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Cryo-EM structure of an early precursor of large ribosomal subunit reveals a half-assembled intermediate.

ABSTRACT: Assembly of eukaryotic ribosome is a complicated and dynamic process that involves a series of intermediates. It is unknown how the highly intertwined structure of 60S large ribosomal subunits is established. Here, we report the structure of an early nucleolar pre-60S ribosome determined by cryo-electron microscopy at 3.7 Å resolution, revealing a half-assembled subunit. Domains I, II and VI of 25S/5.8S rRNA pack tightly into a native-like substructure, but domains III, IV and V are not assembled. The structure contains 12 assembly factors and 19 ribosomal proteins, many of which are required for early processing of large subunit rRNA. The Brx1-Ebp2 complex would interfere with the assembly of domains IV and V. Rpf1, Mak16, Nsa1 and Rrp1 form a cluster that consolidates the joining of domains I and II. Our structure reveals a key intermediate on the path to establishing the global architecture of 60S subunits.

SUBMITTER: Zhou D

PROVIDER: S-EPMC6340896 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Cryo-EM structure of an early precursor of large ribosomal subunit reveals a half-assembled intermediate.

Zhou Dejian D Zhu Xing X Zheng Sanduo S Tan Dan D Dong Meng-Qiu MQ Ye Keqiong K

Protein & cell 20180319 2

Assembly of eukaryotic ribosome is a complicated and dynamic process that involves a series of intermediates. It is unknown how the highly intertwined structure of 60S large ribosomal subunits is established. Here, we report the structure of an early nucleolar pre-60S ribosome determined by cryo-electron microscopy at 3.7 Å resolution, revealing a half-assembled subunit. Domains I, II and VI of 25S/5.8S rRNA pack tightly into a native-like substructure, but domains III, IV and V are not assemble ...[more]

PMID: 29557065

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