Mitochondrial ribosome bL34 mutants present diminished translation of cytochrome c oxidase subunits.

Autor: Guedes-Monteiro RF; Departamento de Microbiologia, Universidade de São Paulo, São Paulo, Brazil., Ferreira-Junior JR; Escola de Artes, Ciências e Humanidades, Universidade de São Paulo, São Paulo, Brazil., Bleicher L; Departamento de Bioquímica e Imunologia - Instituto de Ciências Biológicas - Universidade Federal de Minas Gerais, Belo Horizonte, Brazil., Nóbrega FG; Departamento de Microbiologia, Universidade de São Paulo, São Paulo, Brazil., Barrientos A; Department of Neurology, University of Miami Miller School of Medicine, Miami, Florida, USA., Barros MH; Departamento de Microbiologia, Universidade de São Paulo, São Paulo, Brazil.
Jazyk: angličtina
Zdroj: Cell biology international [Cell Biol Int] 2018 Jun; Vol. 42 (6), pp. 630-642. Date of Electronic Publication: 2017 Dec 07.
DOI: 10.1002/cbin.10913
Abstrakt: Saccharomyces cerevisiae mitoribosomes are specialized in the translation of a few number of highly hydrophobic membrane proteins, components of the oxidative phosphorylation system. Mitochondrial characteristics, such as the membrane system and its redox state driven mitoribosomes evolution through great diversion from their bacterial and cytosolic counterparts. Therefore, mitoribosome presents a considerable number of mitochondrial-specific proteins, as well as new protein extensions. In this work we characterize temperature sensitive mutants of the subunit bL34 present in the 54S large subunit. Although bL34 has bacterial homologs, in yeast it has a long 65 aminoacids mitochondrial N-terminal addressing sequence, here we demonstrate that it can be replaced by the mitochondrial addressing sequence of Neurospora crassa ATP9 gene. The bL34 temperature sensitive mutants present lowered translation of mitochondrial COX1 and COX3, which resulted in reduced cytochrome c oxidase activity and respiratory growth deficiency. The sedimentation properties of bL34 in sucrose gradients suggest that similarly to its bacterial homolog, bL34 is also a later participant in the process of mitoribosome biogenesis.
(© 2017 International Federation for Cell Biology.)
Databáze: MEDLINE
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