP assembly and the role of the CD2BP2 in facilitating this process.

SUBMITTER: Schneider S

PROVIDER: S-EPMC11102862 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature

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Structure of the human 20S U5 snRNP.

Schneider Sarah S Brandina Irina I Peter Daniel D Lagad Sonal S Fraudeau Angelique A Portell-Montserrat Júlia J Tholen Jonas J Zhao Jiangfeng J Galej Wojciech P WP

Nature structural & molecular biology 20240311 5

The 20S U5 small nuclear ribonucleoprotein particle (snRNP) is a 17-subunit RNA-protein complex and a precursor of the U4/U6.U5 tri-snRNP, the major building block of the precatalytic spliceosome. CD2BP2 is a hallmark protein of the 20S U5 snRNP, absent from the mature tri-snRNP. Here we report a high-resolution cryogenic electron microscopy structure of the 20S U5 snRNP, shedding light on the mutually exclusive interfaces utilized during tri-snRNP assembly and the role of the CD2BP2 in facilita ...[more]

PMID: 38467877

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