Work

Direct visualization of translational GTPase factor pool formed around the archaeal ribosomal P-stalk by high-speed AFM

Year: 2020

Type: article

Abstract: The ribosomal stalk protein plays an essential role in the recruitment of translational GTPase factors EF1A and EF2 to the ribosome and their GTP hydrolysis for efficient translation elongation. However, due to the flexible nature of the ribosomal stalk, its structural dynamics and mechanism of action remain unclear. Here, we applied high-speed atomic force microscopy (HS-AFM) to directly visualize the action of the archaeal ribosomal stalk (P-stalk). HS-AFM movies clearly demonstrated the wobbling motion of the P-stalk on the large ribosomal subunit, where the stalk base adopted two conformational states, a predicted canonical state, and a newly identified flipped state. Intriguingly, archaeal aEF1A and aEF2 molecules spontaneously assembled around the ribosomal P-stalk up to the maximum number of available binding sites. These results provide the first visual evidence for the factor-pooling mechanism and reveal that the ribosomal P-stalk promotes translation elongation by increasing the local concentration of translational GTPase factors.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.2018975117

Authors: Hirotatsu Imai, Toshio Uchiumi, Noriyuki Kodera

Institutions: Kanazawa University, Niigata University

Language: English

Topic: RNA and protein synthesis mechanisms

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: hybrid

Funders: Kanazawa University, Japan Society for the Promotion of Science, Core Research for Evolutional Science and Technology