TY - JOUR
T1 - Yeast Mitoribosome Large Subunit Assembly Proceeds by Hierarchical Incorporation of Protein Clusters and Modules on the Inner Membrane
AU - Zeng, Rui
AU - Smith, Erin
AU - Barrientos, Antoni
N1 - Funding Information:
We thank Dr. M. Deutscher and Dr. F. Fontanesi for scientific discussions and comments on the manuscript. We thank Dr. T. Fox, Dr. M. Ott, Dr. R. Stuart, Dr. J. Herrmann, Dr P. Rehling, and Dr. A. Tzagoloff for providing reagents. This research was supported by NIGMS -R35 grant GM118141 (to A.B.), MDA Grant MDA-381828 (to A.B.), and an American Heart Association predoctoral fellowship 16PRE29950001 (to R.Z.).
Funding Information:
We thank Dr. M. Deutscher and Dr. F. Fontanesi for scientific discussions and comments on the manuscript. We thank Dr. T. Fox, Dr. M. Ott, Dr. R. Stuart, Dr. J. Herrmann, Dr P. Rehling, and Dr. A. Tzagoloff for providing reagents. This research was supported by NIGMS-R35 grant GM118141 (to A.B.), MDA Grant MDA-381828 (to A.B.), and an American Heart Association predoctoral fellowship 16PRE29950001 (to R.Z.).
Publisher Copyright:
© 2018 Elsevier Inc.
PY - 2018/3/6
Y1 - 2018/3/6
N2 - Mitoribosomes are specialized for the synthesis of hydrophobic membrane proteins encoded by mtDNA, all essential for oxidative phosphorylation. Despite their linkage to human mitochondrial diseases and the recent cryoelectron microscopy reconstruction of yeast and mammalian mitoribosomes, how they are assembled remains obscure. Here, we dissected the yeast mitoribosome large subunit (mtLSU) assembly process by systematic genomic deletion of 44 mtLSU proteins (MRPs). Analysis of the strain collection unveiled 37 proteins essential for functional mtLSU assembly, three of which are critical for mtLSU 21S rRNA stability. Hierarchical cluster analysis of mtLSU subassemblies accumulated in mutant strains revealed co-operative assembly of protein sets forming structural clusters and preassembled modules. It also indicated crucial roles for mitochondrion-specific membrane-binding MRPs in anchoring newly transcribed 21S rRNA to the inner membrane, where assembly proceeds. Our results define the yeast mtLSU assembly landscape in vivo and provide a foundation for studies of mitoribosome assembly across evolution. Despite the biomedical relevance of the mitochondrial protein synthesis machinery, how mitoribosome biogenesis occurs remains largely unknown. By systematic deletion of 44 mitoribosome proteins in yeast, Zeng et al. describe a mitoribosome subunit assembly pathway, which occurs in contact with the mitochondrial inner membrane and involves hierarchical incorporation of protein clusters and modules.
AB - Mitoribosomes are specialized for the synthesis of hydrophobic membrane proteins encoded by mtDNA, all essential for oxidative phosphorylation. Despite their linkage to human mitochondrial diseases and the recent cryoelectron microscopy reconstruction of yeast and mammalian mitoribosomes, how they are assembled remains obscure. Here, we dissected the yeast mitoribosome large subunit (mtLSU) assembly process by systematic genomic deletion of 44 mtLSU proteins (MRPs). Analysis of the strain collection unveiled 37 proteins essential for functional mtLSU assembly, three of which are critical for mtLSU 21S rRNA stability. Hierarchical cluster analysis of mtLSU subassemblies accumulated in mutant strains revealed co-operative assembly of protein sets forming structural clusters and preassembled modules. It also indicated crucial roles for mitochondrion-specific membrane-binding MRPs in anchoring newly transcribed 21S rRNA to the inner membrane, where assembly proceeds. Our results define the yeast mtLSU assembly landscape in vivo and provide a foundation for studies of mitoribosome assembly across evolution. Despite the biomedical relevance of the mitochondrial protein synthesis machinery, how mitoribosome biogenesis occurs remains largely unknown. By systematic deletion of 44 mitoribosome proteins in yeast, Zeng et al. describe a mitoribosome subunit assembly pathway, which occurs in contact with the mitochondrial inner membrane and involves hierarchical incorporation of protein clusters and modules.
KW - 54S mitoribosome large subunit
KW - OXPHOS
KW - co-translational membrane insertion
KW - mitochondrial disease
KW - mitochondrial protein synthesis
KW - mitochondrial ribosome
KW - mitoribosome 21S rRNA
KW - mitoribosome assembly
KW - mitoribosome membrane anchoring
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U2 - 10.1016/j.cmet.2018.01.012
DO - 10.1016/j.cmet.2018.01.012
M3 - Article
C2 - 29514071
AN - SCOPUS:85042674766
VL - 27
SP - 645-656.e7
JO - Cell Metabolism
JF - Cell Metabolism
SN - 1550-4131
IS - 3
ER -