Structural basis of mitochondrial translation

eLife

Angelika Modelska¹  Alexey Amunts²  Shintaro Aibara³  Vivek Singh³ 

[1] Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden;Laboratory of Translational Genomics, Centre for Integrative Biology, University of Trento, Trento, Italy;Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden;

关键词: mitochondria;    translation;    ribosome;    RNA;    cryo-EM;    gene expression;   

DOI  :  10.7554/eLife.58362

来源: DOAJ

【 摘 要 】

Translation of mitochondrial messenger RNA (mt-mRNA) is performed by distinct mitoribosomes comprising at least 36 mitochondria-specific proteins. How these mitoribosomal proteins assist in the binding of mt-mRNA and to what extent they are involved in the translocation of transfer RNA (mt-tRNA) is unclear. To visualize the process of translation in human mitochondria, we report ~3.0 Å resolution structure of the human mitoribosome, including the L7/L12 stalk, and eight structures of its functional complexes with mt-mRNA, mt-tRNAs, recycling factor and additional trans factors. The study reveals a transacting protein module LRPPRC-SLIRP that delivers mt-mRNA to the mitoribosomal small subunit through a dedicated platform formed by the mitochondria-specific protein mS39. Mitoribosomal proteins of the large subunit mL40, mL48, and mL64 coordinate translocation of mt-tRNA. The comparison between those structures shows dynamic interactions between the mitoribosome and its ligands, suggesting a sequential mechanism of conformational changes.

【 授权许可】

Unknown