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Affinity grid-based cryo-EM of PKC binding to RACK1 on the ribosome.

ABSTRACT: Affinity grids (AG) are specialized EM grids that bind macromolecular complexes containing tagged proteins to obtain maximum occupancy for structural analysis through single-particle EM. In this study, utilizing AG, we show that His-tagged activated PKC ?II binds to the small ribosomal subunit (40S). We reconstructed a cryo-EM map which shows that PKC ?II interacts with RACK1, a seven-bladed ?-propeller protein present on the 40S and binds in two different regions close to blades 3 and 4 of RACK1. This study is a first step in understanding the molecular framework of PKC ?II/RACK1 interaction and its role in translation.

SUBMITTER: Sharma G

PROVIDER: S-EPMC3833090 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Affinity grid-based cryo-EM of PKC binding to RACK1 on the ribosome.

Sharma Gyanesh G Pallesen Jesper J Das Sanchaita S Grassucci Robert R Langlois Robert R Hampton Cheri M CM Kelly Deborah F DF des Georges Amedee A Frank Joachim J

Journal of structural biology 20121208 2

Affinity grids (AG) are specialized EM grids that bind macromolecular complexes containing tagged proteins to obtain maximum occupancy for structural analysis through single-particle EM. In this study, utilizing AG, we show that His-tagged activated PKC βII binds to the small ribosomal subunit (40S). We reconstructed a cryo-EM map which shows that PKC βII interacts with RACK1, a seven-bladed β-propeller protein present on the 40S and binds in two different regions close to blades 3 and 4 of RACK ...[more]

PMID: 23228487

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